Rules for Building and Classing

Offshore Units

Part 6
Equipment and Machinery Certification

January 2025
RULES FOR BUILDING AND CLASSING

OFFSHORE UNITS
JANUARY 2025

PART 6
EQUIPMENT AND MACHINERY CERTIFICATION

American Bureau of Shipping

Incorporated by Act of Legislature of
the State of New York 1862

© 2025 American Bureau of Shipping. All rights reserved.

ABS Plaza
1701 City Plaza Drive
Spring, TX 77389 USA
 PART 6
Equipment and Machinery Certification

CONTENTS
CHAPTER 1 Material, Marine Equipment and Machinery Certification................ 1
Section 1 General.............................................................................. 9
Section 2 Hull Structure and Outfitting.............................................16
Section 3 Prime Movers...................................................................22
Section 4 Propulsion and Maneuvering Systems............................ 30
Section 5 Boilers, Pressure Vessels and Fired Equipment..............32
Section 6 Piping Systems ............................................................... 37
Section 7 Electrical Systems and Control Equipment......................45
Section 8 Fire and Safety - Equipment and Systems...................... 95
Section 9 Jacking and Associated Systems.................................... 99
Section 10 Mooring Systems and Equipment.................................. 116

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 ii

 PART 6
CHAPTER 1
Material, Marine Equipment and Machinery Certification

CONTENTS
SECTION 1 General..................................................................................................9
1 General........................................................................................... 9
1.1 Objective..........................................................................10
1.3 Marine and Propulsion Systems...................................... 10
3 Unit Certification........................................................................... 10
3.1 Basic Requirements.........................................................10
3.3 Specific Requirements.....................................................10
3.5 Angles of Inclination.........................................................11
3.7 Ambient Temperature.......................................................11
3.9 Skid Mounted Equipment or Machinery........................... 11
3.10 ABS Marking on Finished Components and Equipment..12
5 Design Review and Survey of Equipment and Machinery............12
5.1 Design Review.................................................................12
5.3 Survey..............................................................................12
7 Prototype Testing.......................................................................... 13
9 Type Approval Program................................................................ 13
9.1 Application and Limitations.............................................. 14
9.3 Structural Material............................................................14
9.5 Mass Produced Machinery.............................................. 14
9.7 Non-mass Produced Machinery...................................... 14
9.9 Design and Manufacturing Assessment (RQS and
PQA)................................................................................ 14
9.11 Type Examination and/or Testing, and Prototype
Testing............................................................................. 14
11 Manufacturer’s Guarantee............................................................14
11.1 Manufacturer’s Affidavit................................................... 15
13 Asbestos....................................................................................... 15

SECTION 2 Hull Structure and Outfitting.............................................................16

1 General ........................................................................................ 16
1.1 Objective..........................................................................16
3 Material for Hull Structure ............................................................ 17

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 1

 5 Material for Major Foundation Structures .................................... 17
7 Helideck Structure ....................................................................... 17
7.1 Material for Helideck Structure........................................ 17
7.3 Unit Certification of Helideck Structure............................ 18
9 Watertight Doors...........................................................................18
9.1 General............................................................................ 18
9.3 Sliding Watertight Doors.................................................. 18
9.5 Dogged Watertight Doors................................................ 19
11 Portable Modules .........................................................................19
11.1 General............................................................................ 19
11.3 Definition of Modules....................................................... 19
11.5 Container Box used as a Portable Industrial Module.......20

TABLE 1 Requirements for Portable Modules ....................................20

SECTION 3 Prime Movers..................................................................................... 22

1 General......................................................................................... 22
1.1 Objective..........................................................................22
3 Internal Combustion Engines........................................................23
3.1 Fuel Oil System............................................................... 23
3.3 Turbines for Generators...................................................24
3.5 Diesel Engines for Generators.........................................25
3.7 Prime Movers for Propulsion Generators........................ 26
3.9 References...................................................................... 27
5 Survey and Certification................................................................27

TABLE 1 Certification Details - Prime Movers.....................................28

FIGURE 1 Reference values for maximum possible sudden power

P (%) increases as a function of brake mean effective
pressure, Pme (kPa), at declared power (four-stroke
engines)............................................................................... 26

SECTION 4 Propulsion and Maneuvering Systems............................................30

1 General......................................................................................... 30
1.1 Objective..........................................................................30
3 Materials for Propulsion Equipment..............................................30
5 Survey and Certification................................................................30

TABLE 1 Certification Details - Propulsion and Maneuvering

Systems*.............................................................................. 31

SECTION 5 Boilers, Pressure Vessels and Fired Equipment............................ 32

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 1 General ........................................................................................ 32
1.1 Objective..........................................................................32
1.1 Application....................................................................... 32
1.3 Grouping of Boilers and Pressure Vessels...................... 33
3 Materials for Group I Boilers, Heaters, Pressure Vessels and
Heat Exchangers.......................................................................... 33
5 Survey and Certification................................................................33

TABLE 1 Certification Details - Boilers, Pressure Vessels and

Fired Equipment* ................................................................ 33
TABLE 2 Pressure Vessels and Heat Exchangers*............................ 34
TABLE 3 Grouping of Boilers, Pressure Vessels and Fired
Equipment*...........................................................................35

SECTION 6 Piping Systems ................................................................................. 37

1 General......................................................................................... 37
1.1 Objective..........................................................................37
3 Pipes.............................................................................................38
3.1 Manufacturer’s Certification............................................. 38
3.3 Identification.....................................................................38
3.5 Plastic Piping................................................................... 38
5 Piping Components other than Pipes........................................... 39
5.1 Pipe Fittings and Valves.................................................. 39
5.3 Flexible Hoses................................................................. 40
5.5 Vent Heads and Pressure/Vacuum Valves...................... 40
5.7 Gauges, Detectors, and Transmitters.............................. 40
5.9 Fluid Power Cylinders......................................................40
5.11 Pumps..............................................................................40
5.13 Non-standard Components..............................................40
7 Survey and Certification................................................................40
7.1 Survey and Certification of Pipes.....................................40
7.3 Survey and Certification of Piping Components other
than Pipes........................................................................41

TABLE 1 Certification Details - Piping System Components ..............43

TABLE 2 Piping Classes and Certification ......................................... 44

SECTION 7 Electrical Systems and Control Equipment.................................... 45

1 Objective.......................................................................................45
1.1 Goals............................................................................... 45
1.2 Functional Requirements.................................................46
1.3 Compliance......................................................................48
2 General......................................................................................... 48
2.1 Insulation Material............................................................48

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 2.3 Accessibility..................................................................... 49
2.5 Handrails..........................................................................49
3 Plans and Data to be Submitted .................................................. 49
3.1 Rotating Machines of 100 kW and Over.......................... 49
3.3 Switchboards, Distribution Boards, Controllers, etc.........50
3.5 Semiconductor Converters for Adjustable Speed
Motor Drives.................................................................... 50
5 Rotating Machines........................................................................ 50
5.1 General............................................................................ 50
5.3 Insulation Resistance Measurement................................51
5.5 Overload and Overcurrent Capability.............................. 51
5.7 Dielectric Strength of Insulation....................................... 52
5.9 Temperature Ratings....................................................... 52
5.11 Construction and Assembly............................................. 53
5.13 Lubrication....................................................................... 54
5.15 Operating and Overspeed Governors for Generator
Prime Movers...................................................................54
5.17 Alternating-Current (AC) Generators............................... 54
5.19 Direct-Current (DC) Generators.......................................56
5.21 AC Generating Sets.........................................................57
7 Accumulator Batteries...................................................................57
7.1 General............................................................................ 57
7.3 Construction and Assembly............................................. 58
9 Switchboards, Distribution Boards, Controllers, etc......................58
9.1 General............................................................................ 58
9.3 Insulation Resistance Measurement................................59
9.5 Dielectric Strength of Insulation....................................... 59
9.7 Construction and Assembly............................................. 60
9.9 Bus Bars, Wiring and Contacts........................................60
9.11 Control and Protective Devices....................................... 62
9.13 Switchboards................................................................... 63
9.15 Motor Controllers and Control Centers............................ 64
9.17 Battery Systems and Uninterruptible Power Systems
(UPS)............................................................................... 64
11 Transformers.................................................................................65
11.1 General............................................................................ 65
11.3 Temperature Rise............................................................ 66
11.5 Construction and Assembly............................................. 66
12 Semiconductor Converters for Adjustable Speed Motor Drives .. 67
12.1 Application....................................................................... 67
12.3 Standards of Compliance................................................ 67
12.5 Design, Construction and Assembly Requirements........ 67
12.7 Inspection and Testing..................................................... 71
12.9 Integration Requirements................................................ 74

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 13 Other Electric and Electronics Devices.........................................75
13.1 Circuit Breakers............................................................... 75
13.3 Fuses............................................................................... 75
13.5 Semiconductor Converters.............................................. 76
13.7 Cable Junction Boxes...................................................... 76
15 High Voltage Systems...................................................................76
15.1 General............................................................................ 76
15.3 Machinery and Equipment............................................... 76
17 Electric Propulsion System........................................................... 78
17.1 General............................................................................ 78
17.3 Machinery and Equipment............................................... 79
19 Survey and Certification................................................................81
19.1 Generators and Motors ≥ 100 kW (135 hp) intended
for Essential Services...................................................... 81
19.3 Propulsion Generators and Motors..................................82
19.5 Switchboards................................................................... 82
19.7 Motor Controllers and Control Centers intended for
Essential Services ≥ 100 kW (135 hp).............................82
19.9 Battery Charging Units ≥ 25 kW, UPS units ≥ 50 kVA,
and Associated Distribution Boards, for Essential,
Emergency or Transitional Source of Power................... 82
19.11 Power Transformers ≥ 100 kVA and Converters for
High Voltage Systems over 1 kV, for Essential or
Emergency Source of Power........................................... 83
19.13 Semiconductor Converters for Propulsion (only for
Self-Propelled Units)........................................................83
19.15 Propulsion Cables other than Internal Wiring in
Control Gears and Switchboards (only for Self-
Propelled Units)............................................................... 84
19.17 Controls for Electric Propulsion Equipment (only for
Self-Propelled Units)........................................................84
19.19 High Voltage (HV) Systems - Rotating Machinery........... 84
19.21 High Voltage (HV) Systems - Switchgear and
Control-Gear Assemblies.................................................84
19.23 High Voltage (HV) Systems -Transformers......................85

TABLE 1 Certification Details – Electrical Systems and Control

Equipment............................................................................ 85
TABLE 2 Factory Testing Schedule for Generators and Motors ≥
100 kW (135 hp) (8, 9) [See 6-1-7/19.1 and 6-1-7/19.3] ........ 87
TABLE 3 Dielectric Strength Test for Rotating Machines [See
6-1-7/5.7] .............................................................................88
TABLE 4 Limits of Temperature Rise for Air-Cooled Rotating
Machines [See 6-1-7/5.9.1] ................................................. 89
TABLE 5 Nameplates ......................................................................... 91

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 5

 TABLE 6 Factory Testing Schedule for Switchboards, Chargers,
Motor Control Centers, and Controllers [See 6-1-7/19.5,
6-1-7/19.7 and 6-1-7/19.9] .................................................. 91
TABLE 7 Clearance and Creepage Distance for Switchboards,
Distribution Boards, Chargers, Motor Control Centers
and Controllers (1) [See 6-1-7/9.9.6] .................................... 92
TABLE 8 Equipment and Instrumentation for Switchboard [See
6-1-7/9.13.4] ........................................................................92
TABLE 9 Temperature Rise for Transformers* [See 6-1-7/11.3] ........ 94

SECTION 8 Fire and Safety - Equipment and Systems...................................... 95

1 Objective.......................................................................................95
1.1 Goals............................................................................... 95
1.2 Functional Requirements.................................................95
1.3 Compliance......................................................................96
2 General......................................................................................... 96
3 Fire Doors..................................................................................... 96
5 Fire-Rated Windows..................................................................... 96
7 Gas-Tight Doors............................................................................96
9 Fire and Gas Detection Systems.................................................. 97
11 Fire Pumps................................................................................... 97
13 Survey and Certification................................................................97

TABLE 1 Certification Details - Safety Equipment and Systems ........97

SECTION 9 Jacking and Associated Systems.................................................... 99

1 Objective.......................................................................................99
1.1 Goals............................................................................... 99
1.2 Functional Requirements...............................................100
1.3 Compliance....................................................................100
2 General....................................................................................... 100
3 Definitions................................................................................... 101
3.1 Jacking System..............................................................101
3.3 Holding Mechanism....................................................... 101
3.5 Rack and Pinion Jacking System.................................. 101
3.7 Yoke and Pin Jacking System........................................101
3.9 Fixation System............................................................. 101
3.11 Specified Service Temperature......................................101
3.13 Jacking Unit Rated Capacity..........................................101
3.15 Lifting Capacity per Leg................................................. 102
3.17 System Integrator.......................................................... 102
5 Plans and Data to be Submitted ................................................ 102
7 Failure Modes and Effects Analysis (FMEA) ............................. 103
9 Material ...................................................................................... 103

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 9.1 Toughness..................................................................... 104
11 Strength Analysis .......................................................................105
11.1 Conditions to be Analyzed............................................. 105
11.3 Strength......................................................................... 106
11.5 Buckling......................................................................... 107
11.7 Fatigue...........................................................................107
11.9 Alignment.......................................................................107
13 Mechanical Components............................................................ 108
13.1 Bearings.........................................................................108
13.3 Brakes............................................................................108
13.5 Flexible Shock Pads...................................................... 108
15 Electrical Power System............................................................. 108
15.1 Electric Motor Drive....................................................... 108
17 Hydraulic System .......................................................................109
17.1 Hydraulic Motor Drive.................................................... 109
19 Control, Monitoring and Alarm System ...................................... 109
19.1 Programmable Electronic System (PES)....................... 110
21 Low Temperature Operation....................................................... 110
23 Jacking Systems of Novel Design...............................................110
25 Survey and Certification.............................................................. 111
25.1 Inspection and Material Testing......................................111
25.3 Prototype Test................................................................ 112
25.5 Replacement Jacking Equipment for Units in
Operation....................................................................... 112

TABLE 1 Charpy V-Notch (CVN) Impact Requirements for Steel

Materials ............................................................................105
TABLE 2 Certification Details – Jacking and Associated
Systems(1,3)......................................................................... 113

SECTION 10 Mooring Systems and Equipment.................................................. 116

1 Objective..................................................................................... 116
1.1 Goal and Functional Requirements............................... 116
1.2 Compliance.................................................................... 116
2 General ...................................................................................... 116
3 Temporary Mooring Equipment...................................................116
3.1 Inspection and Material Testing..................................... 117
3.3 Prototype Testing of Anchor Windlass........................... 117
5 Survey and Certification of Position Mooring Equipment Ⓜ or
M-PL........................................................................................... 117
7 Survey and Certification of Position Mooring Systems Ⓟ or
P-PL............................................................................................ 117
9 Survey and Certification of Position Mooring Systems TAM,
TAM-R, TAM (Manual), TAM-PL or TAM-PL(Manual)................. 117

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 TABLE 1 Certification Details - Temporary Mooring Equipment
with Ⓔ Symbol .................................................................. 118
TABLE 2 Certification Details - Temporary Mooring Equipment
without Ⓔ Symbol.............................................................. 118
TABLE 3 Certification Details – Position Mooring Equipment for
Ⓜ or M-PL Symbol ............................................................ 119
TABLE 4 Certification Details – Position Mooring Equipment for
Ⓟ or P-PL Symbol .............................................................119
TABLE 5 Certification Details – Position Mooring System for
TAM, TAM-R, TAM (Manual), TAM-PL or TAM-
PL(Manual) Symbol ...........................................................120

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 8

 PART 6
CHAPTER 1
Material, Marine Equipment and Machinery Certification

SECTION 1
General

1 General
This Section contains general requirements to certify material for:

● hull structure,
● equipment and machinery for hull outfitting,
● equipment and machinery for marine systems, and
● propulsion system, if it is a self-propelled unit

at manufacturer’s plant (unit certification), prior to onboard installation and testing in a offshore unit at
builder’s yard. The subsequent Sections contain requirements to certify individual product types.

This Chapter does not cover requirements for the optional ABS Class Notations such as ACC or AMCC or
ACCU or AMCCU for automation systems, CDS for systems or DPS for dynamic positioning systems.

AUTONOMOUS and REMOTE-CON notations are mandatory for units with permanently installed
autonomous or remote-controlled functions and signify compliance with ABS Requirements for
Autonomous and Remote Control Functions.

Commentary:

Autonomous Functions are functions where machines perform each of the four steps in the operational decision loop (i.e.,
Monitoring, Analysis, Decision and Action) without the need for human intervention to perform tasks and achieve the
system mission.

End of Commentary

For the construction of the offshore unit, ABS Rules and Guides effective at the time the contract is signed
between the owner and builder are to be used for the certification of manufacturer’s products.

In addition to the requirements contained in this Chapter, the design requirements given in Parts 3, 4 and 5
and the survey and testing requirements during fabrication, onboard installation, testing after installation,
and final trial given in Sections 7A-1-1 through 7A-1-8, or Chapters 1 and 2 of Part 7B as applicable, are
to be considered during the certification of the manufacturer’s product.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 1 General 6-1-1

1.1 Objective
1.1.1 Goal and Functional Requirements
The goals and functional requirements in the cross-referenced Rules/Regulations are to be met.

1.1.2 Compliance
A unit is considered to comply with the Goals and Functional Requirements when the applicable
prescriptive requirements are complied with or when an alternative arrangement has been
approved. Refer to Part 1D, Chapter 2.

1.3 Marine and Propulsion Systems

Boilers, pressure vessels, heat exchangers, internal combustion engines, turbines, propulsion equipment,
steering gear and other applicable equipment are to be in accordance with the requirements of the Marine
Vessel Rules, except as modified herein.

3 Unit Certification

3.1 Basic Requirements

The Rules define, to varying degrees, the extent of evaluation required for products to be manufactured
based on the level of criticality of each of those items. There are two basic evaluation constituents:

i) Design review; prototype testing

ii) Survey during construction and testing at the plant of manufacture

Where design review is required by the Rules, a letter will be issued by ABS upon satisfactory review of
the plans to evidence the acceptance of the design. In addition to, or independent of, design review, ABS
may require survey and testing of forgings, castings and component parts at the various manufacturers’
plants, as well as survey and testing of the finished product. A report is issued upon satisfactory
completion of each survey to evidence acceptance of the product. Design review, survey and the issuance
of reports constitute the unit certification of a product.

Where the product is accepted in accordance with Product Quality Assurance (PQA) assessment of ABS
Type Approval Program, survey and testing of the product in presence of a Surveyor is not required.
However, product’s unit certification is issued by the ABS office having jurisdiction over the manufacturer.
For further details, see 1B-1-A2/5.7 of these Rules.

Based on the intended service and application, some products do not require certification because they are
not directly related to the scope of classification or because normal practices for their construction within
the industry are considered adequate. Such products are acceptable based on the manufacturers’
documentation on design and quality, which guarantees product’s acceptance for classification provided it
is satisfactorily installed and tested onboard the unit.

Surveys during installation onboard the vessel and at trials are required for all items of machinery. This is
not considered a part of the product certification process. For onboard installation and trials, refer to Part
7A or 7B of these Rules as applicable.

3.3 Specific Requirements

Sections 2 through 10 of this Chapter describe specific certification requirements for material, marine
equipment and machinery used in following areas:

i) Hull Structure and Outfitting (Section 6-1-2)

ii) Prime Movers (Section 6-1-3)
iii) Propulsion and Maneuvering Systems (Section 6-1-4)
iv) Boilers, Pressure Vessels and Fired Equipment (Section 6-1-5)

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 1 General 6-1-1

v) Piping Systems (Section 6-1-6)

vi) Electrical Systems and Control Equipment (Section 6-1-7)
vii) Fire and Safety – Equipment and Systems (Section 6-1-8)
viii) Jacking and Associated System – Self-Elevating Units (Section 6-1-9)
ix) Mooring Systems and Equipments (Section 6-1-10)

3.5 Angles of Inclination

All equipment, machinery and their components intended for essential services, as defined in 4-1-1/3.5, are
to be designed to operate under the inclinations as indicated for each of the conditions listed in 4-1-1/
TABLE 1.

For emergency generator, its prime mover and any emergency accumulator battery, see also 4-3-2/5.5.

The equipment manufacturer is to submit:

● Test reports showing operation under maximum angles of inclination, or

● Calculations or simulation, or
● Evidence of satisfactory service experience
Note:

The above requirements do not apply to jacking systems of self-elevating units. Jacking systems are to be operable at
maximum angle of inclination stated in the manufacturer’s specification.

3.7 Ambient Temperature

For units of unrestricted service, all equipment and machinery, and their components intended for essential
services, as defined in 4-1-1/3.5, are to be designed to operate under the ambient temperatures as indicated
for each of the conditions listed in 4-1-1/ TABLE 2.

For units of restricted or special service, the ambient temperature appropriate to the special nature is to be
considered.

3.9 Skid Mounted Equipment or Machinery

Where skid mounted equipment or machinery is required to be design reviewed and surveyed in
accordance with subsequent Sections 6-1-3, the skid is also required to be design reviewed and surveyed at
manufacturer’s facility if the skid mounted unit has either of the following:

● Center of gravity height is more than 1.5 m (5 ft) in dry condition, or

● Maximum operating weight is in excess of 10 MT (metric tons) or 22.05 Kips.
3.9.1 Design Review
Design of the skid mounted equipment and machinery, together with structural design
calculations, is to be submitted to ABS for review.

Note:

Containers and associated lifting sets used solely for shipping or transferring equipment to the unit are not subject
to the requirement of this Section. The ABS Guide for the Certification of Offshore Containers may be applied for
these items outside the scope of these Rules.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 1 General 6-1-1

3.9.2 Survey
Surveyor’s attendance is required to verify that the skid mounted equipment/machinery is in
compliance with ABS reviewed design and structural design calculations, and to at least carry out
the following:

i) Verify Material Test Report (MTR) of skid material.

ii) Visual examination of final weldments of skid structure.
iii) Witness load testing of the skid structure lifting lugs or pad-eyes. Load test of the skid is
to be carried out at maximum static load the lifting lugs or pad eyes during the
transportation or installation of the equipment/machinery onboard the unit.
iv) Witness surface Nondestructive Testing (NDT) of skid structure weldments of the lifting
lugs/pad eyes, after completion of the skid structure load test. Magnetic Particle
Inspection (MPI) is recommended for NDT.
v) Verify proper alignment of assembled equipment/machinery components.
vi) Verify proper mechanical and electrical connections.
vii) Witness leak/pressure test, as applicable.
viii) Witness Factory Acceptance Test (FAT) of the equipment/machinery on skid.

3.10 ABS Marking on Finished Components and Equipment

All finished component/equipment issued with unit certificates are to be permanently marked at an
accessible location for identification and traceability. The identification is to include but is not limited to
the model number or part number, serial number and other data that may be necessary to comply with any
other ABS Rule requirements.

At the request of the manufacturer, an ABS Marking may be applied. The marking is to include the ABS
mark (✠) and a unique identification number generated by ABS.

An example of ABS marking: ✠ 123456.

Markings are to be permanently marked (i.e. steel-die-stamped, laser etched, etc.) at an accessible location
by the manufacturer on each finished component or equipment.

ABS Certificates for the components and equipment are to be provided to the responsible party (e.g. owner
or shipyard) and Surveyor at installation.

5 Design Review and Survey of Equipment and Machinery

5.1 Design Review

Plans and data required to be submitted for certification of specific equipment and machinery are described
under Section 6-1-3.

5.3 Survey
Certain equipment and machinery and/or associated components require Surveyor’s attendance at the
manufacturer’s plant during fabrication and testing of the respective product. Satisfactorily completed
survey of the product is to be reported upon, only if the required ABS design review of the product was
completed without any outstanding engineering comment.

During fabrication of equipment, the attending Surveyor is to have access to manufacturers’ facilities and
assembly sites to witness fabrication and/or testing, as required by these Rules. The manufacturer is to
contact the attending Surveyor to make necessary arrangements. If the attending Surveyor finds reason to

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 1 General 6-1-1

recommend repairs or additional surveys, notice is immediately given to the manufacturer’s representative
so that appropriate action may be taken.

Each manufacturer is required to have an effective quality system which is to be verified by the attending
Surveyor. Unless the manufacturer holds an effective ABS Product Quality Assurance (PQA) Certificate,
Surveyor’s attendance is required, typically to.

i) Confirm that the facilities to manufacture, fabricate or repair mechanical or electrical marine
components have and maintain an effective Quality Control Program (QCP) effectively covering
design, procurement, manufacturing and testing, as applicable, and meeting the requirements of a
recognized standard applied to their product.
ii) Qualify or verify welder’s qualifications to the extent deemed necessary by the attending
Surveyor.
iii) Qualify or verify welding procedure specifications and corresponding weld procedure
qualification records to the extent deemed necessary by the attending Surveyor.
iv) Verify material certificates/documentation.
v) Survey fit-up prior to major weldments.
vi) Survey final weldments.
vii) Witness, as far as deemed necessary, Non-Destructive Testing (NDT) of welds and to review
records of NDT.
viii) Verify dimensions are the same as shown on approved drawings.
ix) Check dimensional tolerances and alignment of mating surfaces.
x) Witness prototype testing of jacking gear system subject to such testing in accordance with these
Rules.
xi) Witness pressure and/or proof-load testing of equipment components and as a unit, as applicable
and as called for in the fabrication procedures.
xii) Witness final testing and functional testing of subassemblies and completed units, as called for in
the fabrication procedures.
xiii) Carry out other surveys as agreed upon during prefabrication meeting, including the Factory
Acceptance Test (FAT).

Surveys required for certification of specific equipment are described under subsequent Section 6-1-3.

7 Prototype Testing
Where prototype testing is required by these Rules, Surveyor is to witness the prototype testing at the plant
of manufacture, and report upon the test results. Results of the prototype testing endorsed by the Surveyor
are to be submitted to respective Engineering office to supplement the completed design review or where
type testing was done in lieu of design review. Subsequent testing of the product that has been already
prototype tested may be carried out by the manufacturer and test results accepted based upon previously
completed prototype testing of the product.

Subsequent Section 6-1-3 describes products that may be required to be subjected to prototype testing.

9 Type Approval Program

The process of the ABS Type Approval program is explained in 1B-1-4/9.7 and Appendix 1B-1-A2 of the
ABS Rules for Conditions of Classification - Offshore Units (Part 1B).

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 1 General 6-1-1

9.1 Application and Limitations

For reference purposes, applicable Tables in subsequent Sections contain examples of the limitations of the
Program for marine equipment and machinery. Products that are not listed in the Tables may be considered
for inclusion in the Type Approval Program on a case-by-case basis. The manufacturer is to contact the
nearest ABS office for advice.

9.3 Structural Material

Structural material, including certain piping material used for structural support purposes (Section 6-1-2),
is required to be certified in accordance with these Rules by a Surveyor attending the ABS approved steel
mill. Type Approval Program is not applicable to certification of structural material.

9.5 Mass Produced Machinery

Manufacturers of mass-produced machinery, who operate a quality assurance system in the manufacturing
facilities, may apply to ABS for a quality assurance assessment described in 1B-1-A2/5.5 (PQA).

Upon satisfactory assessment under1B-1-A2/5.5 (PQA), mass-produced machinery produced in those

facilities do not require a Surveyor's attendance at the tests and inspections. Such tests and inspections are
to be carried out by the manufacturer whose quality control documents are acceptable. Certification of
mass-produced machinery is based on verification of approval of the design and on continued effectiveness
of the quality assurance system. See 1B-1-A2/5.7.1(a).

9.7 Non-mass Produced Machinery

Non-mass produced critical machinery, such as propulsion boilers, slow speed diesel engines, turbines,
steering gears, and similar critical items are to be individually unit certified in accordance with the
procedure described in 6-1-1/3.1. However, consideration is given to granting Type Approval to such
machinery in the category of Recognized Quality System (RQS).

The category of Product Quality Assurance (PQA) is not normally available for all products, and such
limitations are indicated in the respective Tables of subsequent Sections. In each instance where Type
Approval is granted, in addition to quality assurance and quality control assessment of the manufacturing
facilities, ABS requires some degree of product specific survey during manufacture.

9.9 Design and Manufacturing Assessment (RQS and PQA)

The Tables in subsequent Sections contain the requirements for Type Approval of the listed components
and equipment with regard to Product Design Assessment (Design Review and Prototype Testing) and
Manufacturing Assessment (PQA option only). Manufacturing Assessment in the category of Recognized
Quality System (RQS) may be carried out on any product and therefore, are not shown on the Tables.

9.11 Type Examination and/or Testing, and Prototype Testing

Any product requested to be Type Approved is to be subjected to type examination and testing in the
presence of the Surveyor attending the manufacturer’s plant for initial assessment. Therefore, the type
exam or type testing of the initial product required by the Type Approval Program, as referenced in
1B-1-4/9.7 and Appendix 1B-1-A2, are not indicated under the applicable Tables contained in subsequent
Sections.

Where prototype test is required as indicated in the applicable Tables of this Chapter, the type examination
and/or testing of the initial product for Type Approval may be waived, provided the design or fabrication
process of the product remain unchanged since it was prototype tested.

11 Manufacturer’s Guarantee
All products manufactured for installation onboard a classed unit are expected to operate in a safe and
appropriate manner, and guaranteed by the manufacturer to do so, as long as the recommended
maintenance procedure of the product is adhered to by the owner/operator.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 1 General 6-1-1

11.1 Manufacturer’s Affidavit

Where a manufactured product does not require Surveyor attendance for unit certification, Surveyor’s
attendance is not requested by the client, or the product is not certified under the ABS Type Approval
Program, the manufacturer’s guarantee for product’s compliance with a recognized standard is acceptable
to ABS, provided the product as installed onboard satisfy the classification requirements of the unit. Where
requested by ABS, the manufacturer’s affidavit is to be submitted.

13 Asbestos
Installation of material, containing asbestos is prohibited.

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 PART 6
CHAPTER 1
Material, Marine Equipment and Machinery Certification

SECTION 2
Hull Structure and Outfitting

1 General
Materials used for hull construction and hull outfitting are covered in more detail in other relevant sections
of the Rules identified below.

Where material other than steel is used, material suitability and test results per the International Code for
Application of Fire Test Procedures (FTP Code) is to be acceptable to ABS.

1.1 Objective
1.1.1 Goal
The hull structure and outfitting covered in this section shall be designed, constructed, operated,
and maintained to:

Goal No. Goal

STAB 1 have adequate watertight integrity and restoring energy to prevent capsize in an intact
condition.

STRU 1 in the intact condition, have sufficient structural strength to withstand the environmental
conditions, loading conditions, and operational loads anticipated during the design life.

STRU 3 provide protection to persons onboard, the environment and required safety services.

Materials are to be suitable for the intended application in accordance with the following goals
and support the Tier 1 goals as listed above.

Goal No. Goal

MAT 1 The selected materials’ physical, mechanical and chemical properties are to meet the design
requirements appropriate for the application, operating conditions and environment.

The goals in the cross-referenced Rules/Regulations are also to be met.

1.1.2 Functional Requirements

In order to achieve the above stated goals, the design, construction, installation and maintenance
of hull structure and outfitting are to be in accordance with the following functional requirements:

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 2 Hull Structure and Outfitting 6-1-2

Functional Functional Requirements

Requirement No.
Stability (STAB)

STAB-FR1 Watertight doors are to have sufficient strength to withstand the water pressure they may be
subjected to.

STAB-FR2 (MAT) Avoid using liner materials that are readily rendered ineffective by heat or decay easily.

Structure (STRU)

STRU-FR1 Portable modules are to be securely fixed to the ship's structure to prevent movement or
detachment during extreme weather or other adverse conditions which can cause hazard to
the unit or the personnel onboard the unit.

The functional requirements in the cross-referenced Rules /Regulations are also to be met.

1.1.3 Compliance
A unit is considered to comply with the goals and functional requirements when the applicable
prescriptive requirements are complied with or when an alternative arrangement has been
approved. Refer to Part 1D, Chapter 2.

3 Material for Hull Structure

Materials used for hull construction and hull outfitting are to be in accordance with Section
3A-1-4, and Part 3A, Chapter 2 or Part 3B, Chapter 2 or Part 3C, as applicable.

5 Material for Major Foundation Structures

Major foundations include but not limited to the foundations for the following equipment or machinery:

● Pedestal cranes for loading/unloading of equipment and personnel.

● Anchoring or mooring system winches.
● Fairleads.

Material used for major foundation structures are to be in accordance with ABS approved drawings. In lieu
of unit certification, manufacturer’s Material Test Report (MTR) for materials used for major foundations
and tested in accordance with the ABS Rules for Materials and Welding (Part 2), or Section 3A-1-4, as
applicable, may be accepted by the Surveyor. The Material Test Report (MTR) of each member is to be
available to the Surveyor before being installed onboard.

All major foundation structures affect classification of a unit and are required to be design reviewed in
accordance with Sections (a) 3A-2-2, 3A-2-3, 3A-2-4, and 3A-2-5, (b) 3B-2-2, 3B-2-3, 3B-2-4, and
9-10-1, or (c) 3C-2-2, as applicable, and surveyed during fabrication and installation.

7 Helideck Structure
Certification of helideck structure is required and the helideck structure is to be designed in accordance
with 3A-2-2/3, 3B-2-3/2.5, 3C-2-2/2.5, 3C-3-3/2.7, or 3C-4-3/2.7, as applicable, and certified in
accordance with this Chapter.

7.1 Material for Helideck Structure

The helideck structure deck plating and its main support structural members fabricated out of steel or other
acceptable material need not be produced by an ABS approved mill and certified by an ABS Surveyor.
However, the selection of such structural materials is to be in accordance with Section 3A-1-4, and the

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 2 Hull Structure and Outfitting 6-1-2

Material Test Report (MTR) of each member is to be available to the Surveyor before being installed
onboard.

7.3 Unit Certification of Helideck Structure

If the helideck structure is fabricated within the builder’s yard where the unit is being built, design and
fabrication of the helideck structure are to be in accordance with 3A-2-2/3, 3B-2-3/2.5, 3C-2-2/2.5,
3C-3-3/2.7, or 3C-4-3/2.7, as applicable, and built in presence of and to the satisfaction of the Surveyor. In
such a case, the helideck is considered as part of the rig's construction.

If the helideck structure is fabricated away from the builder’s yard where the unit is being built, design and
fabrication of the helideck structure is to be in accordance with 3A-2-2/3, 3B-2-3/2.5, 3C-2-2/2.5,
3C-3-3/2.7, or 3C-4-3/2.7, as applicable, and built in presence of and to the satisfaction of the Surveyor. In
such case, the helideck is to be treated as a product to be unit certified.

9 Watertight Doors
Certification of watertight doors are to be designed, fabricated and tested in accordance with this Section.

9.1 General
Watertight doors are to be designed to withstand water pressure to a head up to the bulkhead deck or
freeboard deck respectively. A prototype pressure test is to be conducted for each type and size of door to
be installed on the unit at a test pressure corresponding to at least the head required for the intended
location. The prototype test is to be carried out at the manufacturer’s plant. The installation method and
procedure for fitting the door on board is to correspond to that of the prototype test. Large doors or hatches
of a design and size that make pressure testing impracticable may be exempted from the prototype pressure
test, provided that it is demonstrated by calculations that the doors or hatches maintain watertightness at
the design pressure.

Watertight doors are to be of ample strength for the water pressure to which they may be subjected.
Doorframes are to be carefully fitted to the bulkheads; where liners are required, the material is to be not
readily injured by heat or by deterioration.

Reference is also made to 3A-3-2/5.3, 3C-2-3/2.7, 3C-3-2/3.3, or 3C-4-2/3.3 with regard to watertight
integrity of the unit.

9.3 Sliding Watertight Doors

Sliding watertight doors are to be tested for operation at the manufacturer’s plant. Watertightness of doors
which become immersed by an equilibrium or intermediate waterplane at any stage of assumed flooding is
to be confirmed by prototype hydrostatic testing at the manufacturer’s plant. The head of water used for the
test is to correspond at least to the head measured from the lower edge of the door opening at the location
in which the door is to be fitted in the vessel, to:

i) The bulkhead deck or freeboard deck, as applicable, or

ii) The most unfavorable damage waterplane, if that is greater

Fabrication, hydrostatic testing, and satisfactory operational testing are to be carried out at the
manufacturer’s plant in the presence of the Surveyor as indicated in 6-1-2/9.1 and a Survey report is to be
issued.

Doors above freeboard or bulkhead deck, which are not immersed by an equilibrium or intermediate
waterplane but become intermittently immersed at angles of heel in the required range of positive stability
beyond the equilibrium position, are to be hose tested after installation onboard.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 2 Hull Structure and Outfitting 6-1-2

9.5 Dogged Watertight Doors

Non-sliding dogged watertight doors are to be certified. Dogged watertight doors are to be manufactured in
accordance with ABS approved drawings and subjected to type testing.

Dogged watertight doors are to be subjected to a hydrostatic test as indicated in 6-1-2/9.1 at the
manufacturer’s plant.

Fabrication, hydrostatic testing and satisfactory operational testing of the doors during the prototype
testing are to be witnessed by a Surveyor and reported upon. Dogged doors that have satisfactorily
completed its type-testing may then be certified without unit certification, preferably under the ABS Type
Approval Program.

11 Portable Modules
Certification of portable modules is required as indicated in 6-1-2/TABLE 1 and they are to be designed
and fabricated in accordance with this Section.

11.1 General
Portable modules are used to support various functions onboard the unit. Portable modules are expected to
be used throughout the duration needed in support of unit operations, as scheduled by the Owner/Operator.

Acceptance criteria for various types of portable modules located in special areas or stacked higher than
two units are shown in 6-1-2/TABLE 1.

11.3 Definition of Modules

Types of portable modules referenced in 6-1-2/TABLE 1 are defined below.

11.3.1 Accommodation Modules

Modules used for services defined as “accommodations” according to the ABS Requirements for
Portable Accommodation Modules. These portable modules are used as:

i) Sleeping Quarters
ii) Hospital
iii) Galley
iv) Dining Room
v) Office
vi) Recreation Room, Gym, TV Room, Cinema, Lounge, Library, Prayer Room
vii) Training Room
11.3.2 Certified Modules
Modules that require additional design review in accordance with these Rules, the Marine Vessel
Rules, or the IMO MODU Code/SOLAS, applicable to the vessel. These portable buildings are
used as:

i) Control Stations (as defined in these Rules and the IMO MODU Code)
ii) Space for Essential Services (as defined in these Rules and the IMO MODU Code)
iii) Machinery Space Category A (as defined in these Rules and the IMO MODU Code)
iv) High Risk Service Spaces (such as spaces used for mud logging, well test labs, storage of
flammable liquids, battery (>2 kW) rooms)
v) Storage of equipment for classed drilling systems, if applicable
vi) Other services covered under the IMO MODU Code

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 2 Hull Structure and Outfitting 6-1-2

11.3.3 Industrial Modules

Modules that do not require additional design review but do require an onboard installation
survey. These portable modules are used as:

i) Space for Non-Essential Services such as MCC, switchgears, dedicated drilling

equipment, if applicable
ii) Laundry
iii) Low Risk Service Spaces such as spaces used as workshops or storage of batteries <2 kW
iv) Communication equipment buildings
v) ROV vans
vi) Mud logging buildings without returns
11.3.4 Exempt Modules
Modules that do not require design review or an onboard survey. These portable modules are:

i) Unmodified container boxes

ii) Container boxes with modified doors only (without any piping or electrical equipment)
iii) Wireline units
iv) Pantries (dry storage only)
v) Refrigeration spaces

11.5 Container Box used as a Portable Industrial Module

Where a container box is used as a portable module, the container is to be confirmed as being certified to a
recognized standard, and is to be properly secured to the deck.

11.5.1 Means of Securing Container Boxes

Ultimate responsibility regarding efficiency of securing container boxes to the unit’s structure
reside with the Owner.

Container boxes are at all times to be sufficiently secured to deck to prevent any safety hazard to
the unit or the personnel onboard the unit.

Means of securing a single container to deck other than welding is acceptable provided the
attending Surveyor is satisfied with the arrangements.

Means of securing multiple container boxes require ABS design review as well as onboard
verification by ABS Surveyor. The extent of ABS review is only to confirm that the deck where
the container box is installed has sufficient structural strength to withstand static and dynamic
loads stated by the owner.

TABLE 1
Requirements for Portable Modules

Located / Stacked Accommodation Certified Modules Industrial Exempt Modules

Modules Modules*

Within 30 meters from the a, c, d a, c, d d, e –

Rotary (1)

Not within 30 meters from a, c, d a, c, d d, e –

the Rotary

In Protected Locations (2) a, c, d a, c, d d, e –

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 2 Hull Structure and Outfitting 6-1-2

Located / Stacked Accommodation Certified Modules Industrial Exempt Modules

Modules Modules*

In Hazardous Areas (3) Not Allowed a, c, d d, e d

Stacked >2 high (4) a, c, d a, c, d b, d, e –

Requirements:

a) Full design review to the Offshore Rules

b) Structural design review to the Offshore Rules
c) Survey at Fabricator’s Facility
d) Survey After Installation
e) If the capacity of an available spare breaker is exceeded, review of the electrical interface is
required.
(*): The division is required to be of steel or an equivalent material, but it is not required to be of an “A”

Notes:

1 Buildings located within 30 meters from the rotary require compliance with additional fire protection
requirements.

2 Refers to locations that are protected from waves and hazardous zones, as the Offshore Rules have
additional requirements for other locations.

3 Refers to locations within or adjacent to the ABS-approved hazardous areas for the unit.

4 Refers to the stacking arrangements of the buildings, as all units if stacked over two high are subject
to additional structural/access requirements regardless of service.

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 PART 6
CHAPTER 1
Material, Marine Equipment and Machinery Certification

SECTION 3
Prime Movers

1 General
Prime movers (diesel engines and their turbochargers, gas turbines, steam turbines) for which certification
is required as indicated in 6-1-3/TABLE 1 are to be designed, constructed, tested, certified and installed in
accordance with Part 4, Chapter 2 of the Marine Vessel Rules and this Chapter.

1.1 Objective
1.1.1 Goal
The prime movers covered in this section are to be designed, constructed, operated, and
maintained to:

Goal No. Goal

FIR 1 prevent the occurrence of fire and explosion

FIR 2 reduce the risk to life caused by fire.

SAFE 1.1 minimize danger to persons on board, the vessel, and surrounding equipment/installations from
hazards associated with machinery and systems

AUTO 1 perform its functions as intended and in a safe manner.

AUTO 4 provide the equivalent degree of safety and operability from a remote location as those provided
by local controls.

AUTO 5 provide a safety system that shall automatically lead machinery controlled to a fail-safe state in
response to a fault which may endanger the safety of persons on board, machinery/equipment or
environment.

POW 1 provide safe and reliable storage and supply of fuel/energy/power.

POW 2 provide power to enable the machinery/equipment/electrical installation to perform its required
functions necessary for the safe operation of the vessel.

PROP 2 provide redundancy and/or reliability to maintain propulsion.

The goals in the cross-referenced Rules/Regulations are also to be met.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 3 Prime Movers 6-1-3

1.1.2 Functional Requirements

In order to achieve the above stated goals, the design, construction, installation and maintenance
of prime movers is to be in accordance with the following functional requirements:

Functional Functional Requirements

Requirement No.

Fire Safety (FIR)

FIR-FR1 (SAFE) Piping is to be designed to mitigate hazards due to failure of high-pressure pipe and pipe
joints.

FIR-FR2 (SAFE) Provide safeguards to prevent fire and explosion caused by leakage of flammable liquids.

Safety of Personnel (SAFE)

SAFE-FR1 (FIR) Provide audible notification upon occurrence of fault(s) in the system or abnormal
conditions.

Automation (AUTO)

AUTO-FR1 Provide means to automatically maintain the speed of prime movers driving main or
emergency generator within the specified limits.

AUTO-FR2 Safeguards are to be provided to prevent overspeed.

AUTO-FR3 Provide means to control the prime mover speed within the preset range under all operating
conditions.

Propulsion, Maneuvering, Station Keeping (PROP)

PROP-FR1 Provide protection measures to prevent voltage variations, and to withstand regenerative
power due to over speeding of propulsion system.

Power Generation & Distribution (POW)

POW-FR1 To withstand all loads that are expected during the intended operation.

The functional requirements in the cross-referenced Rules/Regulations are also to be met.

1.1.3 Compliance
A unit is considered to comply with the goals and functional requirements when the applicable
prescriptive requirements are complied with or when an alternative arrangement has been
approved. Refer to Part 1D, Chapter 2.

3 Internal Combustion Engines

3.1 Fuel Oil System

3.1.1 Injection Piping.
All external high pressure fuel delivery lines between the high-pressure fuel pumps and fuel
injectors are to be protected with a jacketed piping system capable of containing fuel from a high-
pressure line failure. A jacketed pipe incorporates an outer pipe into which the high-pressure fuel
pipe is placed, forming a permanent assembly. Metallic hose of an approved type is acceptable for
use as the outer pipe, where outer piping flexibility is required for the manufacturing process of
the permanent assembly. The jacketed piping system is to include means for collection of leakages
and arrangements are to be provided for an alarm to be given of a fuel line failure.

3.1.2 Fuel Oil Return Piping.

When the peak to peak pressure pulsation in the fuel oil return piping from the injectors exceeds
20 bar (20.5 kgf/cm2, 285 psi), jacketing of the return pipes is also required.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 3 Prime Movers 6-1-3

3.1.3 Hot Surfaces

All surfaces with temperatures above 220° C, which may be impinged as a result of a fuel system
failure, are to be properly insulated with non-combustible materials that are impervious to oil.
Insulation material not impervious to oil is to be encased in sheet metal or an equivalent
impervious sheath.

Oil fuel lines are to be screened or otherwise suitably protected to avoid oil spray or oil leakages
onto hot surfaces, into machinery air intakes, or other sources of ignition. The number of joints in
such piping systems is to be kept to a minimum.

3.3 Turbines for Generators

Gas-turbine prime mover driving generators are to meet the applicable requirements in Section 4-2-3 of the
Marine Vessel Rules and in addition are to comply with the following requirements.

3.3.1 Operating Governor

An effective operating governor is to be fitted on prime movers driving main or emergency
electric generators and is to be capable of automatically maintaining speed within the following
limits. Installations requiring different characteristics are subject to ABS technical assessment and
approval

3.3.1(a) Transient Frequency Variations.

The transient frequency variations in the electrical network, when running at the indicated loads
below, are to be within ±10% of the rated frequency when:

i) Running at full load (equal to rated output) of the generator and the maximum electrical
step load is suddenly thrown off:

In the case when a step load equivalent to the rated output of a generator is thrown off, a
transient frequency variation in excess of 10% of the rated frequency is acceptable,
provided the overspeed protective device fitted in addition to the governor, as required by
6-1-3/3.3.2, is not activated.
ii) Running at no load and 50% of the full load of the generator is suddenly thrown on
followed by the remaining 50% load after an interval sufficient to restore the frequency to
steady state.

In all instances, the frequency is to return to within ±1% of the final steady state condition
in no more than five seconds.
3.3.1(b) Frequency Variations in Steady State.
The permanent frequency variation is to be within ±5% of the rated frequency at any load between
no load and full load.

3.3.1(c) Emergency Generator Prime Movers.

For gas turbines driving emergency generators, the requirements of 6-1-3/3.3.1(a) and
6-1-3/3.3.1(b) are to be met. However, for the purpose of 6-1-3/3.3.1(a)ii, where the sum of all
loads that can be automatically connected is larger than 50% of the full load of the emergency
generator, the sum of these loads is to be used as the first applied load.

3.3.2 Overspeed Governor

In addition to the normal operating governor, an overspeed governor is to be fitted which trips the
turbine throttle when the rated speed is exceeded by more than 15%. Provision is to be made for
hand tripping. See 6-1-7/5.13 for pressure-lubricated machines.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 3 Prime Movers 6-1-3

3.3.3 Power Output of Gas Turbines

To satisfy the requirements of 4-3-2/3.1, the required power output of gas turbine prime movers
for drilling unit main service generator sets is to be based on the maximum expected inlet air
temperature.

3.5 Diesel Engines for Generators

Diesel-engine prime movers are to meet the applicable requirements in Section 4-2-1 of the Marine Vessel
Rules and, in addition, are to comply with the following requirements.

3.5.1 Operating Governor

An effective operating governor is to be fitted on prime movers driving main or emergency
electric generators and is to be capable of automatically maintaining the speed within the
following limits. Installations requiring different characteristics are subject to ABS' technical
assessment and approval.

3.5.1(a) Transient Frequency Variations.

The transient frequency variations in the electrical network, when running at the indicated loads
below, are to be within ±10% of the rated frequency when:

i) Running at full load (equal to rated output) of the generator and the maximum electrical
step load is suddenly thrown off,

In the case when a step load equivalent to the rated output of a generator is thrown off, a
transient frequency variation in excess of 10% of the rated frequency is acceptable,
provided the overspeed protective device, fitted in addition to the governor, as required by
6-1-3/3.5.2, is not activated.
ii) Running at no load and 50% of the full load of the generator is suddenly thrown on
followed by the remaining 50% load after an interval sufficient to restore the frequency to
steady state.

In all instances, the frequency is to return to within ±1% of the final steady state condition
in no more than five seconds.
iii) Where the electrical power system is fitted with a power management system and
sequential starting arrangements, the application of loads in multiple steps of less than
50% of rated load in 6-1-3/3.5.1(a)ii) above is permitted, provided it is in accordance with
6-1-3/ FIGURE 1. The details of the power management system and sequential starting
arrangements are to be submitted and its satisfactory operation is to be demonstrated to
the Surveyor.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 3 Prime Movers 6-1-3

FIGURE 1
Reference values for maximum possible sudden power P (%) increases
as a function of brake mean effective pressure, Pme (kPa), at declared
power (four-stroke engines)

3.5.1(b) Frequency Variations in Steady State.

The permanent frequency variation is to be within ±5% of the rated frequency at all loads between
no load and full load.

3.5.1(c) Emergency Generator Prime Movers.

For prime movers driving emergency generators, the requirements of 6-1-3/3.5.1(a) and
6-1-3/3.5.1(b) above are to be met. However, for the purpose of 6-1-3/3.5.1(a)ii), where the sum
of all loads that can be automatically connected is larger than 50% of the full load of the
emergency generator, the sum of these loads is to be used as the first applied load.

3.5.2 Overspeed Governor

In addition to the normal operating governor, each auxiliary diesel engine having a maximum
continuous output of 220 kW and over is to be fitted with a separate overspeed device so adjusted
that the speed cannot exceed the maximum rated speed by more than 15%. Provision is to be made
for hand tripping. See 6-1-7/5.13 for pressure-lubricated machines.

3.7 Prime Movers for Propulsion Generators

In addition to 6-1-3/3.3 and 6-1-3/3.5, prime movers for propulsion generators are to comply with the
following requirements:

3.7.1 Capability
The prime mover rated output is to have adequate overloading and build-up capacity for supplying
the power which is necessary during transitional changes in operating conditions of the electrical
equipment. When maneuvering from full propeller speed ahead to full propeller speed astern with
the unit making full way ahead, the prime mover is to be capable of absorbing a proportion of the
regenerated power without tripping due to overspeed.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 3 Prime Movers 6-1-3

3.7.2 Speed Control

Prime movers of any type are to be provided with a governor capable of maintaining the preset
steady speed within a range not exceeding 5% of the rated full-load speed for load changes from
full-load to no-load.

3.7.3 Manual Controls

Where the speed control of the propeller requires speed variation of the prime mover, the governor
is to be provided with means for local manual control as well as for remote control. For turbines
driving AC propulsion generators, where required by the system of control, the governor is to be
provided with means for local hand control as well as remote adjustment from the control station.

3.7.4 Parallel Operation

In case of parallel operation of generators, the governing system is to permit stable operation to be
maintained over the entire operational speed range of the prime movers.

3.7.5 Protection for Regenerated Power

Braking resistors or ballast consumers are to be provided to absorb excess amounts of regenerated
energy and to reduce the speed of rotation of the propulsion motor. These braking resistors or
ballast consumers are to be located external to the mechanical and electric rotating machines.
Alternatively, the amount of regenerated power may be limited by the action of the control system.

3.9 References
3.9.1 Angles of Inclination
For requirements covering angles of inclination for design condition, refer to 6-1-1/3.5 and 4-1-1/
TABLE 1.

3.9.2 Alarms and Safeguards for Emergency Diesel Engines

For requirements covering alarms and safeguards for emergency diesel engines, refer to
4-3-2/5.17.

3.9.3 Prime Mover driving Emergency Generator

For requirements covering emergency generator prime movers, refer to 4-3-2/5.5.2.

3.9.4 Engine Support Systems

For requirements covering support systems for internal combustion engines, refer to 4-2-5/7 (fuel
oil system), 4-2-6/2 (lubricating oil system), 4-2-6/9 (starting-air system), 4-2-6/11 (cooling-water
system) and 4-2-6/13 (exhaust system).

3.9.5 Internal Combustion Engines designed for Drilling Operations

For requirements covering internal combustion engines solely for drilling operations, refer to
8-2-1/7.

3.9.6 Internal Combustion Engines installed in Hazardous Areas

For requirements covering the installation of internal combustion engines in hazardous areas, refer
to 4-3-6/11.

5 Survey and Certification

Where required, all material, type-testing and unit certification is to be carried out, in the presence of and
to the satisfaction of the Surveyor, at the manufacturer’s plant and reported upon before installation
onboard. 6-1-3/TABLE 1 shows the extent of ABS unit certification services required for each type of
prime mover and its associated equipment. Where a product does not require unit certification, Surveyor
attendance is optional, and the product is to be designed and fabricated to satisfy a recognized industrial
standard and the manufacturer’s specification.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 3 Prime Movers 6-1-3

TABLE 1
Certification Details - Prime Movers

Prime Movers ABS Rule Reference

Approval Tier

Section 1: Internal Combustion Engines

1. Internal Combustion Engines ≥ 100 kW (135 hp), intended for 4/5 6-1-1/1.3, 6-1-1/9.9, MVR
propulsion and aux. services essential for propulsion, maneuvering 4-2-1/1.1, 4-2-1/3,
and safety of the vessel, or required by optional class notation 4-2-1/13.1 - 13.9,
4-2-1/13.11, 4-2-1/15

2. Internal Combustion Engines < 100 kW (135 hp) 1 6-1-3/5, 4-1-2/1, MVR
4-2-1/1.1

3. Internal Combustion Engines ≥ 100 kW (135 hp), intended for 1 4-1-2/3, 6-1-1/1.3, MVR
services not essential for propulsion and aux. services for 4-2-1/1.1, 4-2-1/7
propulsion, maneuvering and safety of the vessel

4. Engines operating on natural gas ≥ 100 kW (135 hp), intended for 4/5 MVR 4-2-1, 5C-8-1/1.1.3,
propulsion and aux. services essential for propulsion, maneuvering 5C-8-A7, 5C-13-1/1.7,
and safety of the vessel 5C-13-10, 5C-13-1/1.9

5. Engines operating on low flashpoint fuels ≥ 100 kW (135 hp), 4/5 MVR 4-2-1, 5C-8-1/1.1.3,
intended for propulsion and aux. services essential for propulsion, 5C-13-1/1.7, 5C-13-1/1.2,
maneuvering and safety of the vessel 5C-13-2/3, 5C-13-10,
5C-8-16/9

Section 2: Turbochargers

6. Turbochargers serving cylinder groups > 2500 kW (Category C) 4/5 MVR 4-2-2/1.1, 4-2-2/3,
4-2-2/5.7, 4-2-2/11.1 - 11.5,
4-2-2/11.7

7. Turbochargers serving cylinder groups >1000 kW and ≤ 2500 kW 3 MVR 4-2-2/5.7, 4-2-2/3,
(Category B) 4-2-2/11.1 - 11.5, 4-2-2/11.7

8. Turbochargers serving cylinder groups ≤ 1000 kW (Category A) 2 MVR 4-2-2/1.1, 4-2-2/11.7,

4-2-2/11.5

Section 3: Gas Turbines

9. Gas turbines ≥ 100 kW (135 hp), intended for propulsion and aux. 5 6-1-3/1, 4-1-2/1, MVR
services essential for propulsion, maneuvering and safety of the 4-2-3/1.1, 4-2-3/5.7,
vessel 4-2-3/13.1 - 13.5

10. Gas turbines that are mass produced per MVR 4-2-3/13.3.2(b) 4 MVR 4-2-3/5.7, 4-2-3/13.1 -
13.5

11. Gas turbines < 100 kW (135 hp) 1 MVR 4-2-3/1.1

12. Gas turbines ≥ 100 kW (135 hp), intended for services not 1 4-1-2/3, 6-1-1/1.3, MVR
essential for propulsion and aux. services for propulsion, 4-2-3/1.1, 4-2-3/7
maneuvering and safety of the vessel

13. Gas Turbines operating on natural gas or other low flashpoint fuels 4/5 MVR 4-2-3, 5C-8-16/8,
≥ 100 kW (135 hp), intended for propulsion and aux. services 5C-8-A8/9.1, 5C-13-10/
essential for propulsion, maneuvering and safety of the vessel A1-9, 5C-8-1/1.1.4,
5C-13-10/5

Section 4: Steam Turbines

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 3 Prime Movers 6-1-3

Prime Movers ABS Rule Reference

Approval Tier

14. Steam turbines ≥ 100 kW (135 hp), intended for propulsion and 4/5 MVR 4-2-4/1.1, 4-2-4/3,
aux. services essential for propulsion, maneuvering and safety of 4-2-4/13.1–13.5
the vessel

15. Steam turbines that are mass produced per 4-2-4/13.3.2(b) 4 MVR 4-2-4/1.1, 4-2-4/3,
4-2-4/13.1 - 13.5

16. Steam turbines < 100 kW (135 hp) 1 6-1-3/5, 4-1-2/1, MVR
4-2-4/1.1

17. Steam turbines ≥ 100 kW (135 hp), intended for services not 1 6-1-3/5, 4-1-2/1, MVR
essential for propulsion and aux. services for propulsion, 4-2-4/1.1, 4-2-4/7
maneuvering and safety of the vessel

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 29

 PART 6
CHAPTER 1
Material, Marine Equipment and Machinery Certification

SECTION 4
Propulsion and Maneuvering Systems

1 General
Propulsion and maneuvering machinery (propulsion shafts and its components, propulsion gears and
clutches, propellers, propulsion and positioning thrusters and steering gears) for which certification is
required as indicated in 6-1-4/ TABLE 1 are to be designed, constructed, tested, certified and installed in
accordance with Part 4, Chapter 3 of the Marine Vessel Rules and this Chapter.

1.1 Objective
1.1.1 Goals and Functional Requirements
The goals and functional requirements in the cross-referenced Rules/Regulations are to be met.

1.1.2 Compliance
A unit is considered to comply with the Goals and Functional Requirements when the applicable
prescriptive requirements are complied with or when an alternative arrangement has been
approved. Refer to Part 1D, Chapter 2.

3 Materials for Propulsion Equipment

Materials for the following equipment intended for main propulsion installation are to be tested in
accordance with the requirements of Chapter 3 of the ABS Rules for Materials and Welding (Part 2):
thrust shafts, line shafts, propeller shafts, shafting for propulsion generators and motors, coupling bolts,
and in the case of direct-connected turbine-driven propulsion generators, fan shrouds, centering and
retaining rings.

Major castings or built-up parts such as frames, spiders and end shields are to be surface-inspected and the
welding is to be in accordance with requirements of Chapter 4 of the above referenced Part 2.

5 Survey and Certification

Where required, all material, type-testing and unit certification is to be carried out in the presence of and to
the satisfaction of the Surveyor at manufacturer’s plant and reported upon before installation onboard.
6-1-4/TABLE 1 shows the extent of ABS unit certification services required for propulsion and
maneuvering machinery. Where a product does not require unit certification, Surveyor attendance is
optional, and the product is to be designed and fabricated to satisfy a recognized industrial standard and the
manufacturer’s specification.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 4 Propulsion and Maneuvering Systems 6-1-4

TABLE 1
Certification Details - Propulsion and Maneuvering Systems*

Propulsion and Maneuvering Systems ABS Type Rule Reference

Approval Tier

Propulsion Shafting

Propulsion shafts, coupling bolts 5 6-1-4/1, MVR 4-3-2/9

Cardan shafts, Couplings 4/5 6-1-4/1, MVR 4-3-2/3.1-3.7,

4-3-2/3.7.2(b), 4-3-2/9,
4-3-2/5.21, 4-3-2/5.19

Coupling bolts constructed to a recognized standard 1 6-1-4/1, MVR 4-3-2/9

Gears and Clutches

Gears and Clutches ≥ 5590 kW (7500 hp) 5 6-1-4/1, MVR 4-3-1/9

Gears and Clutches ≥ 100 kW (135 hp) 4/5 6-1-4/1, MVR

4-3-1/1.1,4-3-1/9

Gears and Clutches < 100 kW (135 hp) 1 6-1-4/1, MVR 4-3-1/9

Propellers

Propellers, fixed and controllable pitch 5 6-1-4/1, MVR 4-3-3/9

Propulsion thrusters 4/5 6-1-4/1, MVR 4-3-3/9

Podded propulsion units 5 6-1-4/1, MVR 4-3-7 and

3-2-14/25

Steering

Steering gears 5 6-1-4/1, MVR 4-3-4/19

Thrusters with optional notations (APS, AMS-NP, PAS, DPS notation) 4/5 6-1-4/1, MVR 4-3-5/1.1,
4-3-5/1.3 and 4-3-5/13, DPS
Guide

Other thrusters 375 kW (500 hp) or less 1 6-1-4/1, MVR 4-3-5/3.3.2

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 PART 6
CHAPTER 1
Material, Marine Equipment and Machinery Certification

SECTION 5
Boilers, Pressure Vessels and Fired Equipment

1 General
Boilers, fired and unfired heaters, pressure vessels and heat exchangers for which certification is required
as indicated in 6-1-5/TABLE 1 are to be designed, constructed, tested, certified and installed in accordance
with Part 4, Chapter 4 of the Marine Vessel Rules and this Chapter.

All boilers, heaters, pressure vessels and heat exchangers within the scope of 6-1-5/1.2 are to be certified
by ABS. Mass-produced pressure vessels, including seamless extruded cylinders and fluid power
cylinders, may be certified by alternative means as described in 4-4-1/1.11 of the Marine Vessel Rules.

1.1 Objective
1.1.1 Goal and Functional Requirements
The goals and functional requirements in the cross-referenced Rules/Regulations are to be met.

1.1.2 Compliance
A unit is considered to comply with the Goals and Functional Requirements when the applicable
prescriptive requirements are complied with or when an alternative arrangement has been
approved. Refer to Part 1D, Chapter 2.

1.1 Application
All pressure vessels for marine systems, including boilers, fired and unfired heaters, pressure vessels and
heat exchangers of the following categories are to be subjected to the requirements of this section:

i) Boilers and steam generators with design pressure over 3.5 bar (3.6 kgf/cm2, 50 psi).
ii) Fired heaters for oil with design pressure over 1 bar (1 kgf/cm2, 15 psi).
iii) Independent pressure vessel tanks for the carriage of liquefied gases
iv) Welded accumulators, regardless of their diameters
v) Accumulators of extruded seamless construction are to be designed, manufactured and tested in
accordance with a recognized standard for this type of pressure vessel subject to the requirements
in 4-4-1/15 of the Marine Vessel Rules.
vi) Other pressure vessels and heat exchangers specified in 6-1-5/TABLE 3, having design pressure,
temperature and volume as defined in 6-1-5/ TABLE 2. Group II pressure vessels and heat
exchangers under 150 mm (6 in.) in diameter are not required to comply with the requirements of

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 5 Boilers, Pressure Vessels and Fired Equipment 6-1-5

this section. Acceptance of them is based on manufacturer’s guarantee of physical properties and
suitability for the intended service, provided the installation is carried out to the satisfaction of the
Surveyor.
vii) Boilers and fired heaters not included above, fired inert gas generators and incinerators are subject
to the requirements of 4-4-1/15 of the Marine Vessel Rules only.

1.3 Grouping of Boilers and Pressure Vessels

Boilers and pressure vessels are categorized in 6-1-5/TABLE 3 to specify the degree of inspection and
testing required during the certification process.

3 Materials for Group I Boilers, Heaters, Pressure Vessels and Heat

Exchangers
Materials for Group I boilers, heaters, pressure vessels and heat exchangers are to be tested in accordance
with the requirements of Chapter 3 of the ABS Rules for Materials and Welding (Part 2).

5 Survey and Certification

Where required, all material, type-testing and unit certification is to be carried out, in presence of and to
the satisfaction of the Surveyor, at manufacturer’s plant and reported upon before installation onboard.
6-1-5/TABLE 1 shows the extent of ABS unit certification services required for each boiler, heater,
pressure vessel and heat exchanger. Where a product does not require unit certification, Surveyor
attendance is optional, and the product is to be designed and fabricated to satisfy a recognized industrial
standard and the manufacturer’s specification.

TABLE 1
Certification Details - Boilers, Pressure Vessels and
Fired Equipment*

Boilers, Pressure Vessels and Fired Equipment ABS Rule Reference

Approval Tier

Section 1: Group I

Group I boilers and pressure vessels 5 6-1-5/1.3, 6-1-5/3, 6-1-5/5

Section 2: Group II

Fired pressure vessels 4/5 6-1-5/1.3, 6-1-5/3, 6-1-5/5

Non-fired pressure vessels 4/5 6-1-5/1.3, 6-1-5/3, 6-1-5/5

Section 3: Inert Gas Generators & Incinerators

Inert gas generators, incinerators 2 6-1-5/1.3, 6-1-5/3, 6-1-5/5

*Notes: Reference Part 4, Chapter 4 of the Marine Vessel Rules and Chapter 3 of the ABS Rules for Materials and
Welding (Part 2).

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 33

Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 5 Boilers, Pressure Vessels and Fired Equipment 6-1-5

TABLE 2
Pressure Vessels and Heat Exchangers*

Design Pressure Design Temperature Volume

bar kgf/cm psi °C °F m3 ft3

2

a) Pressure vessels and heat > 1.0 > 1.0 > 15 – all all – all all
exchangers for toxic and
corrosive substances (see
4-1-1/3.9)

b) Pressure vessels, heat > 6.9 >7 > 100 – all all – all all
exchangers and heaters other
than a)

c) Pressure vessels, heat > 1.0 > 1.0 > 15 and > 149(1) > 300(1) and > 0.14 >5
exchangers and heaters other > 66(2) > 150(2)
than a) and b) > 90(3) > 200(3)

Notes:

* Reference Part 4, Chapter 4 of the Marine Vessel Rules and Chapter 3 of the ABS Rules for Materials and Welding
(Part 2).

1 Applicable to steam, gas or vapor; and to liquids other than fuel oil, lubricating oil, hydraulic oil and thermal
oil.

2 Applicable to fuel oil.

3 Applicable to lubricating oil, hydraulic oil and thermal oil.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 5 Boilers, Pressure Vessels and Fired Equipment 6-1-5

TABLE 3
Grouping of Boilers, Pressure Vessels and Fired Equipment*

Grp Type Design Pressure Design Volume Thickness

Temperature

bar kgf/cm2 psi °C °F m3 ft3 mm in.

I a) Boilers and > 3.5 > 3.6 > 50 – all all – all all – all all
steam
generators

b) Pressure > 41.4 > 42.2 > or >371 (1) >700 (1) and all all or > 38 > 1.5
vessels and 600 >204 (2) >400 (2)
heat
exchangers,
other than d)
and e)(6)

c) Fired > 41.4 > 42.2 > – all all – all all – all all
heaters for oil 600

d) Liquefied ≥ 2.1 ≥ 2.1 ≥ 30 – all all – all all – all all

gas pressure
vessel cargo
tanks(6)

e) Pressure > 1.0 > 1.0 > 15 – all all – all all – all all
vessels and
heat
exchangers for
toxic or
corrosive
substances (6)

II a) Fired heater ≤ 41.4 ≤ 42.2 ≤ – all all – all all – all all
for oil and and 600
> 1.0 > 1.0 and
> 15

b) Pressure ≤ 41.4 ≤ 42.2 ≤ and ≤ 371 (1) ≤700 (1) and all all and ≤ 38 ≤ 1.5
vessels and and and 600 ≤ 204 (2) ≤400 (2)
heat > 6.9 >7 and
exchangers, >
other than 100
Group I b(6)

c) Pressure ≤ 6.9 ≤7 ≤ and > 149 (3) > 300 and > 0.14 >5 and ≤ 38 ≤ 1.5
vessels and and and 100 > 66(4) (3)

heat > 1.0 > 1.0 and > 90(5) > 150
(4)
exchangers, > 15
other than > 200
Group II b(6) (5)

Notes:

* Reference Part 4, Chapter 4 of the Marine Vessel Rules and Chapter 3 of the ABS Rules for Materials and Welding
(Part 2).

1 Steam, gas or vapor, other than toxic or corrosive substances.

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 35

Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 5 Boilers, Pressure Vessels and Fired Equipment 6-1-5

2 Liquids, other than toxic and corrosive substances.

3 Steam, gas or vapor, and liquids excluding fuel oil, lubricating oil and thermal oil; other than toxic or corrosive
substances.

4 Fuel oil.

5 Lubricating oil and thermal oil.

6 Internal diameter ≥ 150 mm (6 in.). Vessels with smaller diameter are outside the scope of this Section.

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 36

 PART 6
CHAPTER 1
Material, Marine Equipment and Machinery Certification

SECTION 6
Piping Systems

1 General

1.1 Objective
1.1.1 Goals
The piping systems covered in this section are to be designed, constructed, operated, and
maintained to:

Goal No. Goal

SAFE 1.1 minimize danger to persons on board, the vessel, and surrounding equipment/installations from
hazards associated with machinery and systems.

Materials are to be suitable for the intended application in accordance with the following goal in
support of the Tier 1 goal as listed above.

Goal No. Goal

MAT 1 The selected materials’ physical, mechanical and chemical properties are to meet the design
requirements appropriate for the application, operating conditions and environment.

The goals in the cross-referenced Rules/Regulations are also to be met.

1.1.2 Functional Requirements

In order to achieve the above stated goals, the design, construction, installation and maintenance
of the piping systems are to be in accordance with the following functional requirements:

Functional Functional Requirements

Requirement No.

Material (MAT)

MAT-FR1 (SAFE) Gauges, detectors, fluid power cylinders and transmitters are to be capable of withstanding
the most extreme combination of design pressures, temperatures, and loadings.

MAT-FR2 Piping material is to be compatible with the fluid media it conveys.

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 37

Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 6 Piping Systems 6-1-6

Functional Functional Requirements

Requirement No.

Material (MAT)

Safety of Personnel (SAFE)

SAFE-FR1 Piping is to safely contain the fluid media it conveys and able to withstand the most severe
condition of coincident design pressures, temperatures, vibrations and loadings.

The functional requirements in the cross-referenced Rules/Regulations are also to be met.

1.1.3 Compliance
A unit is considered to comply with the Goals and Functional Requirements when the applicable
prescriptive requirements are complied with or when an alternative arrangement has been
approved. Refer to Part 1D, Chapter 2.

Materials used for piping system components, for which certification is required as indicated in this
Section, are to be produced, tested, and certified in accordance with ABS Rules for Materials and Welding
(Part 2), as applicable and this Section.

Piping system components for which certification is required as indicated in 6-1-6/TABLE 1 and 6-1-6/
TABLE 2 are to be designed, constructed, tested, certified and installed in accordance with Part 4 Chapter
2 and this Section.

Piping systems associated with steering gear systems are to be in accordance with Section 4-3-4 of the
Marine Vessel Rules.

Piping systems, such as steam, exhaust and feed systems, associated with boilers are to be in accordance
with the applicable requirements of Part 4, Chapters 4 and 6 of the Marine Vessel Rules.

Class I, II and III piping systems are defined in 4-2-1/TABLE 1.

3 Pipes

3.1 Manufacturer’s Certification

Where indicated as 'required' in 6-1-6/Table 2, the manufacturer is to certify that the piping component
complies with the standard to which the component is designed, fabricated and tested, and to report the
results of tests. For Class III piping components, manufacturer's trademark, pressure/temperature rating
and material identification, as applicable, stamped or cast on the component and verifiable against the
manufacturer's catalog or similar documentation is sufficient.

3.3 Identification
For all Class I, II and III piping systems, metallic pipes are to have a temporary identification for
traceability during fabrication. Plastic pipes are to be permanently marked with identification as required in
7-1-3/13.5.

3.5 Plastic Piping

Manufacturing of plastic pipes is to be in accordance with 4-2-2/7.9. Where the manufacturer does not
have a certified quality system in accordance with the ABS Rules for Conditions of Classification -
Offshore Units and Structures (Part 1B) or ISO 9001 (or equivalent), tests required by these Rules are to
be carried out using samples from each batch of pipes being supplied for use aboard the unit, and in the
presence of the Surveyor (see 4-2-2/7.9).

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 38

Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 6 Piping Systems 6-1-6

5 Piping Components other than Pipes

Piping components other than pipes are to be certified in accordance with 6-1-6/TABLE 1 and the
following.

5.1 Pipe Fittings and Valves

5.1.1 Design Review
Design approval is a part of the ABS certification process and where indicated as ‘required’ in
6-1-6/TABLE 2, pipe fittings and valves are to meet an applicable recognized standard, or are to
be design-approved by ABS. For the latter purpose, pipe fittings and valves are to be evaluated for
their adequacy for the rated pressures and temperatures and, as applicable, type inspection and
testing are to be conducted as part of the design evaluation process. See also 4-2-2/5.7,4-2-2/7.5
and 6-1-6/3.5.

5.1.2 Manufacturer’s Certification

Where indicated as ‘required’ in 6-1-6/TABLE 2, the manufacturer is to certify that the pipe
fittings and valves comply with the standard to which the component is designed, fabricated and
tested, and to report the results of tests. For Class III components, manufacturer’s trademark,
pressure/temperature rating and material identification, as applicable, stamped or cast on the
component and verifiable against the manufacturer’s catalog or similar documentation is
sufficient.

5.1.3 Identification
Where indicated as 'permanent' in 6-1-6/TABLE 2, the pipe fittings and valves are to bear
permanent identification, such as manufacturer's name or trademark, standard of compliance,
material identity, pressure rating, etc., as required by the standard of compliance or the
manufacturer's specification. Such markings may be cast or forged integral with, stamped on, or
securely affixed by nameplate on the component, and are to serve as a permanent means of
identification of the component throughout its service life.

5.1.4 Welded Non-Standard Valves and Fittings

Non-standard steel valves and fittings fabricated by means of fusion welding are to comply with
the requirements of Chapter 4 of the ABS Rules for Materials and Welding (Part 2). However,
after a manufacturer’s procedure in the fabrication of equipment of this kind has been
demonstrated by tests to the satisfaction of a Surveyor to ABS, subsequent tests on the product
need not be witnessed. Manufacturer’s guarantee that the Rules are complied with are acceptable
for other valves and fittings which conform to standards of the American National Standards
Institute (ANSI) or other recognized standards.

5.1.5 Shell Valves

Shell valves are to be designed, constructed, and tested in accordance with 4-2-2/21and
6-1-6/7.3.1.

5.1.6 Pipe Joints

Pipe joints and mechanical joints are to be designed, constructed and tested in accordance with
4-6-2/5.5 and 4-6-2/5.9 of the Marine Vessel Rules, respectively. See 4-2-1/11.11 and 4-2-1/11.13.

The installation of pipe joints and mechanical joints is to be in accordance with the manufacturer’s
assembly instructions. Where special tools and gauges are required for installation of the joints,
these are to be specified and supplied as necessary by the manufacturer. These special tools are to
be kept onboard.

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 6 Piping Systems 6-1-6

5.3 Flexible Hoses

Hoses for which design review and type-testing is required as indicated in 6-1-6/TABLE 1 are to be
designed, constructed, and tested in accordance with 4-2-1/11.29.

5.5 Vent Heads and Pressure/Vacuum Valves

Vent heads for which design review and type-testing is required as indicated in 6-1-6/TABLE 1 are to be
designed, constructed and tested in accordance with 4-2-3/2.9.

When provided for the protection of crude oil tanks, pressure/vacuum valves are to be designed,
constructed and tested in accordance with IMO Resolution MSC/Circ. 677 and MSC/Circ. 450/Rev. 1.

5.7 Gauges, Detectors, and Transmitters

Gauges, detectors, and transmitters for which design review is required as indicated in 6-1-6/TABLE 1 are
to be designed to withstand the design pressure of the system to which they are connected and the material
is to be suitable for the type of fluid being measured.

5.9 Fluid Power Cylinders

Fluid power cylinders and systems, including valve actuators, for which design review is required as
indicated in 6-1-6/TABLE 1 are to be designed in accordance with 4-2-2/19.

The physical and chemical characteristics of materials entering into the construction of hydraulic and
pneumatic power cylinders are to be in accordance with the applicable requirements of Section 2-3-1 of the
ABS Rules for Materials and Welding (Part 2) or such other appropriate material specification as may be
approved in connection with a particular design.

Copies of certified mill test reports are to be made available to the Surveyor upon request.

Ordinary cast iron or similar materials (elongation less than 12%) are not to be used for cylinders which
may be subjected to shock loading.

5.11 Pumps
Pumps are to be certified in accordance with 6-1-6/TABLE 1.

5.13 Non-standard Components

Components not manufactured to a recognized national standard may be considered for acceptance based
on manufacturers’ specified pressure and temperature ratings and on presenting evidence, such as design
calculations or type test data, that they are suitable for the intended purpose. For Classes I and II piping
applications, drawings showing details of construction, materials, welding procedures, etc., as applicable,
are to be submitted for such components, along with the basis for the pressure and temperature ratings.
Nonstandard components are preferably to be Type Approved (see 1B-1-A2/5 of these Rules).

7 Survey and Certification

Where required, all material, type-testing and unit certification is to be carried out, in the presence of and
to the satisfaction of the Surveyor, at manufacturer’s plant and reported upon before installation onboard.
6-1-6/TABLE 1 shows the extent of services required for each pump, piping, and pipe component. Where a
product does not require unit certification, Surveyor attendance is optional, and the product is to be
designed and fabricated to satisfy a recognized industrial standard and the manufacturer’s specification.

7.1 Survey and Certification of Pipes

Pipes intended for use in Class I and Class II piping systems are to be tested at the mill, in the presence of
and to the satisfaction of the attending Surveyor, in accordance with the requirements of Chapter 3 of the
ABS Rules for Materials and Welding (Part 2) or such other appropriate material specification as may be
approved in connection with a particular design (see 4-2-6/3.5).

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 6 Piping Systems 6-1-6

The material surfaces are to be examined by the Surveyor when specially requested by the purchaser. See
also 4-6-7/3.5.1 of the Marine Vessel Rules.

The pipes are to be reasonably straight, free from defects, and have a workmanlike finish. At a minimum,
the finished pipe is to be visually inspected at the same frequency as that required for the tension test
specified in 2-3-12/TABLE 3 for the applicable grade. Welding repair to the pipe is not to be carried out
without the purchaser’s approval and is to be to the satisfaction of the Surveyor.

Pipes intended for use in Class I and Class II piping systems are to be tested at the mill, in the presence of
and to the satisfaction of the attending Surveyor or alternatively produced under an ABS certified Product
Quality Assurance (PQA).

7.3 Survey and Certification of Piping Components other than Pipes

Where indicated in 6-1-6/TABLE 1 and 6-1-6/TABLE 2, the piping component is to be certified by ABS.
This involves design approval of the component, as applicable, and testing in accordance with the standard
of compliance at the manufacturer’s plant.

7.3.1 Survey and Certification of Shell Valves

All valves intended for installation on the side shell at or below the deepest load waterline,
including those at the sea chests, are to be hydrostatically tested in presence of and to the
satisfaction of the attending Surveyor, before installation.

The valve housing of each valve is to be subjected to a pressure of at least 5 bar (5.1 kgf/cm2, 72.5
psi). No leakage is permitted and holding time is as follows:

● 15 seconds for size up to 50 mm (2 inch)

● 60 seconds for sizes 65 mm ~ 150 mm (2.5 inch ~ 6 inch)
● 120 seconds for sizes 200 mm ~ 300 mm (8 inch ~ 12 inch)
● 300 seconds for sizes 350 mm (14 inch) and larger

The valve assembly is to be subjected to a hydrostatic seat leakage test. The test is to be performed
with closed valve with the other end open to atmosphere. The pressure is to be applied
independently on each side. Test pressure is not to be less than 5 bar (5.1 kgf/cm 2, 72.5 psi).
Holding time is 5 minutes for all sizes.

7.3.2 Survey and Certification of Pumps

Regardless of their capacity, the following pumps are required to be fabricated and tested in the
presence of and to the satisfaction of the attending Surveyor:

● Ballast pumps
● Bilge pumps
● Fire pumps, including emergency fire pumps
● Other fire fighting service pumps, such as, pumps for fixed water-based systems, or
equivalent, local application fire-fighting systems, sprinkler systems, raw water pumps,
booster pumps, etc.
● Hydraulic pumps for steering gear, anchor windlass and controllable pitch propellers, as
applicable
● Fuel transfer pumps or fuel supply pumps (for self-propelled units and for dynamically
positioned units only)
● Lubricating oil pumps (for self-propelled units and for dynamically positioned units only)

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 6 Piping Systems 6-1-6

● Fuel service pumps, booster pumps, etc. (for self-propelled units and for dynamically
positioned units only with propulsion diesel engines with bores > 300 mm)
● Sea water and freshwater cooling pumps (for self-propelled units and for dynamically
positioned units only with propulsion diesel engines with bores > 300 mm)

The pumps are to meet the hydrostatic and capacity test requirements in 6-1-6/7.3.2(a) and
6-1-6/7.3.2(b) and the tests are to be carried out at the manufacturer’s plant in the presence of the
Surveyor.

7.3.2(a) Hydrostatic Tests.

The pumps are to be hydrostatically tested to a pressure of at least 1 . 5P, where P is the maximum
working pressure of the pump. If it is desired to conduct the hydrostatic test on the suction side of
the pump independently from the test on the discharge side, the test pressure on the suction side is
to be at least 1 . 5Ps, where Ps is the maximum pressure available from the system at the suction
inlet. In all cases, the test pressure for both the suction and the discharge side is not to be less than
4 bar.

7.3.2(b) Capacity Tests.

Pump capacities are to be checked with the pump operating at design conditions (rated speed and
pressure head). For centrifugal pumps, the pump characteristic (head-capacity) design curve is to
be verified to the satisfaction of the Surveyor. Capacity tests may be waived if previous
satisfactory tests have been carried out on similar pumps.

7.3.2(c) Relief Valve Capacity Test.

For positive displacement pumps with an integrated relief valve, the valve’s setting and full flow
capacity corresponding to the pump maximum rating is to be verified. The operational test for
relief valve capacity may be waived if previous satisfactory tests have been carried out on similar
pumps.

7.3.3 Certification Based on the Type Approval Program

7.3.3(a) Pipes
For pipes which are required to be ABS certified in accordance with 6-1-6/TABLE 1, the
manufacturer may request that ABS approve and list them under the Type Approval Program
described in Appendix 1B-1-A2. Upon approval under 1B-1-A2/5.5 (PQA) and listing under this
program, the pipes are not required to be surveyed and certified each time they are manufactured
for use on board a unit.

To be considered for approval under this program, the manufacturer is to operate a quality
assurance system that is certified for compliance with a recognized quality standard. In addition,
quality control of the manufacturing processes is to cover all the requirements of inspection and
tests required by the Rules and applicable pipe standard, in accordance with 1B-1-A2/5.5.

7.3.3(b) Pipe Fittings and Valves

For pipe fittings and valves which are not required to be certified but are required to be design
approved in accordance with 6-1-6/TABLE 1, the manufacturer may request that ABS approve
and list the component as a Design Approved Product described in 1B-1-A2/5.1. The design is to
be evaluated in accordance with 6-1-6/5. Upon approval and listing, and subject to renewal and
updating of the certificates as required by 1B-1-A2/5.7, the manufacturer need not submit the
design of the component for approval each time it is proposed for use on board a unit. The
manufacturer may also request that the product be approved and listed under the Type Approval
Program. In this case, in addition to the design approval indicated above, the manufacturer is to
provide documented attestation that the product is manufactured to consistent quality and to the
design and specifications to which it is approved. See 1B-1-A2/5.3 (AQS)/(RQS) or 1B-1-A2/5.5
(PQA).

7.3.3(c) Pumps

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 6 Piping Systems 6-1-6

As an alternative to certification specified in 6-1-6/7.3.2, for mass-produced pumps, the

manufacturer may request that ABS design assesses and list the pump under the Type Approval
Program. To be design assessed under this program:
i) The manufacturer may submit drawings and apply for a Product Design Assessment
based on compliance with recognized standards as specified in 1B-1-A2/5.1,
ii) A sample of the pump type is to be subjected to hydrostatic and capacity tests, and relief
valve capacity test specified in 6-1-6/7.3.2. Pumps so assessed may be accepted by ABS
for listing on ABS website under the Product Design Assessment (PDA) index.
iii) The manufacturer is to operate a quality assurance system which is to be certified for
compliance with a quality standard in accordance with 1B-1-A2/5.3 (AQS)/(RQS) or
1B-1- A2/5.5 (PQA). The quality control plan is to have provision to subject each
production unit of the pump to tests specified in 6-1-6/7.3.2 and the manufacturer is to
submit record of such tests to the local ABS office who finalizes the Unit Certification.
Pumps that meet this requirement are listed on the ABS website under the Type Approved
Product (PTA) index.

TABLE 1
Certification Details - Piping System Components

Piping System Components ABS Rule Reference

Approval Tier

Pipes - Steel; Class I 4/5 6-1-6/3.1

Pipes - Steel; Class II 4/5 6-1-6/3.1

Pipes - Steel; Class III 1 6-1-6/3.1

Pipes, pipe fittings and pipe joints Level I and II - Plastic 4/5 6-1-6/3.5 and 4-2-2/7.9,
MVR 4-6-3/9, 4-2-2/7.5.6

Pipe fittings of standard design - Flanges, elbows, tees, expansion joints, 1 6-1-6/5
etc., and valves; Classes I and II

Pipe fittings of non-standard design - Flanges, elbows, tees, expansion 2 6-1-6/5

joints, etc., and valves; Classes I and II

Pipe fittings - Flanges, elbows, tees, expansion joints, etc., and valves; 1 6-1-6/5.1.2
Class III

Pipe fittings - Mechanical joints 2 6-1-6/5.1.6

Fusion welded non-standard valves and fittings 2 6-1-6/5.1.4

(1)
Shell valves 5 6-1-6/5.1.5, 6-1-6/7.3.1

Flexible Hoses (not fire hoses) 2 6-1-6/5.3

Vent heads, pressure/vacuum valves 2 6-1-6/5.5

Gauges, detectors and transmitters 2 6-1-6/5.7

Fluid power cylinders and systems, including valve actuators 2 6-1-6/5.9

Pumps related to propulsion diesel engines (bore >300 mm) (11.8 in.) 4/5 6-1-6/7.3.2
and gas turbines and gears - fuel, cooling water, lube oil services(1)

Pumps related to propulsion steam plant and gears - fuel oil, lube. Oil, 4/5 6-1-6/7.3.2
condensate, main circulating, feed water services(1)

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 6 Piping Systems 6-1-6

Piping System Components ABS Rule Reference

Approval Tier

Hydraulic pumps of steering gears, controllable pitch propellers, anchor 4/5 6-1-6/7.3.2
windlass(1)

Pumps for fire fighting, ballast and bilge(1) 4/5 6-1-6/7.3.2

Air compressors 1

Notes:

1 Design review is only required when applying for Type Approval Program.

TABLE 2
Piping Classes and Certification

Piping Class Design Approval (1) Manufacturer’s Identification (1) Unit Certification
Component Certification (1)

Pipes I, II Not applicable (3) Required Temporary (3) Required (2)

III Not applicable (3) Required Temporary (3) Not required (3)

Pipe fittings I, II Required (4, 6) Required Permanent Not required

III Not required (5 ,6) Required Permanent Not required

(4)
Valves I, II Required Required Permanent Not required

III Not required (5) Required Permanent Not required

Notes:

1 See 6-1-6/3.1, 6-1-6/3.3, 6-1-6/5.1.1, 6-1-6/5.1.2 and 6-1-6/5.1.3.

2 Except hydraulic piping.

3 Except for plastic piping. See 6-1-6/3.5.

4 Where not in compliance with a recognized standard.

5 Documentary proof of pressure/temperature rating is required. See 6-1-6/5.13.

6 Design of flexible hoses and mechanical pipe joints is to be approved in each case. See 4-2-1/11.29 of these
Rules and 4-6-2/5.9 of the Marine Vessel Rules, respectively.

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 PART 6
CHAPTER 1
Material, Marine Equipment and Machinery Certification

SECTION 7
Electrical Systems and Control Equipment

1 Objective

1.1 Goals
The electrical systems and control equipment covered in this section is to be designed, constructed,
operated, and maintained to:

Goal No. Goal

POW 1 Provide safe and reliable storage and supply of fuel/energy/power.

POW 2 Provide power to enable the machinery/equipment/electrical installation to perform its required
functions necessary for the safe operation of the unit.

POW 4 Enable all electrical services required for safety to be available during emergency conditions.

POW 5 Enable supply/power for essential services to be restored after malfunction.

PROP 1 provide sufficient thrust/power to move or maneuver the unit when required.

FIR 3 Reduce the risk of damage caused by fire to the ship, its cargo and the environment.

SAFE 1.1 Minimize danger to persons on board, the unit, and surrounding equipment / installations from
hazards associated with machinery and systems.

MGMT 5.1 Design and construct unit, machinery, and electrical systems to facilitate safe access, ease of
inspection, survey, and maintenance.

AUTO 1 Perform its functions as intended and in a safe manner.

AUTO 2 Indicate the system operational status and alert operators of any essential machinery/systems
deviate from its defined design/operating conditions or intended performance.

Materials are to be suitable for the intended application in accordance with the following goals and support
the Tier 1 goals as listed above.

Goal No. Goal

MAT 1 The selected materials’ physical, mechanical and chemical properties are to meet the design
requirements appropriate for the application, operating conditions and environment.

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Chapter 1 Material, Marine Equipment and Machinery Certification
Section 7 Electrical Systems and Control Equipment 6-1-7

The goals in the cross-referenced Rules/Regulations/Standards are also to be met.

1.2 Functional Requirements

In order to achieve the above-stated goals, the design, construction, installation and maintenance of the
electrical systems and control equipment to which this Section applies are to be in accordance with the
following functional requirements:

Functional Functional Requirements

Requirement No.

Propulsion, Maneuvering, Station Keeping (PROP)

PROP-FR1 Provide overspeed protection for propulsion machines to avoid loss of propulsion.

Power Generation and Distribution (POW)

POW-FR1 (AUTO) Provide means to automatically maintain the speed of prime movers driving the main and auxiliary
power generation systems.

POW-FR2 (AUTO) Electrical generators are to be provided with means to automatically regulate the output voltage to
the rated value.

POW-FR3 When it is intended that two or more generators, transformers, or converters be operated in parallel,
means are to be provided to divide the reactive power equally between the devices in proportion to
their capacities.

POW-FR4 (AUTO) The generating set is to maintain torsional vibration levels within the design values rated for the
power generation system.

POW-FR5 Provide sufficiently sized main and branch busbars to carry all of the simultaneous loads that they
supply.

POW-FR6 Provide arrangement of busbar so that the temperature rise does not affect the normal operation of
electrical loads connected.

POW-FR7 (AUTO) Provide under-voltage protection to prevent malfunction of the electrical power consumers.

POW-FR8 (AUTO) Provide starting sequence for auto-starters to prevent erroneous operation.

POW-FR9 Battery systems and UPS are to be designed to maintain continuity of load power for essential and
emergency electrical power consumers.

POW-FR10 Provide means to prevent unintended discharge of batteries.

(AUTO)

POW-FR11 Provide cables with sufficient current carrying capacity to support connected loads and their
overload protection.

POW-FR12 Provide measures to protect equipment from internal damages.

(AUTO)

POW-FR13 Provide means to regulate transformer output voltage to achieve necessary performance
characteristics of the converter unit in which the transformer is used.

Materials (MAT)

MAT-FR1 (POW) Be of design and be constructed of materials to withstand the marine and operating environment,
maximum design ambient temperature and stresses without deterioration.

MAT-FR2 (FIR) Cables and electrical conductors are to be constructed of high conductivity and flame-retardant
material and sized to prevent any damage due to temperature rise during normal operation.

Fire Safety (FIR)

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Chapter 1 Material, Marine Equipment and Machinery Certification
Section 7 Electrical Systems and Control Equipment 6-1-7

Functional Functional Requirements

Requirement No.

FIR-FR1 Provide fire-extinguishing systems for effective containment and extinction of fire in electrical
equipment.

Safety of Personnel (SAFE)

SAFE-FR1 Provide protection to prevent accidental contact with live parts of the assembly.

SAFE-FR2 Provide enclosure with suitable degree of protection against ingress of foreign objects and liquids
based on location and personnel accessibility of installation.

SAFE-FR3 Provide arrangements to prevent electric shock.

SAFE-FR4 Provide means to prevent slips, trips and falls while working on the equipment with panels for
operation.

SAFE-FR5 Cable connectors are to withstand the marine environment and maximum design ambient
temperature.

SAFE-FR6 Circuit protection devices are to be able to withstand fault currents.

SAFE-FR7 The enclosure construction of switchgear and control gear assemblies is designed to be earthed and
completely assembled for safety.

SAFE-FR8 Provide locking arrangements in circuit operating mechanism systems for reasons of safety and
convenience of operation.

SAFE-FR9 The insulation and location of switchgear and control gear assemblies is to be designed to protect
personnel operating the equipment considering the internal arc.

SAFE-FR10 Provide enclosed means of ventilation for machinery and equipment to prevent personnel injury or
entrance of foreign matter.

SAFE-FR11 Provide safety design for water-air cooler to prevent the water leakage.

Safety Management (MGMT)

MGMT-FR1 Provide accessibility to all the parts of the equipment requiring inspection, adjustment, or
replacement.

MGMT-FR2 Provide means of disconnecting the electrical equipment from power source for maintenance.

MGMT-FR3 Provide information on electrical equipment for traceability and maintenance.

Automation (Control, Monitoring and Safety Systems) (AUTO)

AUTO-FR1 (POW/ Provide suitable insulation based on maximum continuous operating temperatures.
SAFE)

AUTO-FR2 (POW/ Rotating electrical machines are to be able to withstand overload, overcurrent and short circuit
SAFE) conditions so that the overall operational integrity of the motor is not affected during service.

AUTO-FR3 (SAFE) Provide means to prevent circulating currents from passing between the rotor shaft and the bearings.

AUTO-FR4 (SAFE) Provide the required lubrication for rotating machine’s shaft bearings at all rated operating
conditions.

AUTO-FR5 (SAFE) Provide a means to prevent moisture condensation in the machine when idle.

AUTO-FR6 Instrumentation to control the main and emergency sources of power are to be provided to maintain
the power supply for the required loads.

AUTO-FR7 Provide means to monitor and alarm parameters for the protection of equipment.

AUTO-FR8 Provide safety measures and alarms to protect the electrical distribution system from harmonics.

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Chapter 1 Material, Marine Equipment and Machinery Certification
Section 7 Electrical Systems and Control Equipment 6-1-7

Functional Functional Requirements

Requirement No.

AUTO-FR9 Provide means to monitor internal temperatures of the equipment and alarm when the normal
operating temperatures are exceeded to prevent damage to the equipment.

AUTO-FR10 All critical parameters for power generation and distribution equipment are to be monitored and
(SAFE) protections are to be provided to avoid damage to equipment and onboard personnel.

The functional requirements covered in the cross-referenced Rules/Regulations/Standards are also to be

met.

1.3 Compliance
A unit is considered to comply with the goals and functional requirements when the prescriptive
requirements are complied with or when an alternative arrangement has been approved. Refer to Part 1D,
Chapter 2.

2 General
Electrical equipment and machinery for which certification is required as indicated in 6-1-7/19.23 TABLE
1 are to be designed, constructed, tested, certified and installed in accordance with this Chapter.

2.1 Insulation Material

For the purpose of these requirements, insulating material is designated as follows.

2.1.1 Class A Insulation

Materials or combinations of materials such as cotton, silk and paper when suitably impregnated
or coated or when immersed in a dielectric liquid such as oil. Other materials or combinations of
materials can be included in this class if, by experience or accepted tests, they can be shown to be
capable of operation at 105° C (221° F).

2.1.2 Class B Insulation

Materials or combinations of materials such as mica, glass fiber, etc., with suitable bonding
substances. Other materials or combinations of materials, not necessarily inorganic, can be
included in this class if, by experience or accepted tests, they can be shown to be capable of
operation at 130° C (266° F).

2.1.3 Class E Insulation

Materials or combinations of materials which, by experience or accepted tests, can be shown to be
capable of operation at 120° C (248° F) (materials possessing a degree of thermal stability
allowing them to be operated at a temperature 15° C (27° F) higher than Class A materials).

2.1.4 Class F Insulation

Materials or combinations of materials such as mica, glass fiber, etc., with suitable bonding
substances. Other materials or combinations of materials, not necessarily inorganic, can be
included in this class if, by experience or accepted tests, they can be shown to be capable of
operation at 155° C (311° F).

2.1.5 Class H Insulation

Materials or combinations of materials such as silicone elastomer, mica, glass fiber, etc., with
suitable bonding substances such as appropriate silicone resins. Other materials or combinations
of materials can be included in this class if, by experience or accepted tests, they can be shown to
be capable of operation at 180° C (356° F).

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Chapter 1 Material, Marine Equipment and Machinery Certification
Section 7 Electrical Systems and Control Equipment 6-1-7

2.1.6 Insulation for Temperature Above 180° C (356° F)

Materials or combinations of materials which by experience or accepted tests can be shown to be
capable of satisfactory operation at temperature over 180° C (356° F) are acceptable subject to
ABS technical assessment and approval. Supporting background experience or report of tests
conducted in accordance with a recognized standard ascertaining their suitability for the intended
application and temperature operation are to be submitted for review.

2.3 Accessibility
The design and arrangement of electrical apparatus is to provide accessibility to parts requiring inspection
or adjustment. Refer to 7A-1-5/7.13.3. Armature and field coils, rotors and revolving fields are to be
removable and where air ducts are used, there are to be means of access.

2.5 Handrails
Insulated handrails or handles are to be provided for the equipment which are required to be operational
while the unit is experiencing motion or inclination. These may include the main and emergency
switchboards, motor control centers, distribution boards for essential and emergency services, as well as
services for specific functions in association with the unit's class notation. See also 6-1-7/9.13,
6-1-7/12.5.5.

3 Plans and Data to be Submitted

3.1 Rotating Machines of 100 kW and Over

For rotating machines of 100 kW and over intended for essential services (primary and secondary) or for
services related to additional optional notations requested for the unit, drawings showing the following
particulars are to be submitted for review:

i) General arrangement and assembly details

ii) Bill of materials
iii) Seating arrangements
iv) Terminal arrangements
v) Shafts
vi) Coupling
vii) Coupling bolts
viii) Stator and rotor details together with data of complete rating
ix) Details of exciter
x) Torsional vibration calculations for AC Generators with power rating equal to or above 100 KW
xi) Limits of vibration amplitudes per an internationally recognized standard
xii) Class of insulation
xiii) Designed ambient temperature and temperature rise
xiv) Degree of protection for enclosures
xv) Weights and speeds of rotating parts
xvi) Type test procedures per 6-1-7/Table 2
xvii) Type test results, as applicable, per 6-1-7/Table 2

Plans to be submitted for generator prime movers are given in 4-2-4/1.5, 4-2-1/1.5 and Appendix 4-2-1-A1
of the Marine Vessel Rules, as applicable. See also 8-2-1/5 of these Rules.

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Section 7 Electrical Systems and Control Equipment 6-1-7

3.3 Switchboards, Distribution Boards, Controllers, etc.

For switchboards, distribution boards, battery charger units, uninterruptible power system (UPS) units,
motor control centers, and motor controllers intended for essential services (primary and secondary) or for
services related to additional optional notations requested for the unit, drawings showing arrangements and
details, front view, and installation arrangements are to be submitted for review together with data for
protective device rating and setting, type of internal wiring, and size and rated current carrying capacity
(together with short-circuit current data) of bus bars and internal wiring for power circuit. In addition, a
schematic or logic diagram with a written description giving the sequence of events and system operating
procedures for electrical power supply management on switchboards, and sequential or automatic
changeover of the motors are also to be submitted for review. For equipment intended solely for drilling
operations, see 8-2-1/5, 8-2-1/7 and 8-2-1/9.

3.5 Semiconductor Converters for Adjustable Speed Motor Drives

For semiconductor converters that are used to control motor drives having a rated power of 100 kW (135
hp) and over intended for essential services (see definition in 4-1-1/3.5) or for services indicated in 4-1-1/
Table 3 and 4-1-1/Table 4, plans showing the following particulars are to be submitted:

● Front view, degree of protection for enclosure

● Schematic diagram
● Current rating of running protection of motor
● Type and size of internal wiring, and
● Cooling arrangement.

5 Rotating Machines

5.1 General
5.1.1 Applications
All rotating electrical machines of 100 kW and over intended for essential services (see 4-1-1/3.5)
or for services related to additional optional notations requested for the unit, are to be designed,
constructed and tested in accordance with the requirements of 6-1-7/5 and 6-1-7/19.

Furthermore, their design and construction are to withstand all loads (e.g., mechanical, electrical,
thermal, cyclic, etc.) that are imposed during the intended operation.

For squirrel cage electric motors serving essential services, special attention is also to be given to
the method of attachment of the rotor bars to the rotor so that the overall operational integrity of
the motor are not affected during service. The common arrangement is with the shorting ring in
full contact, via brazing or welding, with the ends of the rotor bars. A less common arrangement is
with the shorting ring only in partial contact with the ends of the rotor bars. For these less
common arrangements, calculations, analyses, tests and/or operational service history data are to
be provided, substantiating the design and construction of the rotating machine for its intended
application and service.

All other rotating electrical machines are to be designed, constructed and tested in accordance
with established industrial practices and manufacturer’s specifications. Manufacturer’s tests for
rotating electric machines less than 100 kW for essential services or for services related to
additional optional notations requested for the unit, are to include at least the tests described in
6-1-7/19.23 TABLE 2 (item 2 through item 10 and item 12), regardless of the standard of
construction. The test certificates are to be made available when requested by the Surveyor.
Acceptance of machines is to be based on satisfactory performance test after installation. For
rotating machines intended solely for drilling operations, see 8-2-1/5. Electric motors intended for

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Chapter 1 Material, Marine Equipment and Machinery Certification
Section 7 Electrical Systems and Control Equipment 6-1-7

installation into jacking gear systems are to meet the requirements of 6-1-9/15.1 and 6-1-9/25.5.5
TABLE 2.

5.1.2 Certification on Basis of an Approved Quality Assurance Program

See 6-1-1/9.

5.1.3 References
5.1.3(a) Angles of Inclination.
For the requirements covering angles of inclination for design condition, see 6-1-1/3.5 and
4-1-1/7.1 TABLE 1.

5.1.3(b) Insulation Material.

For the requirements covering insulation material, see 6-1-7/1.3.

5.1.3(c) Capacity of Generators.

For requirements covering main generator capacity, see 4-3-2/3.1.2 and 4-3-2/3.5. For
requirements covering emergency generator capacity, see 4-3-2/5.3.

5.1.3(d) Power Supply by Generators.

For requirements covering power supply by main or emergency generator, see 4-3-2/3.1 and
4-3-2/5.5.2, respectively.

5.1.3(e) Protection for Generator Circuits.

For requirements covering protection for generator, see 4-3-2/9.3, 4-3-2/9.5 and 4-3-2/9.7.

5.1.3(f) Protection for Motor Circuits.

For requirements covering protection for motor branch circuit, see 4-3-2/9.13.

5.1.3(g) Installation.
For requirements covering installation, see 4-3-3/3.3 for generators and 4-3-3/3.5 for motors.

5.1.3(h) Protection Enclosures and its Selection.

For requirements covering degree of the protection and the selection of equipment, see 4-3-1/15
and 4-3-3/3.1, respectively.

5.3 Insulation Resistance Measurement

The resistance is to be measured before the commencement of the testing and after completion of the
testing for all circuits. Circuits or groups of circuits of different voltages above earth are to be tested
separately. This test is to be made with at least 500 volts DC, and the insulation resistance in megohms of
the circuits while at their operating temperatures is to be normally at least equal to:
Rated Voltage of the Machine
(Rating in kVA/100) + 1000

The minimum insulation resistance of the fields of machines separately excited with voltage less than the
rated voltage of the machine is to be of the order of one-half to one megohm.

5.5 Overload and Overcurrent Capability

5.5.1 AC Generators
AC generators are to be capable of withstanding a current equal to 1.5 times the rated current for
not less than 30 seconds. The test may be performed in conjunction with the short circuit testing,
provided the electrical input energy to the machine is not less than that required for the above
overload capability.

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5.5.2 AC Motors
5.5.2(a) Overcurrent Capacity.
Three-phase motors, except for commutator motors, having rated outputs not exceeding 315 kW
and rated voltages not exceeding 1 kV are to be capable of withstanding a current equal to 1.5
times the rated current for not less than two minutes. For three-phase and single phase motors
having rated outputs above 315 kW, the overcurrent capacity is to be in accordance with the
manufacturer’s specification. The test may be performed at a reduced speed.

5.5.2(b) Overload Capacity.

Three-phase induction motors are to be capable of withstanding for 15 seconds, without stalling or
abrupt change in speed, an excess torque of 60% of their rated torque, the voltage and frequency
being maintained at their rated values.

5.5.2(c) Overload Capacity for Synchronous Motors.

Three-phase synchronous motors are to be capable of withstanding an excess torque, as specified
below, for 15 seconds without falling out of synchronism, the excitation being maintained at the
value corresponding to the rated load.

Synchronous (wound rotor) induction motors: 35% excess torque

Synchronous (cylindrical rotor) motors: 35% excess torque
Synchronous (salient pole) motors: 50% excess torque

When automatic excitation is used, the limit of torque values is to be the same as with the
excitation equipment operating under normal conditions.

5.7 Dielectric Strength of Insulation

5.7.1 Application
The dielectric test voltage is to be successively applied between each electric circuit and all other
electric circuits and metal parts earthed and for direct-current (DC) rotating machines between
brush rings of opposite polarity. Interconnected polyphase windings are to be considered as one
circuit. All windings, except that under test, are to be connected to earth.

5.7.2 Standard Voltage Test

The insulation of all rotating machines is to be tested with the parts completely assembled and not
with the individual parts. The dielectric strength of the insulation is to be tested by the continuous
application for 60 seconds of an alternating voltage having a frequency of 25 to 60 Hz and voltage
in 6-1-7/19.23 TABLE 1. The requirements in 6-1-7/19.23 TABLE 3 apply to those machines
other than high voltage systems covered by 6-1-7/19.19.

5.7.3 Direct Current Test

A standard voltage test using a direct current source equal to 1.7 times the required alternating-
current voltage is acceptable.

5.9 Temperature Ratings

5.9.1 Temperature Rises
5.9.1(a) Continuous Duty Machines.
After the machine has been run continuously under a rated load until steady temperature condition
has been reached, the temperature rises are not to exceed those given in 6-1-7/19.23 TABLE 4.

5.9.1(b) Short-time Duty Machines.

After the machine has been run at a rated load during the rated time, followed by a rest and de-
energized period of sufficient duration to re-establish the machine temperatures within 2°C (3.6°F)

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of the coolant, the temperature rises are not to exceed those given in 6-1-7/19.23 TABLE 4. At the
beginning of the temperature measurement, the temperature of the machine is to be within 5°C
(8°F) of the temperature of the coolant.

5.9.1(c) Periodic Duty Machines.

The machine has been run at a rated load for the designed load cycle to be applied and continued
until obtaining the practically identical temperature cycle. At the middle of the period causing the
greatest heating in the last cycle of the operation, the temperature rises are not to exceed those
given in 6-1-7/19.23 TABLE 4.

5.9.1(d) Non-periodic Duty Machines.

After the machine has been run continuously or intermittently under the designed variations of the
load and speed within the permissible operating range until reaching the steady temperature
condition, the temperature rises are not to exceed those given in 6-1-7/19.23 TABLE 4.

5.9.1(e) Insulation Material Above 180°C (356°F).

Temperature rises for insulation materials above 180°C (356°F) are to be defined during the
approval process of these materials in accordance with 6-1-7/1.3.6.

5.9.2 Ambient Temperature

These final temperatures are based on an ambient temperature of 50°C (122°F), for machines
located within boiler and engine rooms in accordance with 4-3-1/17. Where provision is made for
ensuring the ambient temperature of the space being maintained at 40°C (104°F) or less, as by air
cooling or by locating the machine outside of the boiler and engine rooms, the temperature rises of
the windings may be 5°C (9°F) higher. The ambient temperature is to be taken in at least two
places within 1.83 m (6 ft) of the machine under test and by thermometers having their bulbs
immersed in oil contained in an open cup.

5.11 Construction and Assembly

5.11.1 Enclosure, Frame and Pedestals
Magnet frames and pedestals may be separate but are to be secured to a common foundation.

5.11.2 Shafts and Couplings

Rotating shaft, hollow shaft and coupling flange with bolts are to comply with 4-2-4/5.3, 4-3-2/5.3
and 4-3-5/5.7.3 of the Marine Vessel Rules. Plans to be submitted are given in 4-2-4/1.5 and
4-2-1/1.9 of the Marine Vessel Rules.

5.11.3 Circulating Currents

Means are to be provided to prevent circulating currents from passing between the journals and
the bearings where the design and arrangement of the machine is such that damaging current is
expected. Where such protection is required, a warning plate is to be provided in a visible place
cautioning against the removal of such protection.

5.11.4 Rotating Exciters

Rotating exciters are to conform to all applicable requirements for generators.

5.11.5 Insulation of Windings

Armature and field coils are to be treated to resist oil and water.

5.11.6 Protection Against Cooling Water

Where water cooling is used, the cooler is to be so arranged to avoid entry of water into the
machine, whether through leakage or from condensation in the heat exchanger.

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5.11.7 Moisture-Condensation Prevention

Where steam-heating coils are installed for this purpose, there are to be no pipe joints inside of the
casings. See item 7 in 6-1-7/19.23 TABLE 8 for space heater pilot lamp for alternating-current
generators.

All generators, and each propulsion motor are to be provided with a means to prevent moisture
condensation in the machine when idle.

Motors, rated 50 kW and over, used for essential services and located in damp spaces or exposed
to weather are to be provided with a means to prevent moisture condensation in the machine when
idle.

5.11.8 Terminal Arrangements

Terminals are to be provided at an accessible position and protected against mechanical damage
and accidental contact for earthing, short-circuit or touching. Terminal leads are to be secured to
the frame and the designation of each terminal lead are to be clearly marked. The ends of terminal
leads are to be fitted with connectors. Cable glands or similar are to be provided where cable
penetrations compromise the protection property of terminal enclosures.

5.11.9 Nameplates
Nameplates of corrosion-resistant material are to be provided in an accessible position of the
machine and are to indicate at least the information as listed in 6-1-7/19.23 TABLE 5.

5.13 Lubrication
Rotating machines are to have continuous lubrication at all running speeds and all normal working bearing
temperatures, with the unit’s inclinations specified in 4-1-1/7.1. Unless otherwise approved, where forced
lubrication is employed, the machines are to be provided with means to shut down their prime movers
automatically upon failure of the lubricating system. Each self-lubricating sleeve bearing is to be fitted
with an inspection lid and means for visual indication of oil level or an oil gauge. Refer to 4-3-3/3.3 for
lubrication of generators in ship-type units.

5.15 Operating and Overspeed Governors for Generator Prime Movers

Gas turbines and diesel engines used as prime movers for main and emergency generators are to comply
with the requirements specified in 6-1-3/3.3 and 6-1-3/3.5, respectively.

5.17 Alternating-Current (AC) Generators

5.17.1 Control and Excitation of Generators
Excitation current for generators is to be provided by attached rotating exciters or by static
exciters deriving their source of power from the machine being excited.

5.17.2 Voltage Regulation

5.17.2(a) Voltage Regulators.
A separate regulator is to be supplied for each AC generator. When two or more generators are
intended to be operated in parallel, reactive-droop compensating means are to be provided to
divide the reactive power properly between the generators.

5.17.2(b) Variation from Rated Voltage - Steady Conditions.

Each AC generator for unit main service driven by its prime mover having governor
characteristics complying with 6-1-3/3.3.1 or 6-1-3/3.5.1 is to be provided with an excitation
system capable of maintaining the voltage under steady conditions within plus or minus 2.5% of
the rated voltage for all loads between zero and rated load at rated power factor. These limits can
be increased to plus or minus 3.5% for emergency sets.

5.17.2(c) Variation from rated voltage -Transient Conditions.

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Momentary voltage variations are to be within the range of minus 15% to plus 20% of the rated
voltage, and the voltage is to be restored to within plus or minus 3% of the rated voltage in not
more than 1.5 seconds when:

● A load equal to the starting current of the largest motor or a group of motors, but in any case,
at least 60% of the rated current of the generator, and power factor of 0.4 lagging or less, is
suddenly thrown on with the generator running at no load; and
● A load equal to the above is suddenly thrown off.

Subject to ABS approval, such voltage regulation during transient conditions can be calculated
values based on the previous type test records, and need not to be tested during factory testing of a
generator.

Consideration can be given to performing the test required by 6-1-7/19.23 TABLE 2, Item 4
according to precise information concerning the maximum values of the sudden loads instead of
the values indicated above, provided precise information is available. The precise information
concerning the maximum values of the sudden loads is to be based on the power management
system arrangements and starting arrangements provided for the electrical system.

5.17.2(d) Short Circuit Conditions.

Under steady-state short-circuit conditions, the generator together with its excitation system is to
be capable of maintaining a steady-state short-circuit current of not less than three times its rated
full load current for a period of two seconds or of such magnitude and duration as required to
properly actuate the associated electrical protective devices. In order to provide sufficient
information for determining the discrimination settings in the distribution system where the
generator is going to be used, the generator manufacturer is to provide documentation showing the
transient behavior of the short circuit current upon a sudden short-circuit occurring when excited,
and running at nominal speed. The influence of the automatic voltage regulator is to be taken into
account, and the setting parameters for the voltage regulator are to be noted together with the
decrement curve. Such a decrement curve is to be available when the setting of the distribution
system’s short-circuit protection is calculated. The decrement curve need not be based on physical
testing. The manufacturer’s simulation model for the generator and the voltage regulator can be
used where this has been validated through the previous type test on the same model.

5.17.3 Parallel Operation

For AC generating sets operating in parallel, the following requirements are to be complied with.
See also 4-3-2/9.5.2 for protection of AC generators in parallel operation.

5.17.3(a) Reactive Load Sharing.

The reactive loads of the individual generating sets are not to differ from their proportionate share
of the combined reactive load by more than 10% of the rated reactive output of the largest
generator, or 25% of the rated reactive output of the smallest generator, whichever is the less.

5.17.3(b) Load Sharing.

For any load between 20% and 100% of the sum of the rated output (aggregate output) of all
generators, the load on any generator is not to differ more than 15% of the rated output in kilowatt
of the largest generator or 25% of the rated output in kilowatt of the individual generator in
question, whichever is the less, from its proportionate share of the combined load for any steady
state condition. The starting point for the determination of the foregoing load-distribution
requirements is to be at 75% of the aggregate output with each generator carrying its proportionate
share.

5.17.3(c) Facilities for Load Adjustment.

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Facilities are to be provided to adjust the governor sufficiently fine to permit an adjustment of load
not exceeding 5% of the aggregate output at normal frequency.

5.19 Direct-Current (DC) Generators

5.19.1 Control and Excitation of Generators
5.19.1(a) Field Regulations.
Means are to be provided at the switchboard to enable the voltage of each generator to be adjusted
separately. This equipment is to be capable of adjusting the voltage of the DC generator to within
0.5% of the rated voltage at all loads between no-load and full-load.

5.19.1(b) Polarity of Series Windings.

The series windings of each generator for two wire DC system are to be connected to the negative
terminal of each machine.

5.19.1(c) Equalizer Connections.

See 6-1-7/9.13.3.

5.19.2 Voltage Regulation

5.19.2(a) Shunt or Stabilized Shunt-wound Generator.
When the voltage has been set at full-load to its rated value, the removal of the load is not to cause
a permanent increase of the voltage greater than 15% of the rated voltage. When the voltage has
been set either at full-load or at no-load, the voltage obtained at any value of the load is not to
exceed the no-load voltage.

5.19.2(b) Compound-wound Generator.

Compound-wound generators are to be so designed in relation to the governing characteristics of
prime mover that with the generator at full-load operating temperature and starting at 20% load
with voltage within 1% of rated voltage, it gives at full-load a voltage within 1.5% of rated
voltage. The average of ascending and descending voltage regulation curves between 20% load
and full-load is not to vary more than 3% from rated voltage.

5.19.2(c) Automatic Voltage Regulators.

Unit main service generators which are of the shunt type are to be provided with automatic voltage
regulators. However, if the load fluctuation does not interfere with the operation of essential
auxiliaries, shunt-wound generators without voltage regulators or stabilized shunt-wound
machines may be used. An automatic voltage regulator is not required for the unit main service
generators of approximately flat-compounded type. Automatic voltage regulators are to be
provided for all service generators driven by variable speed engines used also for propulsion
purposes, whether these generators are of the shunt, stabilized shunt or compound-wound type.

5.19.3 Parallel Operation

For DC generating sets operating in parallel, the following requirements are to be complied with.
See also 4-3-2/9.7.2 for protection of DC generators in parallel operation.

5.19.3(a) Stability.
The generating sets are to be stable in operation at all loads from no-load to full-load.

5.19.3(b) Load Sharing.

For any load between 20% and 100% of the sum of the rated output (aggregate output) of all
generators, the load on any generator is not to differ more than 12% of the rated output in kilowatt
of the largest generator or 25% of the rated output in kilowatt of the individual generator in
question, whichever is the less, from its proportionate share of the combined load for any steady
state condition. The starting point for the determination of the foregoing load-distribution

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requirements is to be at 75% of the aggregate output with each generator carrying its proportionate
share.

5.19.3(c) Tripping of Circuit Breaker.

DC generators which operate in parallel are to be provided with a switch which trips the generator
circuit breaker upon functioning of the overspeed device.

5.21 AC Generating Sets

5.21.1 General
Notwithstanding the requirements in 6-1-7/5, the provisions of this Subsection are applicable to
AC generating sets driven by reciprocating internal combustion engines irrespective of their types
(i.e., diesel engine, dual fuel engine, gas-fuel engine), except for those sets consisting of a
propulsion engine which also drives power take off (PTO) generator(s).

5.21.2 Torsional Vibration Levels

The generating set is to show torsional vibration levels which are compatible with the allowable
limits for the alternator, shafts, coupling and damper. The coupling selection for the generating set
is to take into account the stresses and torques imposed on it by the torsional vibration of the
system.

Torsional vibration calculations are to be submitted to ABS for approval when the engine rated
power is 110 kW or above.

5.21.3 Rated Power

The rated power is to be determined in accordance with the actual use of the generator set.

5.21.4 Rating Plate

The alternator manufacturer or the entity responsible for assembling the generating set is to install
a rating plate marked with at least the following information:

i) Generating set manufacturer’s name or mark

ii) Set serial number
iii) Set date of manufacture (month/year)
iv) Rated power (both in kW and KVA) with one of the prefixes COP, PRP (or, only for
emergency generating sets, LTP) as defined in ISO 8528-1
v) Rated power factor
vi) Set rated frequency (Hz)
vii) Set rated voltage (V)
viii) Set rated current (A)
ix) Mass (kg)

7 Accumulator Batteries

7.1 General
7.1.1 Application
All accumulator batteries for engine starting, essential or emergency services are to be constructed
and installed in accordance with the following requirements. Accumulator batteries for services
other than the above are to be constructed and equipped in accordance with good commercial

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practice. All accumulator batteries are subject to a satisfactory performance test conducted after
installation to the satisfaction of the Surveyor.

7.1.2 Sealed Type Batteries

Where arrangements are made for releasing gas through a relief valve following an overcharge
condition, calculations demonstrating compliance with the criteria in 4-3-3/3.7.3 under the
expected rate of hydrogen generation are to be submitted together with the details of installation
and mechanical ventilation arrangements.

7.3 Construction and Assembly

7.3.1 Cells and Filling Plugs
The cells are to be constructed to prevent spilling of electrolyte due to an inclination of 40 degrees
from normal. The filling plugs are to be so constructed as to prevent spilling of electrolyte due to
the unit’s movements, such as rolling and pitching.

7.3.2 Crates and Trays

The cells are to be grouped in crates or trays of rigid construction equipped with handles to
facilitate handling. For protection from corrosion, see 4-3-3/3.7.4. The mass of crates or trays are
not to exceed 100 kg (220.5 lb).

7.3.3 Nameplate
Name plates of corrosion-resistant material are to be provided in an accessible position of each
crate or tray and are to indicate at least the information as listed in 6-1-7/19.23 TABLE 5.

9 Switchboards, Distribution Boards, Controllers, etc.

9.1 General
9.1.1 Applications
Switchboards are to provide adequate control of the generation and distribution of electric power.
The following equipment are to be constructed and tested in accordance with the following
requirements to the satisfaction of the Surveyor.

9.1.1(a) Switchboards.
Switchboards for essential services or for services related to additional optional notations
requested for the unit.

9.1.1(b) Motor Controllers.

Motor Controllers of 100 kW and over intended for essential services or for services related to
additional optional notations requested for the drilling unit.

9.1.1(c) Motor Control Centers.

Motor control centers with aggregate loads of 100 kW or more intended for essential services or
for services related to additional optional notations requested for the unit.

9.1.1(d) Battery Charger Units and Uninterruptible Power System (UPS) Units.
Battery charger units of 25 kW and over and uninterruptible power system (UPS) units of 50 kVA
and over intended for essential services, services related to additional optional notations requested
for the unit, emergency source of power or transitional source of power.

9.1.1(e) Distribution Boards.

Distribution boards associated with the charging or discharging of the battery system or
uninterruptible power system (UPS) in 6-1-7/9.1.1(d).

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Switchboard, distribution board, battery charger units, uninterruptible power system (UPS) units,
motor control centers and motor controllers not covered by the above paragraph are to be
constructed and equipped in accordance with good commercial practice, and are subject to a
satisfactory performance test conducted after installation to the satisfaction of the Surveyor.

9.1.2 References
9.1.2(a) Angles of Inclination.
For the requirements covering angles of inclination for design condition, see 6-1-1/3.5 and
4-1-1/7.1 TABLE 1.

9.1.2(b) Emergency Switchboard.

For requirements covering emergency switchboard, see 4-3-2/5.9.

9.1.2(c) Circuit Breakers.

For requirements covering generator circuit breakers, see 6-1-7/13.1.

9.1.2(d) Feeder Protection.

For requirements covering feeder protection, see 4-3-2/9.3 to 4-3-2/9.17, 4-3-2/11.3, 4-3-2/13.1.4
and 4-3-2/13.3.3.

9.1.2(e) Hull Return and Earthed Distribution System.

For requirements covering hull return system and earthed distribution system, see 4-3-2/7.3 and
4-3-2/7.5, respectively.

9.1.2(f) Earthing.
For requirements covering earthing connections, see 4-3-3/7. For requirements covering earthing
for main and emergency switchboards of three-wire dual-voltage DC systems, see 4-3-5/5.3.

9.1.2(g) Installation.
For requirements covering installation, see 4-3-3/3.9 for switchboard, 4-3-3/3.11 for distribution
boards, and 4-3-3/3.13 for motor controllers and control centers.

9.1.2(h) Protection Enclosures and its Selection.

For requirements covering degree of the protection and the selection of equipment, see 4-3-1/15
and 4-3-3/3.1, respectively.

9.3 Insulation Resistance Measurement

The insulation resistance between current-carrying parts (connected together for the purpose of this test)
and earth and between current-carrying parts of opposite polarity is to be measured at a DC voltage of not
less than 500 volts before and after the dielectric strength tests. The insulation resistance measurement
after the dielectric strength tests is to be carried out before components which have been disconnected for
the dielectric tests are reconnected, and the insulation resistance is not to be less than 1 megohm.

9.5 Dielectric Strength of Insulation

The dielectric strength of the insulation is to be tested for 60 seconds by an alternating voltage applied in
accordance with 6-1-7/19.23 TABLE 6 between:

i) All live parts and the interconnected exposed conductive parts, and
ii) Each phase and all other phases connected for this test to the interconnected exposed conductive
parts of the unit.

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The test voltage at the moment of application is not to exceed 50% of the values given in 6-1-7/19.23
TABLE 6. It is to be increased steadily within a few seconds to the required test voltage and maintained for
60 seconds. Test voltage is to have a sinusoidal waveform and a frequency between 45 Hz and 60 Hz.

9.5.1 Production-line Apparatus

Standard apparatus produced in large quantities for which the standard test voltage is 2500 volts or
less can be tested for one second with a test voltage 20% higher than the one-minute test voltage.

9.5.2 Devices with Low Insulation Strength

Certain devices such as potential transformers having inherently lower insulation strength are to
be disconnected during the test.

9.7 Construction and Assembly

9.7.1 Enclosures and Assemblies
Enclosures and assemblies are to be constructed of steel or other suitable, incombustible,
moisture-resistant materials and reinforced as necessary to withstand the mechanical, electrical
(magnetic) and thermal stresses likely to be encountered in service, and are to be protected against
corrosion. No wood is to be used, except for hardwood for nonconducting hand rails. Insulating
materials are to be flame-retardant and moisture-resistant. The supporting framework is to be of
rigid construction.

9.7.2 Dead Front

The dead-front type is to be used. Live-front type is not acceptable, regardless of the voltage
ratings.

9.7.3 Mechanical Strength

All levers, handles, hand wheels, interlocks and their connecting links, shafts and bearings for the
operation of switches and contactors are to be of such proportions that they are not broken or
distorted by manual operation.

9.7.4 Mechanical Protection

The sides and the rear and, where necessary, the front of switchboards are to be suitably guarded.
Exposed live parts having voltages to earth exceeding a voltage of 55 volts DC or 55 volts AC rms
between conductors are not to be installed on the front of such switchboards. Unless the
switchboard is installed on an electrically insulated floor, non-conducting mats or gratings are to
be provided at the front and rear of the switchboard. Where the floor on which the switchboard is
installed is of electrically insulated construction, the insulation level of the floor to the earth is to
be at least 50 MΩ. A notice plate is to be posted at the entrance to the switchboard room or on the
switchboard front panel to state that the floor in the room is of electrically insulated construction.
Drip covers are to be provided over switchboards when subject to damage by leaks or falling
objects.

9.9 Bus Bars, Wiring and Contacts

9.9.1 Design
Copper bar is to be used for main and generator bus in the switchboard. Other materials and
combination of materials are subject to ABS technical assessment and approval. Generator bus
bars are to be designed on a basis of maximum generator rating. All other bus bars and bus-bar
connections are to be designed for at least 75% of the combined full-load rated currents of all
apparatus they supply, except that when they supply one unit or any group of units in continuous
operation, they are to be designed for full load.

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9.9.2 Operating Temperature of Bus Bars

Bus bars are to be proportioned to avoid temperatures which affect the normal operation of
electrical devices mounted on the board.

9.9.3 Short Circuit Rating

Circuit breakers and bus bars are to be mounted, braced and located so as to withstand the thermal
effects and mechanical forces resulting from the maximum prospective short circuit current.
Switchboard instruments, controls, etc., are to be located with respect to circuit breakers to
minimize the thermal effects due to short circuit currents.

9.9.4 Internal Wiring

Instrument and control wiring is to be of the stranded type and is to have heat-resisting and flame-
retarding insulation. Wiring from hinged panels is to be of the extra-flexible type.

9.9.5 Arrangement
9.9.5(a) Accessibility.
The arrangement of bus bars and wiring on the back is to be such that all lugs are readily
accessible.

9.9.5(b) Locking of Connections.

All nuts and connections are to be fitted with locking devices to prevent loosening due to
vibration. Bolted bus bar connections are to be suitably treated (e.g., silver plating) to avoid
deterioration of electrical conductivity over time.

9.9.5(c) Soldered Connections.

Soldered connections are not to be used for connecting or terminating any wire or cable of
nominal cross-sectional area of greater than 2.5 mm2 (4,933 circ. mils). Soldered connections,
where used, are to have a solder contact length at least 1.5 times the diameter of the conductor.

9.9.6 Clearances and Creepage Distances

9.9.6(a) General.
For bare busbars, the minimum clearances and creepage distances between live parts of different
potential (i.e., between phases and between phase and the ground) are to be in accordance with
6-1-7/19.23 TABLE 7.

9.9.6(b) Alternative.
Alternatively, reduced creepage and clearance distances may be used provided:

i) The equipment is not installed in ‘Machinery Spaces of Category A’ or in areas affected

by a Local Fixed Pressure Water-spraying or Local Water-mist Fire Extinguishing
System.
ii) The minimum clearance distance is not to be less than 8 mm
iii) The minimum creepage distance is not to be less than 16 mm.
iv) The equipment complies with IEC 61439-1 and 61439-2
v) In applying IEC 61439-1 and 61439-2, the equipment is considered to be:

● Of overvoltage Category III,

● Installed in an environment of pollution degree 3,
● Having insulating material of type IIIa, and
● Installed in inhomogeneous field conditions

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vi) The temperature dependent criteria in IEC 61439-1 and 61439-2 are derated to meet the
ambient temperatures found on marine installations. Refer to 4-1-1/7.7 TABLE 2.
vii) The equipment is subject to an impulse voltage test with test voltage values shown in the
Table below. Where intermediate values of rated operational voltage are used, the next
higher rated impulse withstand test voltage is to be used. The impulse voltage test reports
are to be submitted to ABS for review.
Rated Operational Voltage Rated Impulse Withstand Test Voltage
V kV

50 0.8

100 1.5

150 2.5

300 4

600 6

1000 8

9.9.7 Terminals
Terminals or terminal rows for systems of different voltages are to be clearly separated from each
other. The rated voltage is to be clearly indicated at least once for each group of terminals which
have been separated from the terminals with other voltage ratings. Terminals with different
voltage ratings, each not exceeding 50 V DC or 50 V AC may be grouped together. Each terminal
is to have a nameplate indicating the circuit designation.

9.11 Control and Protective Devices

9.11.1 Circuit-disconnecting Devices
9.11.1(a) Systems Exceeding 50 Volts.
Distribution boards, chargers or controllers for distribution to motors, appliances, and lighting or
other branch circuits are to be fitted with multipole circuit breakers or a multipole switch-fuse
combination in each unearthed conductor.

9.11.1(b) Systems of 50 Volts and Less.

For distribution boards, chargers or controllers where voltage to earth or between poles does not
exceed 50 volts DC or 50 volts AC rms, the fuses can be provided without switches.

9.11.1(c) Disconnect Device.

The rating of the disconnecting device is to be coordinated with the voltage and current
requirements of the load. The disconnect device is to indicate by position of the handle, or
otherwise, whether it is open or closed.

9.11.2 Arrangement of Equipment

9.11.2(a) Air Circuit Breakers.
Air circuit breaker contacts are to be kept at least 305 mm (12 in.) from the unit’s structure unless
insulation barriers are installed.

9.11.2(b) Voltage Regulators.

Voltage regulator elements are to be provided with enclosing cases to protect them from damage.

9.11.2(c) Equipment Operated in High Temperature.

Where rheostats or other devices that can operate at high temperatures are mounted on the
switchboard, they are to be naturally ventilated and so located or isolated by barriers as to prevent

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excessive temperature of adjacent devices. When this cannot be accomplished, the rheostat or
other device is to be mounted separately from the switchboard.

9.11.2(d) Accessibility to Fuses.

All fuses, except for instrument and control circuits, are to be mounted on or be accessible from
the front of the switchboard.

9.11.2(e) Protective Device for Instrumentation.

All wiring on the boards for instrumentation is to be protected by fuses or current limiting devices.
See 4-3-2/9.17.

9.11.2(f) Wearing Parts.

All wearing parts are to be accessible for inspection and readily renewable.

9.11.3 Markings
Identification plates are to be provided for each piece of apparatus to indicate clearly its service.
Identification plates for feeders and branch circuits are to include the circuit designation and the
rating of the fuse or circuit-breaker trip setting required by the circuit.

9.13 Switchboards
In addition to 6-1-7/9.1 to 6-1-7/9.11, as applicable, the switchboards for essential or emergency services
are to comply with the following requirements.

9.13.1 Handrails
Insulated handrail or insulated handles are to be provided on the front of the switchboard.
Similarly, where access to the rear is required, insulated handrail or insulated handles are also to
be fitted on the rear of the switchboard.

9.13.2 Main Bus Bar Subdivision

Where the main source of electrical power is necessary for propulsion of the unit, the main bus bar
is to be subdivided into at least two sections which are to be normally connected by circuit breaker
or other approved means. As far as practicable, the connection of generating sets and any other
duplicated equipment is to be equally divided between the sections.

If the arrangement is such that the main switchboard is divided into separate sections which are
interconnected by cable, the cable is to be protected at each end against faults.

9.13.3 Equalizer Circuit for Direct-current (DC) Generators

9.13.3(a) Equalizer Main Circuit.
The current rating of the equalizer main circuit for direct-current (DC) generators is not to be less
than half of the rated full-load current of the generator.

9.13.3(b) Equalizer Bus Bars.

The current rating of the equalizer bus bars is not to be less than half of the rated full-load current
of the largest generator in the group.

9.13.4 Equipment and Instrumentation

Equipment and instrumentation are to be provided in accordance with 6-1-7/19.23 TABLE 8. They
are to be suitable for starting, stopping, synchronizing and paralleling each generator set from the
main switchboard. They can be mounted on the centralized control console, if the main
switchboard is located in the centralized control station.

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9.15 Motor Controllers and Control Centers

In addition to 6-1-7/9.1 to 6-1-7/9.11 as applicable, the motor controllers and control centers for essential
or emergency services are to comply with the following requirements.

9.15.1 Enclosures and Assemblies

The following materials are acceptable for the enclosures.

● Cast metal, other than die-cast metal, at least 3 mm (1/8 in.) thick at every point.
● Nonmetallic materials which have ample strength, are noncombustible and nonabsorptive,
(e.g., laminated phenolic material).
● Sheet metal of adequate strength.

Motor control centers are to be constructed so that they are secured to a solid foundation, be self-
supported or be braced to the bulkhead.

9.15.2 Disconnect Switches and Circuit Breakers

Means are to be provided for the disconnection of the full load from all live poles of supply of
every motor at 0.5 kW or above and its controlgear. Where the controlgear is mounted on or
adjacent to a main or auxiliary distribution switchboard, a disconnecting switch in the switchboard
can be used for this purpose. Otherwise, a disconnecting switch within the controlgear enclosure
or a separate enclosed disconnecting switch is to be provided. Disconnect switches and circuit
breakers are to be operated without opening the enclosures in which they are installed.

9.15.3 Auto-starters
Alternating-current (AC) motor manual auto-starters with self-contained auto-transformers are to
be provided with switches of the quick-make-and-break type, and the starter is to be arranged so
that it is impossible to throw to the running position without having first thrown to the starting
position. Switches are to be preferably of the contactor or air-break-type.

9.17 Battery Systems and Uninterruptible Power Systems (UPS)

In addition to 6-1-7/9.1 to 6-1-7/9.11, as applicable, equipment for essential, emergency, and transitional
sources of power services are to comply with the following requirements. Such equipment include:

● Battery charging and discharging units of 25 kW and over and the associated distribution boards.
● Uninterruptible power supply (UPS) units of 50 kVA and over and the associated distribution boards.
9.17.1 Definitions
Uninterruptible Power System (UPS) - A combination of converters, switches and energy storage
means, for example batteries, constituting a power system for maintaining continuity of load
power in case of input power failure.

Off-line UPS unit - A UPS unit where under normal operation the output load is powered from the
bypass line (raw mains) and only transferred to the inverter if the bypass supply fails or goes
outside preset limits. This transition invariably results in a brief (typically 2 to 10 ms) break in the
load supply.

Line interactive UPS unit - An off-line UPS unit where the bypass line switch to stored energy
power when the input power goes outside the preset voltage and frequency limits.

On-line UPS unit - A UPS unit where under normal operation the output load is powered from the
inverter, and therefore continues to operate without break in the event of the supply input failing
or going outside preset limits.

DC UPS unit - A UPS unit where the output is in DC (direct current).

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9.17.2 Battery Charging Rate

Except when a different charging rate is necessary and is specified for a particular application, the
charging facilities are to be such that the completely discharged battery can be recharged to 80%
capacity in not more than 10 hours. See also 4-3-4/3.7.3.

9.17.3 Discharge Protection

An acceptable means, such as reverse current protection, is to be provided for preventing a failed
component in the battery charger unit or uninterruptible power system (UPS) unit from
discharging the battery.

9.17.4 Design and Construction

9.17.4(a) Construction.
Battery charger units and uninterruptible power system (UPS) units are to be constructed in
accordance with the IEC 62040 Series, or an acceptable and relevant national or international
standard.

9.17.4(b) Operation.
The operation of the UPS is not to depend upon external services.

9.17.4(c) Type.
The type of UPS unit employed, whether off-line, line interactive or on-line, is to be appropriate to
the power supply requirements of the connected load equipment.

9.17.4(d) Continuity of Supply

An external bypass is to be provided to account for a failure within the uninterruptible power
system (UPS). For battery charger units and DC UPS units, see 4-3-2/7.1.6(c). A UPS with an
integral Maintenance Bypass Switch allowing for battery replacement or repair of the inverter
converter is acceptable as an alternative to an external bypass.

9.17.4(e) Monitoring and Alarming.

The battery charger unit or uninterruptible power system (UPS) unit is to be monitored and
audible and visual alarm is to be given in a normally attended location for the following:

● Power supply failure (voltage and frequency) to the connected load;

● Earth fault,
● Operation of battery protective device,
● When the battery is being discharged, and
● When the bypass is in operation for on-line UPS units. When changeover occurs, for battery
charger units and DC UPS units required to comply with 4-3-2/7.1.6(c).

11 Transformers

11.1 General
11.1.1 Applications
All transformers which serve for essential or emergency electrical supply are to be constructed,
tested, and installed in accordance with the following requirements. Transformers other than the
above services, auto-transformers for starting motors or isolation transformers are to be
constructed and equipped in accordance with good commercial practice. All transformers are to be
of the dry and air cooled type. The use of liquid immersed type transformers is subject to ABS
technical assessment and approval .Transformers other than for essential or emergency services
are subject to a satisfactory performance test conducted after installation to the satisfaction of the
Surveyor.

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11.1.2 References
11.1.2(a) Power Supply Arrangement.
For requirements covering arrangement of power supply through transformers to unit main service
systems, see 4-3-2/7.1.6.

11.1.2(b) Protection.
For requirements covering protection of transformers, see 4-3-2/9.15.

11.1.2(c) Protection Enclosures and its Selection.

For requirements covering selection of the protection enclosures for location conditions, see
4-3-3/3.1.1.

11.1.3 Forced Cooling Arrangement (Air or Liquid)

Where forced cooling medium is used to preclude the transformer from exceeding temperatures
outside of its rated range, monitoring and alarm means are to be provided and arranged so that an
alarm activates when pre-set temperature conditions are exceeded. Manual or automatic
arrangements are to be made to reduce the transformer load to a level corresponding to the cooling
available.

11.1.4 Rating
Transformers are to be continuously rated based on the maximum expected ambient temperature
to which they are subjected, but not less than 45°C (113°F). Temperature rises in accordance with
alternative transformer construction standards is also to be considered. Also, refer to 4-3-1/17.1
for electrical equipment installed spaces considered to have lower ambient temperatures and in
environmentally controlled spaces.

11.3 Temperature Rise

The maximum temperature rise of the transformer insulated windings, based on an ambient temperature of
45°C (113°F), is not to exceed that in 6-1-7/19.23 TABLE 9.

11.5 Construction and Assembly

11.5.1 Windings
All transformer windings are to be treated to resist moisture, sea atmosphere and oil vapors.

11.5.2 Terminals
Terminals are to be provided in an accessible position. The circuit designation is to be clearly
marked on each terminal connection. The terminals are to be so spaced or shielded that they
cannot be accidentally earthed, short-circuited or touched.

11.5.3 Nameplate
Nameplates of corrosion-resistant material are to be provided in an accessible position of the
transformer and are to indicate at least the information as listed in 6-1-7/19.23 TABLE 5.

11.5.4 Prevention of the Accumulation of Moisture

Transformers of 10 kVA/phase and over are to be provided with effective means to prevent
accumulation of moisture and condensation within the transformer enclosure where the
transformer is disconnected from the switchboard during standby (cold standby). Where it is
arranged that the transformer is retained in an energized condition throughout a period of standby
(hot standby), the exciting current to the primary winding may be considered as a means to meet
the above purpose. In case of hot standby, a warning plate is to be posted at or near the
disconnecting device for the primary side feeder to the transformer.

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12 Semiconductor Converters for Adjustable Speed Motor Drives

12.1 Application
All semiconductor converters that are used to control motor drives having a rated power of 100 kW (135
hp) and over intended for essential services (see definition in 4-1-1/3.5) or for services indicated in
4-8-3/15 TABLE 7 of the Marine Vessel Rules are to be designed, constructed and tested in accordance
with the requirements of 6-1-7/12.

Manufacturer’s tests for semiconductor converters that are used to control motor drives having a rated
power less than 100 kW (135 hp) for essential services (see definition in 4-1-1/3.5) or for services
indicated in 4-8-3/15 TABLE 7 of the Marine Vessel Rules are to include at least the tests described in
6-1-7/12.7. All other semiconductor converters used to control motor drives are to be designed, constructed
and tested in accordance with established industrial practices and manufacturer’s specifications.

The required tests may be carried out at the manufacturer facility whose certificates of tests are acceptable
and are to be submitted upon request to ABS. All semiconductor converters are subject to a satisfactory
performance test conducted to the satisfaction of the attending Surveyor after installation.

12.3 Standards of Compliance

The design of semiconductor converters for adjustable speed motor drives, unless otherwise contradicted
by ABS Rules, is to be in compliance with the requirements of IEC Publication 61800-5-1 (titled
‘Adjustable speed electrical power drive systems : Safety Requirements – Electrical, thermal and energy’)
and 60146-1-1 (titled ‘Semiconductor converters – General requirements and line commutated converters
– Specification of basic requirements). For convenience, the following requirements are listed.

12.5 Design, Construction and Assembly Requirements

12.5.1 Rating
Semiconductor converters are to be rated for continuous load conditions and if required by the
application, are to have specified overload capabilities.

The operation of the semiconductor converter equipment, including any associated transformers,
reactors, capacitors and filter circuits, is not to cause harmonic distortion and voltage and
frequency variations in excess of the values mentioned in 4-3-2/7.9 and 4-3-1/9, respectively.

The semiconductor converter circuits are to be able to withstand voltage and current transients that
the system may be subject to for certain applications.

The semiconductor converters are to be suitable for environmental conditions found in marine
installations such as those mentioned in 4-1-1/7.1 TABLE 1 and 4-1-1/7.7 TABLE 2.

12.5.2 Enclosures
Enclosures and assemblies are to be constructed of steel or other suitable incombustible, moisture-
resistant materials and reinforced as necessary to withstand the mechanical, electro-magnetic and
thermal stresses which may be encountered under both normal and fault conditions.

Enclosures are to be of the closed type. The degree of protection of the enclosure is to be in
accordance with 4-3-3/9.7.3 TABLE 1. For HV converters, the enclosure is to satisfy the
requirements in 4-3-5/7.1 TABLE 1.

All wearing parts are to be accessible for inspection and be readily replaceable.

12.5.3 Nameplate Data

A nameplate made of corrosion resistant material is to be provided on the semi-conductor
assembly and is to indicate at least the following:

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i) Manufacturer’s name and identification reference/equipment serial number

ii) Number of input and output phases
iii) Rated input voltage and current
iv) Rated output voltage and current
v) Rated input and output frequency, if any
vi) Range of output frequency
vii) Maximum permissible prospective symmetrical rms short-circuit current of the power
source
viii) Cooling methods
ix) Degree of protection
12.5.4 Warning Labels
Appropriate warning labels informing the user of the dangers with working with the different parts
of the converter assembly is to be placed at all appropriate places of the assembly.

12.5.5 Hand Rails

Insulated handrails or insulated handles are to be provided for each front panel of the assembly.
Where access to the rear is also required, insulated handrails or insulated handles are to be fitted to
the rear of the assembly as well.

12.5.6 Accessibility
All components of the semiconductor converter assembly are to be mounted in such a manner that
they can be removed from the assembly for repair or replacement without having to dismantle the
complete unit.

12.5.7 Capacitor Discharge

Capacitors within a semiconductor converter assembly is to be discharged to a voltage less than 60
V, or to a residual charge less than 50 µC, within 5 seconds after the removal of power. If this
requirement cannot be met, appropriate warning labels are to be placed on the assembly.

12.5.8 Cooling Arrangements

Design of cooling systems is to be based on an ambient air temperature of 45°C (113°F) indicated
in 4-1-1/7.7 TABLE 2.

Semiconductor converter assemblies are to be installed away from sources of radiant energy in
locations where the circulation of air is not restricted to and from the assembly and where the
temperature of the inlet air to air-cooled converters do not exceed that for which the converter has
been designed.

Where arrangements for forced cooling have been provided, the equipment is, unless otherwise
specifically required, to be designed such that power cannot be applied to, or retained on, the
semiconductor circuits, unless effective cooling is maintained. Other effective means of protection
against equipment over-temperature such as reduction in the driven load are also acceptable.

Semiconductor assemblies with forced cooling are to be provided with a means of monitoring the
temperature of the cooling medium. Over-temperature of the cooling medium is to be alarmed
locally and at a continuously manned location and the equipment shutdown when temperature
exceeds the manufacturer specified value.

Semiconductor assemblies with liquid cooling are to be provided with a means to detect leakage.
In case of leakage, an audible and visible alarm is to be initiated locally and remotely at a
continuously manned location. Means to contain any leakage are to be provided so that the liquid

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does not cause a failure of the semiconductor assembly or any other electrical equipment located
near the converter. Where the cooling liquid is required to be non-conducting, the conductivity of
the cooling liquid is to be monitored and an alarm given both locally and remotely in a
continuously manned location if the conductivity exceeds the manufacturer specified value.

In case of failure of the cooling system, an alarm is to be given both locally and remotely at a
continuously manned location and the output current is to be reduced automatically.

Cooling liquids which are in contact with live unearthed parts of the assembly are to be non-
conductive and non-flammable.

12.5.9 Emergency Stop

When required, semiconductor converter assemblies are to be provided with an emergency stop
function. The emergency stop circuit is to be hard-wired and independent of any control system
signal.

12.5.10 Electrical Protection

12.5.10(a) Overvoltage Protection.
Means are to be provided to prevent excessive overvoltage in a supply system to which
semiconductor converters are connected and to prevent the application of voltages in excess of the
rating of semiconductor devices.

12.5.10(b) Overcurrent Protection.

Arrangements are to be made so that the permissible current of semiconductor converters or
semiconductor devices associated with the semiconductor converter cannot be exceeded during
operation.

12.5.10(c) Short Circuit Protection.

Semiconductor converters and the associated semiconductor devices are to be protected against
short circuit.

12.5.10(d) Filter Circuits.

Filter circuits are to be protected against overvoltage, overcurrent and short circuit.

12.5.10(e) Alarms.
Visual and audible alarms are to be provided at the control station in the event of operation of the
protection system.

12.5.11 Clearance and Creepage Distances

Clearance and creepage distances used in standard production (COTS) semiconductor converter
assemblies are to be in accordance with IEC 61800-5-1 and suitable for overvoltage category III,
pollution degree 3 and insulating material group IIIa. The relevant values are reproduced in the
Table below for convenience.

System Voltage (V) Minimum Clearance Distance (mm)

≤ 50 0.8

100 0.8

150 1.5

300 3.0

600 5.5

1000 8.0

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System Voltage (V) Minimum Clearance Distance (mm)

3600 25

7200 60

12000 90

15000 120

Note: Interpolation is permitted.

Working Voltage (rms) (V) Minimum Creepage Distance (mm)

50 1.9

100 2.2

125 2.4

160 2.5

200 3.2

250 4.0

320 5.0

400 6.3

500 8.0

630 10.0

800 12.5

1000 16

1250 20

1600 25

2000 32

2500 40

3200 50

4000 63

5000 80

6300 100

8000 125

10000 160

Note: Interpolation is permitted.

12.5.12 Protection and Monitoring Requirements

Semiconductor assemblies, as a minimum, are to have alarm functions for the following
parameters:

i) Overcurrent
ii) Overload
iii) Overvoltage

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iv) Ground fault

v) Loss of cooling
vi) Increase in resistivity of cooling medium (for liquid cooled converters)
vii) Over-temperature
viii) Loss of communication to process control
ix) Loss of motor speed feedback

If harmonic filters are used in conjunction with semiconductor converter assemblies, refer to
4-3-2/9.19 for additional protection requirements.

For units with electric propulsion, refer to 4-9-6/23 TABLE 4A of the Marine Vessel Rules.

12.5.13 Load-Sharing
When semiconductor converters have multiple parallel/series circuits, load sharing between the
multiple circuits is to be distributed uniformly, as far as practicable.

12.5.14 EMC Emission Requirements

If requested by the customer, EM immunity and EM emissions testing of the semiconductor
assembly is to be done as an optional test in accordance with IEC 61800-3 (titled ‘Adjustable
speed electrical power drive systems – Part 3: EMC requirements and specific test methods’)

Note:

Radiated and conducted emissions/immunity does not depend on the equipment alone but also on the interaction
between the semiconductor converter assembly and the rest of the power system. There shall be communication
between the manufacturer and the customer as to what installation guidelines may need to be followed to satisfy
the different EM emission/immunity requirements, such as cable routing, types of interconnect cables used, cable
shielding, etc.

12.5.15 Harmonic Filter Requirements

If harmonic filter circuits are used in association with semiconductor converter assemblies to
reduce the harmonics and transients in the system, they are to comply with the requirements in
4-3-2/9.19.

12.5.16 Performance
The converter control system is to be able to control the motor by speed ramp, torque or power, as
per customer specification.

Upon loss of the reference signal, the converter is to either decelerate the driven motor to
minimum speed/torque/power or down to standstill as per customer specification for the required
application.

When, during normal operation, the motor is decelerated to standstill, it is to be possible to de-
energize the motor by blocking the control signals to the power semiconductors, while leaving the
converter input circuit energized.

When automatic restart is specified, the converter is to be capable of catching an already spinning
motor.

12.7 Inspection and Testing

Semiconductor assemblies for motor drives are to undergo Type tests, Routine tests and Optional tests, if
any specifically required by the Owner, at manufacturer’s production facility as per the Table below. The
Type tests, Routine tests and Optional tests are to be conducted in the presence of and witnessed by an

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ABS Surveyor. Type tests are to be carried out one prototype of a converter or the first of a batch of
identical converters. Routine tests are to be carried on each assembly. A summary of the required type tests
and routine tests are given in the Table below:

No. Tests Type Test Routine ABS Reference IEC Test Reference
(see 6-1-7/12.7) Test

1 Visual inspection X X 6-1-7/12.7.1 61800-5-1/5.2.1

2 Insulation test (AC or DC voltage test) X X 6-1-7/12.7.2 61800-5-1/5.2.3.2

3 Insulation resistance test X X 6-1-7/12.7.4 60146-1-1/7.2.3.1

4 Impulse voltage test X 6-1-7/12.7.3 61800-5-1/5.2.3.1

5 Cooling system test X X 6-1-7/12.7.5 61800-5-1/5.2.4.5

6 Breakdown of components test X 6-1-7/12.7.6 61800-5-1/5.2.3.6.4

7 Light load and functional test X X 6-1-7/12.7.7 60146-1-1/7.3.1

8 Rated current test X 6-1-7/12.7.8 60146-1-1/7.3.2

9 Temperature rise test X 6-1-7/12.7.9 61800-5-1/5.2.3.8

10 Capacitor discharge test X 6-1-7/12.7.10 61800-5-1/5.2.3.7

12.7.1 Visual Inspection

Semiconductor assemblies are subject to visual inspection for the following aspects:

i) Verify enclosure integrity, alignment of different cabinets in the assembly as per system
drawings.
ii) Verify if nameplate is present as per 6-1-7/12.5.3.
iii) Check if adequate and visible warning and safety labels are present.
iv) General hardware and electrical point-to-point wire check.
v) Verify correct routing and connections of fiber optic cables and ethernet cables.
vi) Verify correct connection of grounding wires on the assembly.
vii) Point-to-point inspection of cooling system. For drive assemblies with liquid cooling,
verification of proper installation of piping and hoses, correct orientation of flow
restrictors and related coolant liquid monitoring instrumentation.
viii) Door interlocks, if any
12.7.2 Insulation Test (AC or DC Voltage Test)
Semiconductor assemblies are subject to insulation tests to ensure adequate dielectric strength of
insulation of its components and to verify that clearance distances have not been compromised
during manufacturing operations. The insulation test is to be performed with the appropriate AC
or DC voltage (equal to the peak value of the specified AC rms voltage) mentioned in Table 21/
Table 22/Table 23 of IEC 61800-5-1. The AC test voltage is to be voltage of sinusoidal wave form
and a frequency of 50 Hz/60 Hz. The duration of the test is to be at least 5 sec for the Type Test
and 1 sec for the Routine Test. All main power, control power and logic circuits have to be subject
to the Insulation test.

12.7.3 Impulse Voltage Test

Semiconductor assemblies are subject to an Impulse voltage test to simulate the impact of impulse
transient over voltages generated in the mains supply or those caused by switching of equipment.
The impulse voltage test is to be done as per 5.2.3.1 of IEC 61800-5-1(2007). For purposes of

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selection of test voltages, the semiconductor assembly is to be treated as belonging to overvoltage

category III.

Impulse voltage tests are to be done as a routine test on assemblies that do not satisfy the clearance
and creepage distance requirements of 6-1-7/12.5.11.

12.7.4 Insulation Resistance Test

One minute after the insulation test, insulation resistance is to be measured by applying a direct
voltage of at least 500 V.

12.7.5 Cooling System Test

Semiconductor assemblies are subject to cooling system tests that test for failure of the cooling
system and the associated response of the semiconductor assembly to these cooling system
failures as per 5.2.4.5 of IEC 61800-5-1.

In addition, for liquid cooled semiconductor assemblies, the cooling piping system shall be subject
to a coolant leak pressure test. The cooling system piping is to be hydrostatically tested to 1.5
times the design pressure for a period of 30 minutes. The pressure relief mechanism is also to be
checked for proper calibration and operation. The cooling system is to be verified as having no
leakage by monitoring the pressure and by visual inspection.

The instrumentation critical to the operation of the cooling system such as valve positions,
programming of level switch sensors, flow sensors, pressure sensors, temperature sensors,
pressure relief valve operation, coolant conductivity sensor, etc., is to be checked to ensure correct
calibration and functionality.

12.7.6 Breakdown of Components Test

Components which have been identified by circuit analysis could result in a thermal or electric
shock hazard are to be subject to a breakdown test as per 5.2.3.6.4 of IEC 61800-5-1.

12.7.7 Light Load and Functional Test

Semiconductor assemblies are subject to a light load and functional test to ensure that all parts of
the electrical circuit and the cooling system work properly together and that the assembly meets
the required proof of performance as per customer requirements. The main things to be checked
include, but are not limited to:

i) Verify that the control equipment, auxiliaries, protection equipment and main circuit are
operating properly together.
ii) Check power supplies to different power and control circuits of the assembly and
associated communication control interfaces.
iii) Check pre-charge circuit settings.
iv) Verify the various software parameters.
v) Check for voltage/current sharing in the semiconductor devices used in the arms of the
converter.
vi) Testing of the converter for scenarios like, but not limited to, emergency trip of the
assembly, input fault protection, loss of cooling, local and remote control operation, etc.
vii) Testing of the converter for any specific customer defined scenario like output power
ramp-down on loss of input power, ability of the converter to catch a spinning motor after
recovering from a trip or from automatic restart, etc.

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12.7.8 Rated Current Test

The test is carried out to verify that the equipment operates satisfactorily at rated current. The DC
terminals are to be short-circuited directly or with a reactor and an alternating voltage of sufficient
value, to cause at least the rated continuous direct current to flow, is to be connected to the AC
terminals of the converter and operation of the assembly is to be checked.

12.7.9 Temperature Rise Test

The test is carried out to verify that parts and accessible surfaces of the semiconductor assembly
do not exceed temperature limits specified below and the manufacturer’s temperature limits of
safety-relevant parts. The temperature rise test is to be conducted at worst-case conditions of rated
power and rated output current.

Materials and Components Thermometer Method (°C) Resistance Method (°C)

Rubber/Thermoplastic-insulated conductors 55 –

User terminals Note 1 –

Copper bus bars and connecting straps 120 –

Winding Insulation
Class A 95 105
Class E 100 115
Class B 105 125
Class F 115 135
Class H 135 155
Class N 175 195

Phenolic composition 145 –

Bare resistor material 395 –

Capacitor Note 2 –

Power switching semiconductors Note 2 –

Printed wiring boards (PWB’s) Note 2 –

Liquid cooling medium Note 2 –

Notes:

1 Maximum terminal temperature shall not exceed 15°C more than the insulation temperature rating of the
conductor or cable specified by the manufacturer.

2 Maximum temperature shall be as specified by the manufacturer.

12.7.10 Capacitor Discharge Test

Verification of the capacitor discharge time as required in 6-1-7/12.7.7 is required to be done by a
test and/or by calculation.

12.9 Integration Requirements

12.9.1 Integration
In cases where the semiconductor converters are integrated into larger assemblies that have other
components (i.e., transformers, reactors, motors, etc.), the individual tests of the other components
are to be done in accordance with relevant portions of the ABS Rules.

Installation requirements such as earthing of equipment, selection of cable and acceptable cable
lengths, etc., should be as per manufacturer installation guidelines.

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12.9.2 Reactors and Transformers for Semiconductor Converters

12.9.2(a) Voltage Regulation.
Means to regulate transformer output voltage are to be provided to take care of increase in
converter forward resistance and, in addition, to obtain the necessary performance characteristics
of the converter unit in which the transformer is used.

12.9.2(b) High Temperature Alarm.

Interphase reactors and transformers used with the semiconductor converters for main and
auxiliary propulsion systems are to be provided with a high temperature alarm at the switchboard
or the propulsion control station. The setting value of the alarm is to be determined by their
specific insulation class and is not to exceed the temperature corresponding to the limit listed in
6-1-7/19.23 TABLE 9.

12.9.3 Critical Speeds

The semiconductor converter supplier, the driven equipment supplier and the Owner should come
to an agreement on the calculations of the resulting critical lateral speeds of the whole mechanical
string with special attention being paid to the following:

i) Take into account the influence of the stiffness of the bearing arrangement and the
foundation.
ii) Avoid any continuous running with insufficient damping close to lateral critical speeds
(±20%).

13 Other Electric and Electronics Devices

13.1 Circuit Breakers

13.1.1 General
Circuit breakers are to be constructed and tested to comply with IEC Publication 60947-2 or other
recognized standard. The tests can be carried out by the manufacturer whose certificate of tests are
acceptable and is to be submitted upon request from ABS. Circuit breakers of the thermal type are
to be calibrated for an ambient-air temperature as provided in 4-3-1/17.

Note:

Where thermal-type breakers are mounted within enclosures, it is pointed out that the temperature within the
enclosure may exceed the designated ambient-air temperature.

13.1.2 Mechanical Property

Arc-rupturing and main contacts of all open frame circuit breakers are to be self-cleaning.

13.1.3 Isolation
The electrical system is to be arranged so that portions can be isolated to remove circuit breakers
while maintaining services necessary for propulsion and safety of the unit, or circuit breakers are
to be mounted or arranged in such a manner that the breaker can be removed from the front
without disconnecting the copper or cable connections or without de-energizing the supply to the
breaker.

13.3 Fuses
Fuses are to be constructed and tested to comply with IEC Publication 60269 or other recognized standard.
The tests can be carried out by the manufacturer whose certificate of tests are acceptable and is to be
submitted upon request from ABS. All components of the fuse are to be resistant to heat, mechanical
stresses and corrosive influences which occur in normal use.

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13.5 Semiconductor Converters

13.5.1 General
The requirements in this subsection are applicable to static converters for essential and emergency
services using semiconductor rectifying elements such as diodes, reverse blocking triodes,
thyristors, etc. The tests can be carried out by the manufacturer whose certificate of tests are
acceptable and is to be submitted upon request from ABS. All semiconductor converters are
subject to a satisfactory performance test conducted after installation to the satisfaction of the
Surveyor.

13.5.2 Cooling Arrangements

Semiconductor converters are preferably to be of a dry and air cooled type. Where semiconductor
converters are of a liquid-immersed type, a liquid over-temperature alarm and gas overpressure
protection devices are to be provided. If provision is made for breathing, a dehydrator is to be
provided. Where arrangement for the forced cooling is provided, the circuit is to be designed that
power cannot be applied to, or retained, on converter stacks unless effective cooling is maintained.

13.5.3 Accessibility
Semiconductor converter stacks or semiconductor components are to be mounted in such a
manner that they can be removed from equipment without dismantling the complete unit.

13.5.4 Nameplate
A nameplate or identification is to be provided on the semiconductor converter and is to indicate
at least the information as listed in 6-1-7/19.23 TABLE 5.

13.7 Cable Junction Boxes

13.7.1 General
The design and construction of the junction boxes are to be in compliance with 6-1-7/13.7.2 or
other recognized standard. The tests can be carried out by the manufacturer whose certificate of
tests are acceptable and is to be submitted upon request from ABS.

13.7.2 Design and Construction

Live parts are to be mounted on durable flame-retardant, moisture-resistant material of
permanently high dielectric strength and high resistance. The live parts are to be so arranged by
suitable spacing or shielding with flame-retardant insulating material that short-circuit cannot
readily occur between conductors of different polarity or between conductors and earthed metal.
Junction boxes are to be made of flame-retardant material and are to be clearly identified, defining
their function and voltage.

15 High Voltage Systems

15.1 General
15.1.1 Application
The following requirements in this Subsection are applicable to AC systems with nominal voltage
(phase to phase) exceeding 1 kV. Unless stated otherwise, high voltage equipment and systems are
to comply with the other parts in Section 6-1-7 for low voltage equipment and systems, as well.

15.3 Machinery and Equipment

15.3.1 Rotating Machines
15.3.1(a) Protection.
Refer to 4-3-5/7.1 TABLE 1 for ingress protection (IP) requirements.

15.3.1(b) Windings.

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Generator stator windings are to have all phase ends brought out for the installation of the
differential protection.

15.3.1(c) Temperature Detectors.

Rotating machines are to be provided with temperature detectors in their stator windings to actuate
a visual and audible alarm in a normally attended position whenever the temperature exceeds the
permissible limit. If embedded temperature detectors are used, means are to be provided to protect
the circuit against over-voltage.

15.3.1(d) Space Heater.

Effective means are to be provided to prevent the accumulation of moisture and condensation
within the machines when they are idle.

15.3.2 Switchgear and Control-gear Assemblies

Switchgear and control gear assemblies are to be constructed according to the IEC Publication
62271-200 and the following additional requirements:

15.3.2(a) Mechanical Construction and Configuration.

Switchgear is to be of metal-enclosed type in accordance with IEC Publication 62271-200 or of
the insulation-enclosed type in accordance with IEC Publication 62271-201.

15.3.2(b) Clearance and Creepage Distances.

For clearance and creepage distances, see 4-3-5/1.1.3.

15.3.2(c) Locking Facilities.

Withdrawable circuit breakers and switches are to be provided with mechanical locking facilities
in both service and disconnected positions. For maintenance purposes, key locking of
withdrawable circuit breakers, switches and fixed disconnectors is to be possible. Withdrawable
circuit breakers, when in the service position, are to have no relative motion between fixed and
moving parts.

15.3.2(d) Shutters.
The fixed contacts of withdrawable circuit breakers and switches are to be so arranged that in the
withdrawn position, the live contacts of the bus bars are automatically covered. Shutters are to be
clearly marked for incoming and outgoing circuits. This may be achieved with the use of colors or
labels.

15.3.2(e) Earthing and Short-circuiting Facilities.

For maintenance purposes, earthing and short circuiting facilities are to be provided to enable
equipment and cables to be earthed or short-circuited to earth before being worked upon.

15.3.2(f) Arc Flash and Associated Installation Requirements

i) Internal Arc Classification (IAC). Switchgear and control gear assemblies are to be
Internal Arc Classified (IAC). Where switchgear and control gear are accessible by
authorized personnel only accessibility Type A is sufficient (IEC 62271-200; Annex AA;
AA 2.2). Accessibility Type B is required if accessible by non-authorized personnel.
Installation and location of the switchgear and control gear is to correspond with its
internal arc classification and classified sides (F, L and R).
ii) Calculations, in accordance with the applicable parts of Standard IEEE 1584 or other
recognized standard, are to be made to establish:

● The maximum current that can flow in the case of an arc fault
● The maximum time and current that can flow if arc protection techniques are adopted

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● The distance, from the location of the arc flash, at which the arc flash energy is 1.2
calories per cm2 if the enclosure is open
iii) In addition to the marking required by the equipment design standard, arc flash data
consistent with the Design Operating Philosophy and the required PPE is also to be
indicated at each location where work on the HV equipment could be conducted.
15.3.3 Transformers
15.3.3(a) Application.
Provisions of 6-1-7/15.3.3 are applicable to power transformers for essential services. See also
6-1-7/11. Items 6-1-7/15.3.3(c) and 6-1-7/15.3.3(d) are applicable to transformers of the dry type
only. These requirements are not applicable to transformers intended for the following services:

● Instrument transformers.
● Transformers for static converters.
● Starting transformers.

Dry type transformers are to comply with the applicable Parts of the IEC Publication 60076-11.
Liquid filled transformers are to comply with the applicable Parts of the IEC 60076 Series. Oil
immersed transformers are to be provided with the following alarms and protections:

● Liquid level (Low) - alarm

● Liquid temperature (High) - alarm
● Liquid level (Low) - trip or load reduction
● Liquid temperature (High) - trip or load reduction
● Gas pressure relay (High) - trip
15.3.3(b) Plans.
In addition to the details required in 6-1-7/11, the applicable standard of construction and the rated
withstanding voltage of the insulation are also to be submitted for review.

15.3.3(c) Enclosure.
Transformers are to have a degree of protection of at least IP23. However, when installed in
spaces accessible to unqualified personnel, the degree of protection is to be increased to IP4X,
where "X" is dependent on the liquid condition in the location in which the equipment is to be
installed (see 4-3-1/19 TABLE 3). For transformers not contained in enclosures, the degree of
protection is to be in accordance with 4-3-3/9.7.3 TABLE 1.

15.3.3(d) Space Heater.

Effective means to prevent accumulation of moisture and condensation within the transformers
(when de-energized) is to be provided.

17 Electric Propulsion System

17.1 General
17.1.1 Temperature Rating
When generators, motors or slip-couplings for electric propulsion are fitted with an integral fan
and are operated at speeds below the rated speed with full-load torque, full-load current, or full-
load excitation, temperature rise limits according to 6-1-7/19.23 TABLE 4 are not to be exceeded.

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17.1.2 Protection Against Moisture Condensation

6-1-7/5.11.7 is applicable for rotating machines and converters, regardless of the weight of the
machines.

17.1.3 Accessibility
For purposes of inspection and repair, provision is to be made for access to the stator and rotor
coils, and for the withdrawal and replacement of field coils. Adequate access is to be provided to
permit resurfacing of commutators and slip-rings, as well as the renewal and bedding of brushes.

17.3 Machinery and Equipment

17.3.1 Rotating Machines for Propulsion
The following requirements are applicable to propulsion generators and propulsion motors.

17.3.1(a) Ventilation and Protection.

Electric rotating machines for propulsion are to be enclosed ventilated or be provided with
substantial wire or mesh screen to prevent personnel injury or entrance of foreign matter. Dampers
are to be provided in ventilating air ducts, except when recirculating systems are used.

17.3.1(b) Fire-extinguishing Systems.

Electric rotating machines for propulsion which are enclosed or in which the air gap is not directly
exposed are to be fitted with fire-extinguishing systems suitable for fires in electrical equipment.
This is not required where it can be established that the machinery insulation is self-extinguishing.

17.3.1(c) Air Coolers.

Air cooling systems for propulsion generators are to be in accordance with 4-6-5/7.7.1 and
4-6-5/7.5 of the Marine Vessel Rules. Water-air heat exchangers of rotating propulsion machines
for single systems (single generator and single motor), as specified in 4-3-5/3.5.1(b), are to have
double wall tubes and be fitted with a leak detector feature to monitor for any water leakage. A
visual and audible alarm is to be provided at a normally manned location to indicate such water
leakage.

17.3.1(d) Temperature Sensors.

Stator windings of AC machines and interpole windings of DC machines, rated above 500 kW, are
to be provided with temperature sensors.

17.3.1(e) Generator Excitation.

Excitation current for propulsion generators may be derived from attached rotating exciters, static
exciters, excitation motor-generator sets or special purpose generating units. Power for these
exciters may be derived from the machine being excited or from any unit main service, emergency
or special purpose generating units.

17.3.1(f) Propulsion Motors.

Propulsion motors are to be designed to be capable of withstanding the mechanical and thermal
effects of a short-circuit at its terminals.

17.3.2 Direct-current (DC) Propulsion Motors

17.3.2(a) Rotors.
The rotors of DC propulsion motors are to be capable of withstanding overspeeding up to the limit
reached in accordance with the characteristics of the overspeed protection device at its normal
operational setting.

17.3.2(b) Overspeed Protection.

An overspeed protection device is to be provided to prevent excessive overspeeding of the
propulsion motors due to light loads, loss of propeller, etc.

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17.3.3 Electric Couplings

17.3.3(a) General.
Couplings are to be enclosed ventilated or be provided with wire or mesh screen to prevent
personnel injury or the entrance of foreign material. All windings are to be specially treated to
resist moisture, oil and salt air.

17.3.3(b) Accessibility for Repairs.

The coupling is to be designed to permit removal as a unit without moving the engine. See also
6-1-7/17.1.3.

17.3.3(c) Temperature Rating.

The limits of temperature rise are to be the same as for alternating-current generators given in
6-1-7/19.23 TABLE 4, except that when a squirrel-cage element is used, the temperature of this
element may reach such values as are not injurious. Depending upon the cooling arrangements, the
maximum temperature rise may occur at other than full-load rating so that heat runs will require
special consideration. For this purpose, when an integral fan is fitted, the coupling temperatures
are not to exceed the limits in 6-1-7/19.23 TABLE 4 when operated continuously at 70% of full-
load rpm, full excitation and rated torque. Temperature rises for insulation materials above 180°C
(356°F) are subject to ABS technical assessment and approval in accordance with 6-1-7/1.3.6.

17.3.3(d) Excitation.
Excitation is to be provided as required for propulsion generators. See 6-1-7/5.17.1,
6-1-7/5.19.1,6-1-7/17.3.1(e) .

17.3.3(e) Control Equipment.

Electric-coupling control equipment is to be combined with the prime mover speed and reversing
control and is to include a two-pole disconnect switch, short-circuit protection only, ammeter for
reading coupling current, discharge resistor and interlocking to prevent energizing the coupling
when the prime mover control levers are in an inappropriate position.

17.3.3(f) Nameplates.
Nameplates of corrosion-resistant material are to be provided in an accessible position of the
electric coupling and are to contain the following typical details:

● Manufacturer’s name, serial number and frame designation

● Rated output and type of rating
● Ambient temperature range
● Rated voltage, speed and temperature rise
● Rated exciter voltage and current
17.3.4 Semiconductor Converters for Propulsion
Semiconductor converters are to comply with the requirements in 6-1-7/12.

17.3.5 Reactors and Transformers for Semiconductor Converters

17.3.5(a) General.
Interphase reactors and transformers used with semiconductor converters are to conform with the
requirements of 6-1-7/11.1.1, 6-1-7/11.1.2(c), 6-1-7/11.3, 6-1-7/11.5.1 and 6-1-7/11.5.2 and the
following.

17.3.5(b) Voltage Regulation.

Means to regulate transformer output voltage are to be provided to take care of the increase in
converter forward resistance and, in addition, to obtain the necessary performance characteristics
of the converter unit in which the transformer is used.

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17.3.5(c) High Temperature Alarm.

See 6-1-7/12.9.2(b).

17.3.6 Propulsion Cables

17.3.6(a) Conductors.
The conductors of cables external to the components of the propulsion plant, other than cables and
interconnecting wiring for computers, data loggers or other automation equipment requiring
currents of very small value, are to consist of not less than seven strands and have a cross-
sectional area of not less than 1.5 mm2 (2,960 circ. mils).

17.3.6(b) Insulation Materials

Ethylene-propylene rubber,

cross-linked polyethylene, or silicone rubber insulated cables are to be used for propulsion power
cables. PVC insulated cables are not acceptable as per IEC 60092-360.

17.3.6(c) Braided Metallic Armor and Impervious Metallic Sheaths.

Propulsion cables need not have braided metallic armor nor impervious metallic sheaths. Where
metallic sheaths are provided, they are not to be used with single alternating current cables.

17.3.6(d) Inner Wiring.

The insulation of internal wiring in main control gear, including switchboard wiring, is to be of
flame-retardant quality.

19 Survey and Certification

Where required, type-testing and unit certification is to be carried out, in presence of and to the satisfaction
of the Surveyor, at manufacturer's plant and reported upon before installation onboard. The extent of
services required for each electrical cable, equipment, and machinery are indicated in 6-1-7/19.23 TABLE
1. Where a product does not require unit certification, Surveyor attendance is optional, and the product is
to be designed and fabricated to satisfy a recognized industrial standard and the manufacturer's
specification.

For the purpose of this subsection, the reference to essential services means essential services as defined in
4-1-1/3.5 and services related to additional optional notations requested for the unit.

Following paragraphs define the requirements for survey and certification of products manufactured in
presence of a Surveyor.

19.1 Generators and Motors ≥ 100 kW (135 hp) intended for Essential Services
Factory testing schedule required for generators and motors of 100 kW (135 hp) and over intended for
essential services are indicated with an "X" mark in 6-1-7/19.23 TABLE 2. Requirements for compliance
are further referenced in 6-1-7/5.1 through 6-1-7/5.19, 6-1-7/19.23 TABLE 3 and 6-1-7/19.23 TABLE 4.

Construction and assembly of rotating machines are to be verified in compliance with 6-1-7/5.11 and their
nameplates are to indicate at least the information as listed in 6-1-7/19.23 TABLE 5.

All generators and motors ≥ 100 kW (135 hp) intended for essential services are to be examined and tested
in presence of and to the satisfaction of the Surveyor. Examination and testing of other generators and
motors may be carried out without a Surveyor’s presence, but the manufacturer’s test certificate is to be
available to the Surveyor attending construction of the unit at shipyard.

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19.3 Propulsion Generators and Motors

Requirements for survey and certification of propulsion generators and motors, regardless of their power,
are same as generators and motors ≥ 100 kW (135 hp) intended for essential services, as indicated in
6-1-7/19.1.

19.5 Switchboards
Factory testing schedule required for switchboards intended for main power, emergency power and
propulsion system are indicated with an "X" mark in 6-1-7/19.23 TABLE 6. Requirements for compliance
are further referenced in 6-1-7/9.1 through 6-1-7/9.13, 6-1-7/19.23 TABLE 7, and 6-1-7/19.23 TABLE 8.

Construction and assembly of switchboards are to be verified in compliance with 6-1-7/9.7.

All switchboards intended for main power, emergency power and propulsion system are to be examined
and tested in presence of and to the satisfaction of the Surveyor. Examination and testing of other boards
may be carried out without a Surveyor’s presence but the manufacturer’s test certificate is to be available
to the Surveyor attending construction of the drilling unit at shipyard.

19.7 Motor Controllers and Control Centers intended for Essential Services ≥ 100 kW (135
hp)
Factory testing schedule required for motor controllers and control centers intended for essential services ≥
100 kW (135 hp) are indicated with an "X" mark in 6-1-7/19.23 TABLE 6. Requirements for compliance
are further referenced in 6-1-7/9.1 through 6-1-7/9.11, 6-1-7/19.15, 6-1-7/19.23 TABLE 7.

Construction, enclosures and assembly of motor controllers and control centers are to be verified in
compliance with 6-1-7/9.15.

All motor control centers with aggregate loads ≥ 100 kW intended for essential services are to be examined
and tested in the presence of and to the satisfaction of the Surveyor. Examination and testing of other
motor control centers may be carried out without a Surveyor’s presence but the manufacturer's test
certificate is to be available to the Surveyor attending construction of the unit at shipyard.

19.9 Battery Charging Units ≥ 25 kW, UPS units ≥ 50 kVA, and Associated Distribution
Boards, for Essential, Emergency or Transitional Source of Power
Factory testing schedule required for battery charging units ≥ 25 kW, UPS units ≥ 50 kVA, and associated
distribution boards, for essential, emergency or transitional source of power are indicated with an "X"
mark in 6-1-7/19.23 TABLE 6. Requirements for compliance are further referenced in 6-1-7/9.1 through
6-1-7/9.11, 6-1-7/9.17.

Construction, enclosures and assembly of motor controllers and control centers are to be verified in
compliance with 6-1-7/9.15 and their nameplates are to indicate at least the information as listed in
6-1-7/19.23 TABLE 5.

Appropriate testing is to be carried out to demonstrate that the battery charger units and uninterruptible
power system (UPS) units are suitable for the intended environment. This is expected to include as a
minimum the following tests:

i) Functionality, including operation of alarms;

ii) Temperature rise;
iii) Ventilation rate; and
iv) Battery capacity.

Where the supply is to be maintained without a break following a power input failure, this is to be verified
after installation by practical test.

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All battery charging units ≥ 25 kW, UPS units ≥ 50 kVA, and associated distribution boards, for essential,
emergency or transitional source of power are to be tested in presence of and to the satisfaction of the
Surveyor. Testing of all other battery charging units, UPS units, and associated distribution boards may be
carried out without a Surveyor’s presence but the manufacturer’s test certificate is to be available to the
Surveyor attending construction of the unit at shipyard.

19.11 Power Transformers ≥ 100 kVA and Converters for High Voltage Systems over 1 kV,
for Essential or Emergency Source of Power
Factory testing schedule required for power transformers ≥ 100 kVA and converters for high voltage
systems over 1 kV, for essential or emergency source of power are indicated with an "X" mark in
6-1-7/19.23 TABLE 6. Requirements for compliance are further referenced in 6-1-7/9.3 through
6-1-7/9.11, 6-1-7/11.

Construction and assembly of power transformers ≥ 100 kVA and converters for high voltage systems over
1 kV are to be verified in compliance with 6-1-7/11.5 and their nameplates are to indicate at least the
information as listed in 6-1-7/19.23 TABLE 5.

All power transformers ≥ 100 kVA and converters for high voltage systems over 1 kV, for essential or
emergency source of power are to be tested in presence of and to the satisfaction of the Surveyor. Testing
of all other transformers and converters may be carried out without a Surveyor’s presence but the
manufacturer’s test certificate is to be available to the Surveyor attending construction of the unit at
shipyard.

For single-phase transformers rated 1 kVA and above or three-phase transformers rated 5 kVA and above
intended for essential or emergency services, the following tests are to be carried out by the transformer’s
manufacturer in accordance with a recognized standard:

i) Measurement of winding resistance, voltage ratio, impedance voltage, short circuit impedance,
insulation resistance, load loss, no load loss and excitation current, phase relation and polarity;
ii) Dielectric strength; and
iii) Temperature rise (required for one transformer of each size and type). See 6-1-7/11.3.

19.13 Semiconductor Converters for Propulsion (only for Self-Propelled Units)

Semiconductor converters for propulsion systems are to be tested to the type test requirements of the
relevant standard.

If the standard is the IEC 60146 Series, then type tests are to include the following:

i) Insulation test;
ii) Light load and function test;
iii) Rated current test;
iv) Power loss;
v) Temperature rise test; and
vi) Checking the auxiliary devices, properties of the control equipment and protective devices.

Duplicate units of previously tested semiconductor converters are to be tested to the routine test
requirements of the relevant standard.

If the standard is the IEC 60146 Series, then the routine tests are to include the following:

i) Insulation test;
ii) Light load and function test; and

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iii) Checking the auxiliary devices, properties of the control equipment and protective devices.

19.15 Propulsion Cables other than Internal Wiring in Control Gears and Switchboards (only
for Self-Propelled Units)
All propulsion cables other than internal wiring in control gears and switchboards are to be subjected to
dielectric and insulation tests.

19.17 Controls for Electric Propulsion Equipment (only for Self-Propelled Units)
Controls for electric propulsion equipment are to be inspected when finished and dielectric strength tests
and insulation resistance measurements made on the various circuits in the presence of the Surveyor,
preferably at the plant of manufacture. The satisfactory tripping and operation of all relays, contactors and
the various safety devices are also to be demonstrated.

19.19 High Voltage (HV) Systems - Rotating Machinery

Each design of HV generator and motor is to be assessed by testing in accordance with the “type tests”
schedule indicated in 6-1-7/19.23 TABLE 2. Each subsequent production unit of and accepted design is to
be tested in accordance with the “routine tests” schedule also indicated in 6-1-7/19.23 TABLE 2.

19.19.1 Inter-turn Insulation Test

In addition to the tests normally required for rotating machinery, a high frequency, high voltage
test, in accordance with IEC Publication 60034-15, is to be carried out on the individual coils in
order to demonstrate a satisfactory withstand level of the inter-turn insulation to steep fronted
switching surges.

19.19.2 Insulation Resistance

Immediately after the high voltage test the insulation resistance is to be measured using a direct
current insulation test meter between:

i) All current carrying parts connected together and earth

ii) All current carrying parts of different polarity or phase where both the ends of each
polarity or phase are individually accessible.

The minimum values of test voltage and corresponding insulation resistance are given in the table
below. The insulation resistance is to be measured close to the operating temperature. If this is not
possible then an approved method of calculation is to be used.

Rated Voltage, Un Minimum Test Voltage Minimum Insulation Resistance

(V) (V) (MΩ)

1000 < Un ≤ 7200 1000 Un/1000 + 1

7200 < Un ≤15000 5000 Un/1000 + 1

19.21 High Voltage (HV) Systems - Switchgear and Control-Gear Assemblies

A power frequency voltage test is to be carried out on high voltage switchgear and control-gear assemblies
with test voltages shown in Table below. The test procedure is to be in accordance with IEC Publication
62271-200.

Rated Voltage Rated Power Frequency Withstand Voltage

(kV) (kV)

3.6 10

7.2 20

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Rated Voltage Rated Power Frequency Withstand Voltage

(kV) (kV)

12 28

15 38

Where intermediate values of switchgear rated voltages are used, the next higher power frequency
withstand test voltage is to be used.

19.23 High Voltage (HV) Systems -Transformers

Three-phase transformers or three-phase bank transformers of 100 kVA and above are to be tested in
accordance with the standard applicable to the transformer. Specific requirements are applicable for the
following tests:

i) In the dielectric strength test, the short duration power frequency withstand voltage to be applied
is to follow the standard applicable to the transformer but not less than the estimated voltage
transient generated within the system. If the short duration power frequency withstand voltage is
not specified in the applicable standard, IEC 60076-3 is to be referred to. For the voltage transient,
see 4-3-5/1.7.2(c).
ii) The induced over-voltage withstand test (layer test) is also to be carried out in accordance with the
standard applicable to the transformers in the presence of the Surveyor. This test is intended to
verify the power-frequency withstand strength along the winding under test and between its phase
(strength between turns and between layers in the windings). If the induced over-voltage withstand
test is not specified in the applicable standard, IEC 60076-3 is to be referred to.

In addition to the requirements in 6-1-7/19.23 TABLE 5, the following information is also to be indicated
on the nameplate:

● Applicable standard; and

● Short duration power frequency withstand voltage for verification of insulation level of each winding.

Testing of all other transformers may be carried out without a Surveyor’s presence but the manufacturer’s
test certificate is to be available to the Surveyor attending construction of the unit at shipyard.

TABLE 1
Certification Details – Electrical Systems and Control Equipment

Electrical Systems and Control Equipment ABS Rule Reference

Approval Tier

Generators and motors ≥ 100 kW (135 hp) intended for essential services 4/5 6-1-7/5,6-1-7/19.1 (See Note
1)

Generators and motors < 100 kW (135 hp) intended for essential services 1 6-1-7/5.1.1 (See Note 1)

Other Generators and motors intended for non-essential services 1 6-1-7/19, 6-1-7/19.1

Propulsion generators and motors 5 6-1-7/17, 6-1-7/19.3

Switchboards (propulsion, main and emergency) 4/5 6-1-7/19.5

Other Electrical Boards 2 6-1-7/19.5

Motor controllers ≥ 100 kW (135 hp) intended for essential services 4/5 6-1-7/19.7

Motor control centers with aggregate load ≥ 100 kW (135 hp) intended 5 6-1-7/9.15
for essential services

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Electrical Systems and Control Equipment ABS Rule Reference

Approval Tier

Battery charging units ≥ 25 kW, UPS units ≥ 50 kVA and associated 4/5 6-1-7/19.9
distribution boards, for essential, emergency or transitional source of
power

Other battery charging units, UPS units, and associated distribution 1 6-1-7/19.19
boards

Power transformers ≥ 100 kVA and converters for high voltage systems 4/5 6-1-7/19.11
exceeding 1 kV, for essential or emergency source of power

Power transformers < 100 kVA and converters for low voltage systems 2 6-1-7/19.11
of 1 kV and below, for essential or emergency source of power

Semiconductor converters that are used to control motor drives having a 4/5 6-1-7/12.7
rated power of 100 kW (135 hp) and over intended for essential services

Semiconductor converters for propulsion (only for self-propelled units) 4/5 6-1-7/19.13

Cables 2 6-1-7/19.15

Propulsion cables other than internal wiring in control gears and 4/5 6-1-7/19.17
switchboards (only for self-propelled units)

Circuit breakers and fuses 1 6-1-7/13.1, 6-1-7/13.3

Certified equipment (for installation in hazardous areas) 2 4-3-3/9

Controls, monitoring and safety system devices, including computers, 4/5 4-3-4/5
programmable logic controllers, etc., intended for automation systems

Complete assembly or subassembly units intended for automation 4/5 4-3-4/5

systems

Controls for electric propulsion equipment 5 6-1-7/19.17

HV rotating machinery 4/5 6-1-7/19.19

HV switchgear and control-gear assemblies 4/5 6-1-7/19.21

HV three-phase transformers or three-phase bank transformers ≥ 100 5 6-1-7/19.23.ii

kVA

All Non-Essential Services HV transformers 1 6-1-7/19.23

Boiler Control system 5 6-1-5/1, MVR 4-4-1/11.5,

4-9-3/9.3.4, 4-9-3/11.9

Governors for prime movers ≥ 100 kW (135 hp), intended for essential 2 6-1-3/3.3-3.5
services

CPP control system (only for self-propelled units) 5 6-1-4/1, 4-3-4/5

Steering control system and computer based steering system (only for 5 6-1-4/1, MVR 4-3-4/13.9,
self-propelled units) 4-9-3/9.3.4, 4-9-3/11.9

Control, Safety and Automatic Shutdown systems for generators driven 4/5 6-1-3/1, MVR 5C-8-A8/15.1,
by gas turbines using gas as fuel 5C-13-10/A1-15.1

Control, Safety and Automatic Shutdown systems for generators driven 4/5 6-1-3/1, MVR 4-2-1/13.7.4,
by engines using gas as fuel 4-9-9, 5C-8-16/7.3, 5C-8-
A7/5, 5C-8-A7/7.3.2, 5C-8-
A7/3.7, 5C-13-15/7,
5C-13-15/11.5

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Notes:
1 For jacking gear motors, refer to 6-1-9/25.5.5 TABLE 2, “Certification Details – Jacking and
Associated Systems”.

TABLE 2
Factory Testing Schedule for Generators and
Motors ≥ 100 kW (135 hp) (8, 9) [See 6-1-7/19.1 and 6-1-7/19.3]

Tests AC Generators AC Motors DC Machines

Type Routine Type Routine Type Routine

Test (1) Test (2) Test (1) Test (2) Test (1) Test (2)

1. Visual inspection X X X X X X

2. Insulation resistance measurement X X X X X X

3. Winding resistance measurement. X X X X X X

4. Verification of voltage regulation system. X X (3) – – – –

5. Rated load test and temperature rise measurement. X – X – X –

6. Overload/over-current test. X X (4) X X (4) X X (4)

7. Verification of steady short circuit condition. (5) X – – – – –

(6) (6) (6)
8. Over-speed test. X X X X X X (6)

9. Dielectric strength test. X X X X X X

(7)
10. Running balance test. X X X X X X

11. Verification of degree of protection. X – X – X –

12. Bearing check after test. X X X X X X

13. Air gap measurement. X X – – X X

14. Commutation check. – – – – X –

Notes:

1 Type tests apply to prototype machines or to at least the first of a batch of machines. After type test, generator
components, randomly selected at the discretion of the Surveyor, are to be presented for inspection.

2 Machines to be routine tested are to have reference to the machine of the same type that has passed a type test.
Reports of routine tested machines are to contain manufacturers’ serial numbers of the type tested machines
and the test results.

3 Only functional test of voltage regulator system.

4 Applicable only to generators and motors ≥ 100 kW (135 hp) for essential services.

5 Verification at steady short circuit condition applies to synchronous generators only.

6 Where so specified and agreed upon between purchaser and manufacturer. Not required for squirrel cage
motors.

7 Static balance (machine rated 500 rpm or less) or dynamic balance (over 500 rpm) will be accepted in lieu of
the specified test on machines to be close-coupled to engines and supplied without shaft and/or bearings, or
with incomplete set of bearings.

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8 The tests in 6-1-7/Table 2 are to be documented. The documentation is to include information on make, type,
serial number, insulation class, all technical data necessary for the application of the machine, as well as the
results of the required tests.

9 The result of type tests, and the serial number of the type tested machine, are to be specified in the
documentation of test results for routine tests.

TABLE 3
Dielectric Strength Test for Rotating Machines [See 6-1-7/5.7]

Item Machine or Part Test Voltage (AC rms)

1 Insulated windings of rotated machines having rated 500 V + twice the rated voltage.
output less than 1 kVA, and of rated voltage less than
100 V with the exception of those in items 4 to 8.

2 Insulated windings of rotating machines having rated 1,000 V + twice the rated voltage with minimum of
output less than 10,000 kVA with the exception of 1,500 V (See Note 1).
those in items 1 and 4 to 8 (See Note 2).

3 Insulated windings of rotating machines having rated 1,000 V + twice the rated voltage.
output 10,000 kVA or more, and of rated voltage (see
Note 1) up to 24,000 V with the exception of those in
items 4 to 8 (see Note 2).

4 Separately-excited field windings of DC machines. 1,000 V + twice the maximum rated circuit voltage
with minimum of 1,500 V (See Note 1).

5 Field windings of synchronous generators and

synchronous motors.

a) Field windings of synchronous generators Ten times the rated excitation voltage with a
minimum of 1,500 V and a maximum of 3,500 V.

b) When the machine is intended to be started with the Ten times the rated excitation voltage with a
field winding short-circuited or connected across a minimum of 1,500 V and a maximum of 3,500 V.
resistance of value less than ten times the resistance of
winding.

c) When the machine will be started either with: 1,000 V + twice the maximum value of the voltage
with a minimum of 1,500 V
-the field winding connected across resistance or
more than ten times the field winding resistance, or -between the terminals of the field winding,

-the field windings on open circuit or without a field or

dividing switch.
-between the terminals of any section for a
sectionalized field winding,

which will be occurred under the specified starting

conditions (see Note 3).

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Section 7 Electrical Systems and Control Equipment 6-1-7

Item Machine or Part Test Voltage (AC rms)

6 Secondary (usually rotor) windings of induction

motors or synchronous induction motors if not
permanently short-circuited (e.g., if intended for
rheostatic starting)

a) For non-reversing motors or motors reversible from 1,000 V + twice the open-circuit standstill voltage as
standstill only. measured between slip-rings or secondary terminals
with rated voltage applied to the primary windings.

b) For motors to be reversed or braked by reversing the 1,000 V + four times the open-circuit standstill
primary supply while the motor is running. secondary voltage as defined in item 6.a. above.

7 Exciters (except as listed below) As for windings to which they are connected. 1,000 V
Exception 1—Exciters of synchronous motors + twice the rated exciter voltage with a minimum of
(including synchronous induction motors) if 1,500 V.
connected to earth or disconnected from the field
winding during starting
Exception 2—Separately excited field windings of
exciters (see Item 4 above).

8 Assembled group of machines and apparatus. A repetition of the tests in items 1 to 7 above is to be
avoided if possible. But, if a test on an assembled
group of several pieces of new apparatus, each one is
made, the test voltage to be applied to such assembled
group is to be 80% of the lowest test voltage
appropriate for any part of the group (see Note 4).

Notes:

1 For two-phase windings having one terminal in common, the rated voltage for the purpose of calculating the
test voltage is to be taken as 1.4 times the voltage of each separate phase.

2 High-voltage tests on machines having graded insulation is to be subject to special consideration.

3 The voltage, which is occurred between the terminals of field windings or sections thereof under the specified
starting conditions, may be measured at any convenient reduced supply voltage. The voltage so measured is to
be increased in the ratio of the specified starting supply voltage to the test supply voltage.

4 For windings of one or more machines connected together electrically, the voltage to be considered is the
maximum voltage that occurs in relation to earth.

TABLE 4
Limits of Temperature Rise for Air-Cooled Rotating Machines
[See 6-1-7/5.9.1]

Ambient Temperature = 45°C

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Temperature Limit of Temperature Rise, °C

Item No. Part of Machine Measuring for Class of Insulation
Method A E B F H

a) AC windings of machines having rated output of 5,000 Resistance 55 — 75 95 120

kW (or kVA) or more
Embedded temp. 60 — 80 100 125
detector

b) AC windings of machines having rated output above 200 Resistance 55 70 75 100 120
1
kW (or kVA) but less than 5,000 kW (or kVA)
Embedded temp. 60 — 85 105 125
detector.

c) AC windings of machines having rated outputs of 200 Resistance 55 70 75 100 120

kW (or kVA) or less (1)

Thermometer 45 60 65 80 100
2 Windings of armatures having commutators
Resistance 55 70 75 100 120

Field windings of AC and DC machines having DC Thermometer 45 60 65 80 100

3
excitation, other than those in item 4 Resistance 55 70 75 100 120

a) Field winding of synchronous machines with cylindrical Resistance — — 85 105 130

rotors having DC excitation winding embedded in slots,
except synchronous induction motors

b) Stationary field windings of AC machines having more Thermometer 45 60 65 80 100

than one layer
Resistance 55 70 75 100 120

Embedded temp. — — 85 105 130

4 detector.

c) Low resistance field winding of AC and DC machines Thermometer 55 70 75 95 120

and compensating windings of DC machines having
Resistance 55 70 75 95 120
more than one layer

d) Single-layer windings of AC and DC machines with Thermometer 60 75 85 105 130

exposed bare or varnished metal surfaces and single
Resistance 60 75 85 105 130
layer compensating windings of DC machines (2)

5 Permanently short-circuited windings The temperature rise of any parts is not to be

detrimental to the insulating of that part or to any
6 Magnetic cores and all structural components, whether or
other part adjacent to it.
not in direct contact with insulation (excluding bearings)

7 Commutators, slip-rings and their brushes and brushing The temperature rise of any parts is not to be
detrimental to the insulating of that part or to any
other part adjacent to it.
Additionally, the temperature is not to exceed that
at which the combination of brush grade and
commutator/slip-ring materials can handle the
current over the entire operating range.

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Notes:

1 With application of the superposition test method to windings of machines rated 200 kW (or kVA) or less with
insulation classes A, E, B or F, the limits of temperature rise given for the resistance method may be increased
by 5°C.

2 Also includes multiple layer windings provided that the under layers are each in contact with the circulating
coolant.

TABLE 5
Nameplates

a. Rotating Machines [See 6-1-7/5.11.9] b. Accumulator Battery [See 6-1-7/7.3.3]

The manufacturer’s name The manufacturer’s name
The manufacturer’s serial number (or identification The type designation
mark) The rated voltage
The year of manufacture The ampere-hour rating at a specific rate of
Type of Machine (Generator or motor, etc.) discharge
Degree of protection enclosures (by IP code) The specific gravity of the electrolyte
Class of rating or duty type (in the case of a lead-acid battery, the specific
The rated output gravity when the battery is fully charged).
The rated voltage c. Transformer [See 6-1-7/11.5.3]
The rated current and type of current (AC or DC) The manufacturer’s name
The rated speed (r.p.m.) or speed range The manufacturer’s serial number (or identification
The class of insulation or permissible temperature mark)
rise The year of manufacture
The ambient temperature The number of phases
Number of phase (for AC machines) The rated power
The rated frequency (for AC machines) The rated frequency
Power factor (for AC machines) The rated voltage in primary and secondary sides
Type of winding (for DC machines) The rated current in primary and secondary sides
Exciter voltage (for synchronous machines or DC The class of insulation or permissible temperature
machines with separate excitation) rise
Exciter current at rating (for synchronous machines The ambient temperature
or DC machines with separate excitation) d. Semiconductor Converter [See 6-1-7/13.5.4]
Open-circuit voltage between slip-rings and the The manufacturer’s name
slip-ring current for rated conditions (for wounded- The identification number of the equipment
rotor induction machines)

TABLE 6
Factory Testing Schedule for Switchboards, Chargers, Motor Control Centers,
and
Controllers [See 6-1-7/19.5, 6-1-7/19.7 and 6-1-7/19.9]

1 Insulation resistance measurements in accordance with 6-1-7/9.3.

2 Dielectric strength test in accordance with 6-1-7/9.5 and the Table below.

3 Protective device tripping test, such as overcurrent tripping, emergency tripping, preferential tripping, etc.

4 Inspection of the assembly, including inspection of wiring and, if necessary, electrical operation test.

Standard Test Voltage for Dielectric Strength Test

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Dielectric Test
Rated Insulation Voltage Voltage AC rms

Up to and including 12 V 250 V

over 12 V to 60 V inclusive 500 V

over 60 V to 300 V inclusive 2000 V

over 300 V to 690 V inclusive 2500 V

over 690 V to 800 V inclusive 3000 V

over 800 V to 1000 V inclusive 3500 V

over 1000 V to 1500 V inclusive* 3500 V

Note: *For Direct-current (DC) only

TABLE 7
Clearance and Creepage Distance for Switchboards, Distribution Boards,
Chargers, Motor
Control Centers and Controllers (1) [See 6-1-7/9.9.6]

Rated insulation voltage (V) Minimum clearances mm (in.) Minimum creepage distances mm (in.)

Up to 250 15 (19/32) 20 (25/32)

From 251 to 690 20 (25/32) 25 (1)

Above 690 25 (1) 35 (13/8)

Notes:

1 The values in this table apply to clearances and creepage distances between live parts as well as between live
parts and exposed conductive parts, including earthing.

2 For 1 kV to 15 kV systems, see 4-3-5/1.1.3.

TABLE 8
Equipment and Instrumentation for Switchboard [See 6-1-7/9.13.4]

Instrumentation and
Equipment Alternating-current (AC) Switchboard Direct-current (DC) Switchboard

1. Pilot Lamp A pilot lamp for each generator connected A pilot lamp for each generator connected
between generator and circuit breaker. See between generator and circuit breaker.
Note 3.

2. Generator A generator switch or disconnecting links in A generator switch, or disconnecting links, in

Disconnect series with the generator circuit breaker series with the circuit breaker which will
which is to disconnect completely all leads of open positive, negative, neutral and equalizer
the generator and the circuit breaker from the leads, except that for 3-wire generators,
buses, except the earth lead. See Note 1. equalizer poles may be provided on the
circuit breaker. For 3-wire generators, the
circuit breakers are to protect against a short
circuit on the equalizer buses. See Note 1.

3. Field Rheostat A field rheostat for each generator and each A field rheostat for each generator. See Note
exciter. See Note 2. 2.

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Instrumentation and
Equipment Alternating-current (AC) Switchboard Direct-current (DC) Switchboard

4. Insulation A means for continuously monitoring the A means for continuously monitoring the
Monitor and electrical insulation level to earth, and an electrical insulation level to earth, and an
Alarm audible or visual alarm for abnormally low audible or visual alarm for abnormally low
insulation values. See Note 3 and 5. insulation values. For 3-wire generators, see
4-3-5/5.3. See Note 3.

5. Ammeter An ammeter for each generator with a An ammeter for each 2-wire generator. For
selector switch to read the current of each each 3-wire generator, an ammeter for each
phase. See Note 3. positive and negative lead and a center-zero
ammeter in the earth connection at the
generator switchboard. Ammeters are to be
so located in the circuit as to indicate total
generator current.

6. Voltmeter A voltmeter for each generator, with a A voltmeter for each generator with
selector switch to each phase of the generator voltmeter switch for connecting the voltmeter
and to one phase of the bus. See Note 3. to indicate generator voltage and bus voltage.
For each 3-wire generator, a voltmeter with
voltmeter switch for connecting the voltmeter
to indicate generator voltage, positive to
negative, positive to neutral, and neutral to
negative. Where permanent provisions for
shore connections are fitted, one voltmeter
switch to provide also for reading shore-
connection voltage, positive to negative.

7. Space Heater Where electric heaters are provided for Where electric heaters are provided for
Pilot Lamp generators, a heater pilot lamp is to be fitted generators, a heater pilot lamp is to be fitted
for each generator. for each generator.

8. Synchroscope or A synchroscope or synchronizing lamps with Not applicable.

Lamps selector switch for paralleling in any
combination. See Note 3.

9. Prime mover Control for prime mover speed for Not applicable.
Speed Control paralleling. See Note 3.

10. Wattmeter Where generators are arranged for parallel Not applicable.
operation, an indicating wattmeter is to be
fitted for each generator. See Note 3.

11. Frequency A frequency meter with selector switch to Not applicable.

Meter connect to any generator. See Note 3.

12. Field Switch A double-pole field switch with discharge Not applicable.
clips and resistor for each generator. See
Note 2.

13. Voltage A voltage regulator. See Note 3. Not applicable.

Regulator

14. Stator Winding For alternating current propulsion generator For direct current propulsion generator above
Temperature above 500 kW, a stator winding temperature 500 kW, an interpole winding temperature
Indicator indicator is to be fitted for each generator indicator is to be fitted for each generator
control panel. See Notes 3 and 4. control panel. See Notes 3 and 4.

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Notes:

1 The switch or links may be omitted when draw-out or plug-in mounted generator breakers are furnished.

2 For generators with variable voltage exciters or rotary amplifier exciters, each controlled by voltage-regulator
unit acting on the exciter field, the field switch, the discharge resistor and generator field rheostat may be
omitted.

3 Where units have centralized control systems in accordance with Part 4, Chapter 9 of the ABS Marine Vessel
Rules and the generators can be paralleled from the centralized control station, and the switchboard is located
in the centralized control station, this equipment may be mounted on the control console. See 6-1-7/9.13.4.

4 For high voltage systems, see also 6-1-7/15.3.1(c).

5 For high voltage systems, see 4-3-5/1.3.5.

TABLE 9
Temperature Rise for Transformers* [See 6-1-7/11.3]

Insulation Class Average Winding-Temperature Rise Limits at Rated

Current, °C (°F)

A (105) 55 (99)

E (120) 70 (126)

B (130) 75 (135)

F (155) 95 (171)

H (180) 120 (216)

200 130 (234)

220 145 (261)

*Note: Temperature rises are based on an ambient temperature of 45°C (113°F). See 6-1-7/11.3

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 PART 6
CHAPTER 1
Material, Marine Equipment and Machinery Certification

SECTION 8
Fire and Safety - Equipment and Systems

1 Objective

1.1 Goals
The fire and safety equipment and systems covered in this section are to be designed, constructed,
operated, and maintained to:

Goal No. Goal

FIR 2 reduce the risk to life caused by fire.

SAFE 1.1 minimize danger to persons on board, the unit, and surrounding equipment/ installations from
hazards associated with machinery and systems.

MGMT 5.1 facilitate safe access, ease of inspection, survey, and maintenance of the unit, machinery, and
electrical systems

Materials are to be suitable for the intended application in accordance with the following goals and support
the Tier 1 goals as listed above.

Goal No. Goal

MAT 1 The selected materials’ physical, mechanical and chemical properties are to meet the design
requirements appropriate for the application, operating conditions and environment.

The goals in the cross-referenced Rules/Regulations are also to be met.

1.2 Functional Requirements

In order to achieve the above stated goals, the design, construction, installation and maintenance of fire and
safety equipment and systems are to be in accordance with the following functional requirements:

Functional Functional Requirements

Requirement No.

Fire Safety (FIR)

FIR-FR1 (SAFE) Fire-rated windows are designed and constructed to prevent them from breaking into small pieces
and flying apart in case of impact or fire.

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Functional Functional Requirements

Requirement No.

Safety Management (MGMT)

MGMT-FR1 Provide information on important fire and safety equipment and systems for traceability and
maintenance

1.3 Compliance
A unit is considered to comply with the goals and functional requirements when the applicable prescriptive
requirements are complied with or when an alternative arrangement has been approved. Refer to Part 1D,
Chapter 2.

2 General
Safety equipment and systems for which certification is required as indicated in 6-1-8/13 TABLE 1 are to
be designed, constructed, tested, certified and installed in accordance with this Chapter.

3 Fire Doors
Fire doors are to be type tested in compliance with the International Code for Application of Fire Test
Procedures (Resolution MSC.61(67)) (FTP Code). Watertight, weathertight or gas-tight doors are not
acceptable for use as a fire door, except when assessed and approved by ABS. See 5-1-1/3.17.

The manufacturer is to certify that the door complies with a standard to which the door is designed,
fabricated and tested, and to report the results of tests conducted for compliance with the FTP Code for the
fire rating required.

All fire doors are to bear a permanent marking to indicate manufacturer’s name, door model number and
the fire rating it is approved for.

5 Fire-Rated Windows
Fire-rated windows, for use in 'B' and 'A' class boundaries are to be tested in compliance with the FTP
Code. All fire rated windows are to be shatter resistant.

The manufacturer is to certify that the window complies with a standard to which the window is designed,
fabricated and tested, and to report the results of tests conducted for compliance with the FTP Code for the
fire rating required.

All fire-rated windows are to bear a permanent marking to indicate manufacturer’s name/symbol, window
model number and the fire rating it is approved for.

7 Gas-Tight Doors
Gas-tight doors are not required to be certified by ABS at manufacturer’s facility. These doors will be
accepted by the Surveyor after satisfactory installation and testing onboard the vessel. Watertight,
weathertight or fire doors are acceptable for use as a gas-tight door, provided the doors are tested for gas
tightness in the presence of ABS Surveyor with due consideration for the verification of self-closing
effectiveness, when required.

Design review for manufacturing and testing at the manufacturer of a gas-tight door is not required.

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9 Fire and Gas Detection Systems

The system components and associated visual and audible alarms are not required to be certified
individually. However, the main and auxiliary alarm and control panels of the detection system are
required to be certified in accordance with 6-1-8/TABLE 1.

Main and auxiliary alarm and control panels of the fire and gas detection systems are to be design-
approved by ABS.

The manufacturer is to certify that the system components and individual alarms complies with a
recognized standard to which the system is designed, fabricated and tested, and to report the results of tests
so conducted.

All main and auxiliary control panels are to bear a permanent marking to indicate manufacturer’s name,
and the model number of the panel.

11 Fire Pumps
Main and emergency fire pumps as well as other pumps used for fixed fire-extinguishing systems are to be
certified in accordance with the 6-1-8/TABLE 1 and the following. For further details, refer to 6-1-6/7.3.2
of these Rules.

Design review for manufacturing and fire extinguishing pumps is not required.

The manufacturer is to certify that the fire pump complies with a recognized standard to which the pump is
designed, fabricated and tested, and to report the results of tests so conducted.

All pumps used for fire extinguishing are to bear a permanent marking to indicate manufacturer’s name,
the model number of the pump, and its capacity.

13 Survey and Certification

Where required, type-testing and unit certification is to be carried out, in presence of and to the satisfaction
of the Surveyor, at manufacturer’s plant and reported upon before installation onboard. 6-1-8/TABLE 1
shows the extent of services required for each fire and safety equipment. Where a product does not require
unit certification, Surveyor attendance is optional, and the product is to be designed and fabricated to
satisfy a recognized industrial standard and the manufacturer’s specification.

TABLE 1
Certification Details - Safety Equipment and Systems

Safety Equipment and Systems ABS Type Rule Reference

Approval Tier

Fire doors (1) 3 6-1-8/3

Fire-rated windows(1) 3 6-1-8/5

Fire and gas detection system alarm and control panels 2 6-1-8/9

Main and emergency fire pumps, other pumps used for fixed fire- 4/5 6-1-6/7.3.2
extinguishing systems

Fixed fire extinguishing system components 2 5-2-3/1

Clean agent fire extinguishing system components 2 5-2-3/8

Helicopter deck DIFFS components 2 5-2-3/9.3.5

Fireman’s outfit(1) 3 5-2-4/3

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Safety Equipment and Systems ABS Type Rule Reference

Approval Tier

Fire hoses(1) 3 5-2-2/1.5.2

Portable and semi-portable fire extinguishers(1) 3 5-2-4/1

Note: 1. Type approval by flag Administration is acceptable in lieu of ABS Tier requirements.

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 PART 6
CHAPTER 1
Material, Marine Equipment and Machinery Certification

SECTION 9
Jacking and Associated Systems

1 Objective

1.1 Goals
The jacking and associated systems covered in this section are to be designed, constructed, operated, and
maintained to:

Goal No. Goal

SAFE 1.1 minimize danger to persons on board, the unit, and surrounding equipment/ installations from
hazards associated with machinery and systems.

AUTO 3 have an alternative means to enable safe operation in the event of an emergency or failure of
remote control.

AUTO 4 provide the equivalent degree of safety and operability from a remote location as those provided
by local controls.

AUTO 5 provide a safety system that shall automatically lead machinery controlled to a fail-safe state in
response to a fault which may endanger the safety of persons on board, machinery/equipment, or
the environment.

Materials are to be suitable for the intended application in accordance with the following goals and support
the Tier 1 goals as listed above.

Goal No. Goal

MAT 1 The selected materials’ physical, mechanical and chemical properties are to meet the design
requirements appropriate for the application, operating conditions and environment.

MAT 2 The manufacturing process is to be capable of producing products with sufficient quality and
consistent physical, mechanical and chemical properties to meet the design assumptions and to
prevent premature failure.

The goals in the cross-referenced Rules/Regulations are also to be met.

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1.2 Functional Requirements

In order to achieve the above stated goals, the design, construction, installation and maintenance of the
jacking and associated systems are to be in accordance with the following functional requirements:

Functional Functional Requirements

Requirement No.

Safety of Personnel (SAFE)

SAFE-FR1 The jacking system is to provide sufficient redundancy to prevent uncontrolled descent upon failure
of any one component.

SAFE-FR2 Gear system alignment are to be installed and maintained within design limits throughout equipment
(MGMT) life to enable proper functioning of the jacking system.

SAFE-FR3 Brakes are to perform fail-safe engagement and secure holding for the specific conditions necessary
to achieve the holding capacity.

SAFE-FR4 The flexible shock pads are to endure severe storm loads, and withstand marine and working
environment degradation.

Automation (AUTO)

AUTO-FR1 Critical and essential items are to be alarmed and displayed at a central jacking control station to
protect against failure through preventive measures

AUTO-FR2 Provide independent means of shutdown for jacking system operation in an emergency at the central
jacking control station and at each jack house.

AUTO-FR3 Provide an override option to prevent the jacking system from being locked out when the sensing
device for fixation system disengagement fails.

AUTO-FR4 Provide means to identify and rectify discrepancies in rack phase alignment where necessary to
avoid potential collapse or failure of the structure being supported.

AUTO-FR5 Provide remote control at a centralized location for coordinated operations of the jacking and
holding except permanent fixation and redundant controls in case of failure of the remote control.

Materials (MAT)

MAT-FR1 The material and components for jacking system, holding mechanism, and associated systems are to
withstand the maximum working stresses without any deformation or fatigue failure.

MAT-FR2 The material elongation for the load bearing / torque transmitting components is to be sufficiently
high so that it can withstand accidental shock or impact loads during service.

The Functional Requirements in the cross-referenced Rules/Regulations are also to be met.

1.3 Compliance
A unit is considered to comply with the goals and functional requirements when the applicable prescriptive
requirements are complied with or when an alternative arrangement has been approved. Refer to Part 1D,
Chapter 2.

2 General
Jacking systems are used to elevate and lower the hull of self-elevating units in the elevated condition and
to raise and lower the legs in the afloat condition.

The hull of the unit is maintained stationary in the elevated condition by means of a holding mechanism.
The same mechanism is used to maintain the legs stationary in the afloat condition.

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The jacking system and holding mechanism on self-elevating units are to be designed and constructed with
sufficient redundancy so that upon failure of any one component, the system will prevent an uncontrolled
descent of the unit. This is to be accomplished either by continuing to jack to a safe position or holding in
place. Approved procedures are to be provided to allow emergency raising or lowering of the unit after
failure in case the unit is holding in an unsafe position.

Jacking systems are to be considered as machinery to provide the vertical movement of the legs as well as
structural elements transmitting the loads between hull and legs, as applicable to the particular system
design.

3 Definitions
The following definitions apply for the purpose of this Section.

3.1 Jacking System

A mechanical system used for raising the hull of a self-elevating unit above the surface of the sea by
simultaneously applying a downward force on the movable legs of the unit. The same system is used for
lowering the hull from the elevated condition in a controlled manner and for raising and lowering the legs
relative to the hull in the afloat condition. The most commonly used jacking systems are the rack and
pinion type and the yoke and pin type.

3.3 Holding Mechanism

A mechanism used for maintaining the hull of a self-elevating unit stationary in the elevated condition
and/or maintaining the legs of the unit stationary in the afloat condition. The holding mechanism may be
either the jacking system in a static position or a separate fixation system or a combination of both.

3.5 Rack and Pinion Jacking System

A jacking system using climbing pinions, most commonly driven by electric or hydraulic motors through a
jacking gearbox, to engage with racks attached to the legs of the unit in order to raise or lower the hull in
relation to the legs in the elevated condition or to raise or lower the legs in relation to the hull in the afloat
condition.

3.7 Yoke and Pin Jacking System

A jacking system using yokes with pins, both operated by hydraulic cylinders, to engage with holes on the
legs of the unit in order to raise or lower the hull in relation to the legs in the elevated condition or to raise
or lower the legs in relation to the hull in the afloat condition.

3.9 Fixation System

A holding mechanism, independent from the jacking system, using a device attached to the hull to engage
a counterpart device in the legs in order to establish a rigid connection between the hull and the legs of the
unit.

3.11 Specified Service Temperature

Minimum atmospheric temperature identified for the unit (see 3A-1-1/25 and 3A-1-2/1) and documented
in the Unit's Operations Manual as per 1B-2-3/1 of the ABS Rules for Conditions of Classification –
Offshore Units (Part 1B)

3.13 Jacking Unit Rated Capacity

Vertical effective force delivered to the leg by the jacking system per jacking unit when raising or lowering
the hull. Effective force is inclusive of all frictional effects directly related to the jacking unit including leg
interfaces such as a rack and pinion mesh.

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3.15 Lifting Capacity per Leg

Vertical force per leg by the combination of jacking units attached to the leg, including the leg guide
friction effect.

3.17 System Integrator

The role of the system integrator is to be filled by the yard unless an alternative organization is specifically
contracted for or assigned this responsibility. The system integrator is responsible for the integration of
systems and products provided by suppliers into the system according to the requirements specified herein
and for providing the integrated system. The system integrator may also be responsible for integration of
systems in the unit.

5 Plans and Data to be Submitted

The following plans and data are to be submitted for the jacking and associated systems, as applicable:

i) A description of the jacking system, holding mechanism and associated systems

ii) Failure Modes and Effects Analysis (FMEA)
iii) Design plans showing the following arrangements and details, as applicable:

● Jacking system, including mechanical and hydraulic components such as rack and pinion,
bearings, reduction gears, brakes, hydraulic power units, hydraulic cylinders, etc.
● Fixation system
● Jack case (fixed or floating frame)
● Electric system diagrams
● Jacking motor and brake specifications and operating characteristics
● Electric and/or hydraulic controls
● Monitoring and alarm systems
● Lubrication methods
● Heating arrangements for low temperature operation
iv) Material specifications
v) Design calculations, including strength, fatigue, buckling, rigidity and critical speed (resonance)
analyses, as applicable to the particular system
vi) Specified service temperature
vii) Limits of alignment/misalignment between rack and pinions
viii) Motor Information:

● Design documentation
● Confirmation of application to jacking service
● Shaft design documentation (including materials) for brake arrangements subjecting shaft to
normal and/or storm holding loads while brake is engaged
ix) Brake documentation:

● Design documentation including brake static and dynamic capacities, and basis for
establishing these values
● Confirmation of application to jacking service
● Any necessary conditions for attaining specified holding capacities

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x) Specifications and documentation of computer-based control systems

xi) Technical limitations which may apply for emergency raising or lowering of the unit (such as
loads, inclination, etc.)
xii) Nondestructive examination details and procedure for inspecting components along the direct load
path including locations of inspection, types of inspection, and acceptance/rejection criteria.
Acceptance/rejection criteria is determined by the jacking gear box designer.
xiii) List of equipment that make up the jacking system along with the details of the suppliers
responsible for submitting drawings to ABS. The list is to be supported by ABS design review
letter or product design assessment (PDA) for the equipment, as applicable. When unit
certification is required for equipment or component per 6-1-9/Table 2, corresponding ABS survey
reports are to be made available to the attending Surveyor for integration of the jacking and
associated systems.

Each individual piece of equipment and/or subsystem will be issued an ABS review letter. Further, an
overall system-level review letter will be issued to the system integrator upon completion of the review of
the above plans and data.

7 Failure Modes and Effects Analysis (FMEA)

A failure modes and effects analysis (FMEA) is to be carried out on the jacking system and holding
mechanism with the purpose of demonstrating that a single failure of any component will not cause an
uncontrolled descent of the unit. The FMEA methodology has to ensure that any predictable failure mode
relevant to the purpose of the FMEA has been considered and is to be sufficiently detailed to cover all
systems associated with the jacking and holding operations. The FMEA is to be submitted for review and
is to include but not be limited to the following information:

● A description of all the systems associated with the jacking and holding operations of the unit and a
functional block diagram showing their interaction with each other. Such systems include the jacking
systems, the fixation systems, jack case, electrical power distribution system, hydraulic power system,
control systems (including programmable systems and their physical components such as
programmable logic controllers, network hubs, cards, buses, cabling, encoders, and interfaces/
displays), monitoring and alarm systems, etc. and their subcomponents.
● All significant failure modes relevant to the purpose of the FMEA
● Each predictable cause associated with each failure mode
● The method of detecting that the failure has occurred
● The effect of the failure upon the rest of the system’s ability to jack the unit, including time effects
(i.e., if necessary time is available for manual intervention)
● An analysis of possible common failure modes

Where parts of the system are identified as non-redundant and where redundancy is not possible, these
parts are to be further studied with consideration given to their reliability and mechanical protection. The
results of this further study are to be submitted for review.

9 Material
The material specifications for the components of the jacking system, holding mechanism and associated
systems including structural load carrying components (such as rack and jack case for rack and pinion
units or jacking pins and yoke for hydraulically actuated units), torque transmitting parts (such as climbing
pinion, gears, pinions, planet carriers, pins, shafts, torque supports, couplings, coupling bolts, shafts, torque
flanges and brakes of rack and pinion units), fixation system components and hydraulic components (such
as hydraulic cylinders and actuators), as applicable to the particular system design, are subject to approval
and are to be submitted by the designer. These specifications are to include as a minimum, chemical

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composition, yield strength, ultimate tensile strength, percent elongation and reduction of area, and
hardness for gears and coupling teeth, and where required, impact values.

Load bearing or torque transmitting components in the direct load path are to be constructed of steel, with
elongation and reduction in area properties in accordance with Chapter 3 of the ABS Rules for Materials
and Welding (Part 2). Subject to ABS technical assessment and approval, high strength case hardened
gears made to recognized standards may have a minimum elongation value of 8%. Other acceptable ductile
materials can be applied provided they have a minimum elongation of not less than 12%. Other materials
suitable for the intended purpose are subject to ABS technical assessment and approval.

Note:

Materials for bushing, shim plates and other components under compressive loads only need not be ductile.

Materials for the load-bearing components of the fixation system in the direct load path are to comply with
3A-1-4/5.5 and 3A-1-4/5.7, as applicable. However for fixation systems that are not of welded
construction, or are constructed from forgings or castings, the minimum required Charpy values for steel
load-bearing components are to be in accordance with 6-1-9/TABLE 1.

Material manufacturers are to be ABS approved in accordance with Chapters 1 to 3 of the ABS Rules for
Materials and Welding (Part 2). The approval scope is to include all heat treatment facilities used by the
manufacturer in the production of jacking components. For initial new production processes of the
following direct load path components: jacking pins, pinions, planet carriers, gears, shafts, torque plates,
torque couplings and torque transmitting jack casing, each manufacturer is to submit a production process
plan to ABS prior to commencing production. This can be done in the format of a manufacturing
inspection procedure (MIP), and/or an inspection and testing procedure (ITP). The manufacturers are to
demonstrate to the satisfaction of the attending Surveyor, by first article testing, that actual products meet
the mechanical properties required by the design. This is to be done by sacrificing a sample product or
extracting a sample from an actual product.

To establish correct tempering temperatures, heat treatment sensitivity studies are to be carried out to
demonstrate the tempering range where tensile, ductility and toughness are optimized. Data from the
sensitivity studies is to be submitted to ABS. Alternatively, supporting data of existing heat treatment
processes with satisfactory mechanical test results can be submitted in lieu of sensitivity studies.

Chemistry additions, forging and casting processes, and heat treatment practices are to be controlled, to
avoid detrimental microstructures and precipitates that may degrade the mechanical properties of the
material.

9.1 Toughness
The following toughness requirements refer to the core material after all thermal treatments.

For rack and pinion units, steel for the rack and rack attachments and the frame which attaches to the hull
structure is to meet the toughness requirements for primary application (see 3A-1-4/5.3.2) at the specified
service temperature in accordance with 3A-1-4/5.5 and 3A-1-4/5.7, as applicable to the steel grade. Steel
for the frame which will be used in cases of floating jacking systems is to meet the toughness criteria for
secondary application (see 3A-1-4/5.3.3) at the specified service temperature.

For systems actuated by hydraulic cylinders, steel for jacking pins and yoke is to meet the toughness
criteria for primary application (see 3A-1-4/5.3.2) at the specified service temperature in accordance with
3A-1-4/5.5 and 3A-1-4/5.7, as applicable to the steel grade.

Steel for torque transmitting parts for rack and pinion units is to meet the Charpy V Notch (CVN) impact
requirements in 6-1-9/TABLE 1. Charpy tests on forgings can be taken in the transverse or longitudinal
direction. The longitudinal and transverse forging directions are to be determined by the forge and
recorded in supporting documentation.

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Materials other than steel are to exhibit fracture toughness which is satisfactory for the intended
application, as evidenced by previous satisfactory service experience or appropriate toughness tests.

TABLE 1
Charpy V-Notch (CVN) Impact Requirements for Steel Materials

Application Charpy V-Notch (CVN) Minimum Average Values at Specified Service Temperature
(SST)

Forgings Forgings Tangential Castings

Longitudinal CVN CVN Test
Test

J kgf-m ft-lbf J kgf-m ft-lbf J kgf-m ft-lbf

Climbing Pinion and Planetary 27 2.8 20 20 2.0 15 20 2.0 15

Carriers

Low Speed Gears and Pinions 20 2.0 15 15 1.5 11 15 1.5 11

(1)

Fixation System(3) 34 3.5 25 24 2.4 17 24 2.4 17

(2)
Other SST of -20° C (-4° F) and above
Not Required

SST below -20° C (-4° F)

Subject to ABS technical assessment and approval

Notes:

1 As defined in 6-1-9/11, mesh rate MR < 100 Teeth / Minute

2 Torque transmitting / load bearing components in the load path (other than climbing pinion, planetary carriers
and low speed gears and pinions), such as high-speed pinions and gears, planetary ring gears, torque supports,
shafts, pins, couplings and coupling bolts.

3 Forging requirement applies for un-welded plate.

11 Strength Analysis

11.1 Conditions to be Analyzed

Strength calculations of the jacking system and holding mechanism are to be submitted in accordance with
6-1-9/5. Strength calculations are to consider at least the maximum loads of the following loading
conditions, as applicable to the unit:

● Normal raising of hull

● Normal holding of hull
● Normal lowering of hull
● Pre-load raising
● Pre-load holding
● Pre-load lowering
● Normal raising of legs
● Normal holding of legs
● Normal lowering of legs

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● Severe storm holding (elevated or afloat)

Maximum rated loads associated with the normal jacking, pre-load jacking and normal holding conditions
may be considered as static loadings only, where the static loads include operational gravity loadings and
weight of the unit, with the unit afloat or resting on the sea bed in calm water. Maximum rated loads
associated with severe storm conditions (elevated or afloat) and pre-load holding condition are to be
considered as combined loadings, where the applicable static loads are combined with relevant
environmental loadings, including acceleration and heeling forces.

When establishing the loads imposed on a jacking system during lifting operations for the purpose of
providing loading guidance in the operations manual required in Section 1B-2-3 of the ABS Rules for
Condtions of Classification - Offshore Units (Part 1B), friction losses are to be considered as defined in
3-2-3/9.

11.3 Strength
11.3.1 Individual Stresses
For the purpose of strength calculation of the jacking system and for designing mechanical
components (including pins), the stress is not to exceed Fy/F.S. where:

Fy = specified minimum yield point or yield strength, as defined in Chapter 1 of the ABS
Rules for Materials and Welding (Part 2)
F.S = factor of safety
.
For static loadings, as defined above:
= 1.67 for axial or bending stress
= 2.50 for shear stress
For combined loadings, as defined above:
= 1.25 for axial or bending stress
= 1.88 for shear stress

except that gear reducers are to comply with a recognized standard such as American Gear
Manufacturers Association (AGMA) standards or ISO. Gear rating calculations and justification
of the applied gear design coefficients in accordance with the applicable design standard are to be
submitted to ABS for review.

Alternative design methods for low speed gears with a mesh rate MR less than 100 teeth/minute
(where MR = RPM x Number of teeth) are subject to ABS technical assessment and approval
based on the submission of adequate evidence to validate the design method, such as first
principles calculations, experimental data and satisfactory operation experience for the intended
application. The alternative design methods are to take into account all the various degradation
factors, such as dynamic factor, non-uniform load distribution or misalignment.

11.3.2 Von Mises Approach

When recognized standards are not applicable, structural and mechanical components may be
designed according to the von Mises equivalent stress criterion. Except for components under
compressive loads only, the equivalent stress is not to exceed Fy/F.S. where:

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Fy as defined in 6-1-9/11.3.1
F.S = 1.43 for static loading, as defined in 6-1-9/11.3.1
.
= 1.11 for combined loading, as defined in 6-1-9/11.3.1
11.3.3 Fixation System
The scantlings of the load-bearing components of the fixation system in the direct load path are to
be determined on the basis of the allowable stresses specified in 6-1-9/11.3.1 or 6-1-9/11.3.2.

11.5 Buckling
As applicable to the design, the buckling strength of structures is to be verified according to the latest
version of the ABS Requirements for Buckling and Ultimate Strength Assessment for Offshore Structures,
or other recognized standard acceptable to the ABS.

11.7 Fatigue
Fatigue damage of jacking system components due to cyclic loading is to be considered. A fatigue analysis
is to be performed using an appropriate loading spectrum. The fatigue analysis is to be based on
recognized fatigue assessment methodologies such as those shown in the latest editions of AGMA and ISO
gear standards or the Miner's Rule for cumulative fatigue. For gears, both tooth surface contact and tooth
root bending fatigue strength are to be considered. The calculated fatigue life is to be at least the design life
of the unit, but not less than 20 years. Safety factors against maximum fatigue life in hours or cycles are to
be as follows:

1. Tooth root bending: F.S. = 1.5 for cumulative fatigue due to all lifting and lowering
operations and all other applicable cyclic loads
2. Tooth surface contact: F.S. = 1.0 for cumulative fatigue due to all lifting and lowering
operations and all other applicable cyclic loads

In the calculation of the tooth surface contact fatigue, the magnitude/effect of non-uniform face load
distribution is to be considered. Inspectable low speed, through hardened pinions and gears may not need
to comply with the above safety factor for tooth surface contact fatigue, subject to past satisfactory
experience with material and design for this purpose.

Jacking system design may be accepted based on full life-cycle fatigue load test results in lieu of
theoretical fatigue calculations. Acceptability of test results is to be governed by the type and the extent of
the testing. When testing for fatigue, the jacking system or parts are to be subject to all the applicable
maximum cyclic loading conditions and each applicable load level is to be multiplied with relevant safety
factors. The safety factors applied in case of full life-cycle fatigue load test are subjected to ABS technical
assessment and approval.

Note:

Full-life cycle fatigue load test does not exclude the required mandatory prototype test.

Where applicable, critical speed (resonance) analysis of rotating components is to be submitted to

demonstrate that there are no harmful vibrations at operating speeds. Test results in lieu of theoretical
analysis may be considered.

11.9 Alignment
For rack and pinion systems, the alignment between the rack and pinion is to be maintained within
specified limits throughout the life of the rig. Documentation in this regard is to be submitted to the ABS.

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13 Mechanical Components
In addition to the strength requirements for mechanical components in accordance with 6-1-9/11, the
following requirements are to be complied with:

Commentary:

Recommend that a greasing system be integrated into the design to minimize wear, pollution, and personnel hazards.

End of Commentary

13.1 Bearings
Bearings are to be designed for the operational static and dynamic loads in accordance with applicable
recognized standards such as the latest editions of ISO 76 and ISO 281. Design calculations are to be
submitted for bearings not covered by recognized standards. Adequate bearing lubrication is to be
provided. Manufacturer’s documentation is to be submitted to confirm the suitability of the bearings for
operation at the design temperature of the unit.

13.3 Brakes
Brakes are to be designed to engage automatically in the event of failure of power supply to the motor
(fail-safe type). The brake holding capacity is to be at least equal to 120% of the maximum required brake
torque associated with the maximum rated load applied to the climbing pinion from all loading conditions
specified in 6-1-9/11. Brake static capacity is to be applied in holding conditions, and dynamic capacity
(i.e., ability to stop motion) is to be applied for raising and lowering conditions.

The brake manufacturer is to submit documentation identifying the static and dynamic capacities of the
brakes, the basis upon which these capacities have been established (e.g., by testing), and statement
confirming that the brakes are intended for jacking gear service. The prototype tests (holding capacity
tests) are to be witnessed by ABS. Dynamic capacity is to be established based on the operational speed of
the motor and may reflect regenerative braking if provided.

Any conditions on attaining the stated holding capacity are to be specified by the manufacturer, and are to
be included in maintenance manuals or marked on the data plate attached to the brake housing or casing.
Examples include clearance range (air gap, minimum and maximum), brake run-in procedures, maximum
ambient or operating temperature, minimum number of springs to be maintained in the brake, or maximum
number of stops in a given time period.

13.5 Flexible Shock Pads

Jack case shock pads are to be designed for the maximum severe storm loads and suitable for operation at
the design temperature of the unit. Shock pads are to be suitably protected against adverse effects of the
marine and working environment which may lead to degradation. Manufacturer’s technical specification or
similar documentation is to be submitted to verify the suitability of the shock pads for the intended service.

15 Electrical Power System

15.1 Electric Motor Drive

Jacking gear motor installations are to be in accordance with Part 4, Chapter 3, Section 6-1-7, 6-1-9/
TABLE 2, and the requirements below, Design documentation is to be submitted for all motors, with
particular attention paid to brake arrangements where the motor shaft is subject to the normal and/or storm
holding loads. Where the shaft is subject to such loads, design review and material testing of the motor
shaft are to be carried out in accordance with 6-1-9/9 under the applicable loads.

The capacity of the electric motor is to be sufficient for lifting requirements such as the following:

● Lifting the platform with uneven load (but within approved tolerances) for a specific duration;
● Lifting in preload, if specified, with a specific duration.

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The friction between legs and guides, as well as the efficiency of the gear transmissions, is to be
considered. See 6-1-9/11.1.

Group motor installations are permitted as follows:

● On each leg, two or more motors of any power may be connected to a single branch circuit.
● The branch circuit is to be provided with short circuit protection set at not greater than ten times the
sum of the full load currents of the motors.

A visual and audible alarm is to be provided at the jacking control station to indicate an overload condition
in any of the jacking motors.

The motor manufacturer is to confirm that motors are intended for jacking gear service and are rated for
operation over the required range of input voltage, current, frequency, and other parameters as applicable.
Limitations on the motor such as maximum number of starts per hour or the minimum time between starts
of the electric motors are also to be specified.

17 Hydraulic System
The hydraulic system for jacking units and holding mechanisms is to be in accordance with 4-2-6/3.
Design of hydraulic cylinders and actuators, including materials, is to be in accordance with 4-2-2/19.
Hydraulic cylinders are to be considered both as pressure containing and load bearing units.

Sufficient redundancy of the hydraulic power unit or units servicing the jacking systems is to be provided
to maintain continuous jacking operation in the event of a single failure in the hydraulic power system.

17.1 Hydraulic Motor Drive

Hydraulically driven motors used for elevating and lowering the unit are to be designed based on
applicable pressure vessel and piping standards for pressure retaining components, allowable stress for
torque components, and recognized standards for seals. As an alternative to design review, mass produced
motors may be accepted on the basis of specification review and a prototype test to 150% of the rated load,
subject to agreement on design standards and manufacturing process.

Where an integral brake is not provided, the arrangement is subject to review and testing of the motor shaft
if it is subject to normal and storm holding loads, as indicated in 6-1-9/15.1 for electric motors.

19 Control, Monitoring and Alarm System

Operation of the jacking system and holding mechanism is to be possible from a central jacking control
station, except that the operation of a fixation system is to be from a local control station in visual
proximity to the system at each leg chord. The central jacking control station is to be provided with the
following alarms and indications, as applicable to the particular system design:

i) Audible and visual alarms for:

● Motor overload, over temperature or overvoltage for each motor

● Unit out-of-level (elevated condition)
● Significant differences in the currents or torque in the motors on one rack
● Rack phase differential, where applicable to the design
● Brake fault, overload or overheating
● PLC failure
ii) Indication of:

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● Availability of power
● Current or torque in each motor (during raising and lowering operations)
● Brake release status
● Hydraulic pressure
● Air pressure
● Pin position
● Position of yoke
● Inclination of the unit, in two horizontal, perpendicular axes (elevated condition)
● Re-Torque mode
● Motor and brake fault override for each leg
● Motor heater power for each leg

Upon failure of the jacking system controls in the central control station, emergency controls to operate the
jacking system are to be available.

An emergency stop is to be provided at the central jacking control station and at each jack house.
Emergency stop circuits are to be independent from the jacking control circuits. An override of the
interlock between jacking operation and fixation system engagement is to be provided to prevent the
jacking system from being locked-out in the case of a failure of the sensing device for fixation system
disengagement. A communication system as defined in 4-3-2/15.5.4 is to be provided.

Procedures and/or arrangements for confirming engagement and full disengagement status of fixation
system are to be verified by attending Surveyor. The procedures are to be incorporated into the Operating
Manual as specified in 1B-2-4/1.17.

Arrangements are to be provided for detecting and correcting rack phase differential, where applicable to
the design.

19.1 Programmable Electronic System (PES)

Where the jacking system uses Programmable Electronic Systems as defined in 4-3-4/5 for control and/or
monitoring of jacking operations, such systems are to comply with Section 4-9-3 of the Marine Vessel
Rules. Category I or II is to be assigned based on the functionality and criticality of the Programmable
Electronic Systems. If a Programmable Electronic Systems is only used for monitoring and indication,
Category I can be assigned. If control logic operates part or all of the functions of the system, Category II
may be assigned depending on the FMEA findings.

Programmable Electronic jacking control Systems are not considered “integrated” systems for the purposes
of applying 4-9-3/5.3 of the Marine Vessel Rules.

Basic and application software for control systems are to reboot into a proven safe jacking system holding
mode.

21 Low Temperature Operation

Jacking systems, holding mechanisms and associated systems intended for operation at a specified service
temperature below -20°C (-4°F) are subject to ABS technical assessment and approval.

23 Jacking Systems of Novel Design

Jacking systems other than rack and pinion type or yoke and pin type are subject to ABS technical
assessment and approval. Compliance with this section is required, as applicable. The suitability of the
novel features is subject to ABS technical assessment and approval on the basis of first principles,

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applicable recognized standards and experimental test results, depending on the particular characteristics of
the jacking system and type of unit.

25 Survey and Certification

All jacking or other elevating systems for Self-Elevating Units are required to be certified by the attending
Surveyor before installation and onboard testing.

Electric motors intended for jacking systems are to be certified as per 6-1-7/19.1 and/or 6-1-9/15.1.

Hydraulic motors are to be functionally tested as per manufacturer’s test procedures and certified at the
manufacturer facility as per 6-1-9/17.1.

Gear box units are to be functionally tested as per manufacturer’s test procedures and certified at the
manufacturer facility. The components of the gear box are to be tested as per requirements in 6-1-9/Table
2. The accuracy of the meshing is to be verified by the attending surveyor.

25.1 Inspection and Material Testing

All jacking systems, holding mechanisms and associated systems are to be constructed and installed to the
satisfaction of the Surveyor in accordance with approved plans.

Welded construction is to be in compliance with the applicable requirements of Section 3-2-6, 7-1-2/9 and
7-1-2/11 of these Rules and Chapter 4 of the ABS Rules for Materials and Welding (Part 2). Material tests
for the components of the jacking systems, holding mechanisms and associated systems are to be carried
out in accordance with 6-1-9/9 and Chapters 1 to 3 of the above referenced Part 2. All material testing as
indicated in 6-1-9/TABLE 1 is to be witnessed by the attending Surveyor.

Gears of the climbing pinion gear train are to be examined at the plant of the manufacturer by an approved
crack detection procedure and such examination is to be witnessed by the Surveyor. For direct load path
components, the locations of inspection, types of inspection and acceptance/rejection criteria are to be
clearly indicated in the documentation. Surface and volumetric inspection is to be performed to a
recognized Standard appropriate to the process of manufacture, such as ASTM A275, A903, A388 or
A609. Acceptance criteria is to be submitted by the designer for approval. In determining the inspection
details and acceptance criteria consideration is to be given to:

i) The material type and grade (influence on crack sensitivity)

ii) The mill process (steel making processes/cleanliness, casting mold details, forging reduction ratio,
etc.) (likelihood of cracking and critical locations)
iii) Redundancy of equipment (influence on consequence of failure)
iv) The stage of manufacturing*
v) In-service local high stress concentrations
vi) The anticipated in-service fatigue loading
vii) Product size
viii) Type of defect, longitudinal or rounded
ix) Cracks produced during secondary processing (forging, welding, heat treatment or surface
hardening)
Note: * Where ultrasonic testing is specified for direct load path components, it is more effective to UT basic shapes than
to UT a finished component containing complex profiles, shapes, or details.

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25.1.1 Heat Treatment

All test specimens are to be representative of the components in the jacking system and in
accordance with Chapter 3 of the above referenced Part 2. Representative specimens are to be of
the same material grade, from the same heat and heat treatment batch, and are to be of sufficient
size and mass to represent the heat transfer experienced in the components themselves during the
complete heat treatment cycle.

Components and test material are to be heat treated together in the same furnace, and quenched in
the same bath/tank (for Q & T components).

25.1.2 Surface Hardening

Where it is intended to surface harden climbing pinion teeth, full details of the proposed procedure
and specification are to be submitted for approval. The manufacturer/heat treater is required to
demonstrate by test that the proposed procedure gives a uniform surface layer of the required
hardness and depth and that it does not impair the soundness and properties of the steel. Test
specimens are to be representative of the climbing pinion and in accordance with Chapter 3 of the
above referenced Part 2. Representative specimens are to be of the same material grade, from the
same heat and heat treatment batch, and are to be of sufficient size and mass to represent the heat
transfer experienced in the pinions themselves during the complete heat treatment cycle, including
the surface hardening cycle.

For other surface hardened gearing, recognized national or international standards are to be
applied.

25.3 Prototype Test

A prototype test is to be performed on one unit of a newly designed rack and pinion system as part of the
design approval procedure. The prototype testing and examination is to be carried out in the presence of,
and to the satisfaction of, the Surveyor.

The prototype test procedure is to be submitted for review and as a minimum is to include the following:

i) It is to be confirmed that the prototype has been manufactured to similar processes and materials,
and according to the approved material specification, as that applied for the production units.
ii) Prior to the prototype test, all pinions and gears of the climbing pinion gear train are to be
examined using an approved crack detection procedure. (ABS material certificates as per
6-1-9/25.1 are to be provided for the prototype unit.)
iii) The prototype test is to be carried out at 150% of the maximum normal holding capacity rating of
the unit. As a minimum, the test is to be carried out for one complete revolution of the climbing
pinion.
iv) Subsequent to the prototype test, the unit is to be disassembled and examined. All pinions and
gears of the climbing pinion gear train are to be examined using an approved crack detection
procedure.

25.5 Replacement Jacking Equipment for Units in Operation

The following requirements apply to all jacking components, rack fixation systems, and associated
equipment.

25.5.1 Design
Replacement components may be fabricated using original designs that were accepted in
accordance with the same or earlier Rules.

Replacement components may be fabricated in accordance with designs approved to Rules more
recent than the unit’s contract date.

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25.5.2 Material and Heat Treatment

Material manufacturers are to be ABS approved in accordance with Chapters 1 to 3 of the ABS
Rules for Materials and Welding (Part 2).

The approval scope is to include all heat treatment facilities used by the manufacturer in the
production of jacking components.

Replacement components may be fabricated using original material specifications, or to

specifications accepted by ABS engineering department.

25.5.3 Fabrication and testing

Components are to be fabricated to the satisfaction of the attending Surveyor in accordance with
the following requirements:

i) Inspection and material testing is to be conducted in accordance with 6-1-9/25.1 Testing

is to include the following items:
a) Physical/mechanical properties:
● Yield strength
● Ultimate tensile strength
● Percent elongation
● Reduction of area
● Charpy Impacts
– Are to be taken in locations specified by 6-1-9/9.1
– Values are to be in accordance with the design
● Hardness Values
b) Nondestructive Testing (NDE) Requirements
25.5.4 Installation
Certification conducted for components using this section will only be valid for use on units with a
contract date the same as or previous to the elevating system’s design approval date.

25.5.5 Reconditioning of Existing Equipment

Existing equipment removed from a unit Classed with ABS may be reconditioned and used as
replacement equipment on a unit with the same Rule requirements.

All existing components that are reconditioned or repaired by welding are to have the testing listed
above conducted were applicable.

Weld procedures are to be qualified by using actual components and tested in accordance with the
complete list above.

TABLE 2
Certification Details – Jacking and Associated Systems(1,3)

Jacking and Associated Systems Material NDE Functional/ ABS Type Rule
Certification Load test Approval Reference
Tier
Material of load carrying components
Rack and jack-case for rack and pinion units X X - 5 6-1-9/9

Jacking pins and yoke for hydraulic actuated units X X - 5 6-1-9/9

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Jacking and Associated Systems Material NDE Functional/ ABS Type Rule
Certification Load test Approval Reference
Tier

Material of torque transmitting parts

Climbing pinion X X - 5 6-1-9/9

Gears X X - 5 6-1-9/9

Pinions X X - 5 6-1-9/9

Planetary carriers X X - 5 6-1-9/9

Pins X X - 5 6-1-9/9

Shafts X X - 5 6-1-9/9

Torque Supports X X - 5 6-1-9/9

Torque flanges X X - 5 6-1-9/9

Couplings X X - 5 6-1-9/9

Couplings bolts X X - 5 6-1-9/9

(2)
Jacking Gear Motor shafts (regardless of Motor X X - 5 6-1-9/9,
rating) when integral to braking or in the load path 6-1-9/15.1

Holding mechanism (e.g., fixation system) X X - 5 6-1-9/9

components in the load path

Assembled Gear Box Unit - - X 5 6-1-9/25

Assembled Hydraulic Power Units - - X 5 6-1-9/17

Brakes - - - 2 6-1-9/13.3

Bearings - - - 1 6-1-9/13.1

Flexible shock pads - - - 2 6-1-9/13.5

Electric motors >100 kW (135 hp) - - X 5 6-1-7/19.1 and

6-1-9/15.1

Electric motors ≤ 100 kW (135 hp) - - - 2 6-1-9/15.1

Hydraulic jacking motors - - X 4/5 6-1-9/17.1

Hydraulic system components in the load path, for - - X 5 6-1-9/17

jacking unit and holding mechanism, including
hydraulic cylinders and actuators

Hydraulic system components of standard design - - - 1 6-1-9/17

not in the load path, for jacking unit and holding
mechanism, including hydraulic cylinders and
actuators

Hydraulic system components of non-standard - - - 2 6-1-9/17

design not in the load path, for jacking unit and
holding mechanism, including hydraulic cylinders
and actuators

System control, monitoring and alarms - - X 5 6-1-9/19

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Notes:
1 All jacking and associated systems are to comply with 6-1-9/25.
2 ABS to witness a hardness test only at accessible location on the motor shaft, to verify hardness is within
manufacturer specification. Other mechanical tests and NDE need not be ABS witnessed.
3 Components need not be individually design approved/ type approved if they are part of an assembly that is type
approved.

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 PART 6
CHAPTER 1
Material, Marine Equipment and Machinery Certification

SECTION 10
Mooring Systems and Equipment

1 Objective

1.1 Goal and Functional Requirements

The goals and functional requirements in the cross-referenced Rules are to be met.

1.2 Compliance
A unit is considered to comply with the Goals and Functional Requirements when the applicable
prescriptive requirements are complied with or when an alternative arrangement has been approved. Refer
to Part 1D, Chapter 2.

2 General
This Section applies to offshore units that are classed with the Ⓔ, Ⓜ, Ⓟ, TAM, TAM-R, TAM (Manual),
P-PL, M-PL, TAM-PL or TAM-PL(Manual) symbol and also self-propelled units that are required to
have temporary mooring equipment in Section 3-4-1 that have no symbol.

Additional requirements for offshore units that are classed with the optional Ⓜ, Ⓟ, TAM, TAM-R, TAM
(Manual), P-PL, M-PL, TAM-PL or TAM-PL(Manual) symbols are located in Appendix 7A-1-9.

Site-specific units to which the ABS Requirements for Position Mooring Systems are applicable are to
comply with this Section.

Design, construction and installation of all windlasses used for anchoring (temporary mooring) are to be
carried out in accordance with 4-1-1/5 and Section 4-5-1 of the Marine Vessel Rules.

3 Temporary Mooring Equipment

All anchoring equipment required for temporary mooring is to be fabricated and tested in presence of and
to the satisfaction of the attending Surveyor, and certified in accordance with 6-1-10/9 TABLE 1 and
6-1-10/9 TABLE 2.

For non-propelled units fitted with an anchoring (temporary mooring) equipment, if the optional symbol Ⓔ
is requested, equipment is to be fabricated and tested in presence of and to the satisfaction of the attending
Surveyor, and certified in accordance with 6-1-10/3.1 and 6-1-10/9 TABLE 1.

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For self-propelled offshore units, if the optional symbol Ⓔ* is requested, equipment is to be tested in the
presence of a Surveyor in accordance with the specifications of the Owner and in accordance with
6-1-10/3.3, 6-1-10/5 and 6-1-10/9 TABLE 2.

3.1 Inspection and Material Testing

All equipment for Ⓔ is to be constructed and installed to the satisfaction of the Surveyor in accordance
with approved plans.

Material and testing for anchors are to be in accordance with the requirements of Chapter 2 of the ABS
Rules for Materials and Welding (Part 2) for the respective sizes of anchors. Material tests for the
components of the anchoring system are to be carried out in accordance with Chapters 2 to 3 of the above
referenced Part 2. All material testing is to be witnessed by the attending Surveyor.

Welded construction is to be in compliance with the applicable requirements of Section 3A-2-6, 7A-1-2/9
and 7A-1-2/11 of these Rules and Chapter 2 of the ABS Rules for Materials and Welding (Part 2).

All equipment is to be examined at the plant of the manufacturer by an approved crack detection procedure
and such an examination is to be witnessed by the Surveyor. Acceptance of components manufactured at a
plant which is under an ABS approved quality assurance program are subject to ABS technical assessment
and approval.

3.3 Prototype Testing of Anchor Windlass

For units without Ⓔ, a prototype test is to be performed on one unit of a newly designed anchor windlass
in lieu of the design approval procedure. The prototype testing and examination is to be carried out in the
presence of, and to the satisfaction of, the Surveyor.

5 Survey and Certification of Position Mooring Equipment Ⓜ or M-PL

All equipment is to be constructed in accordance with the owner’s specifications. All material testing is to
be witnessed by the attending Surveyor. See 6-1-10/9 TABLE 3. For a mooring system with M-PL
Notation, pre-laid mooring is not part of ABS scope of certification.

7 Survey and Certification of Position Mooring Systems Ⓟ or P-PL

Mooring systems for units with the symbol Ⓟ or P-PL are to be constructed and tested in the presence of a
Surveyor in accordance with the drawings reviewed by ABS. For a mooring system with P-PL Notation,
pre-laid mooring is not part of ABS scope of certification.

For testing of materials intended for component construction see 6-1-10/9 TABLE 4.

Welding is to be in accordance with ABS Rules for Materials and Welding (Part 2).

Each component that requires to be certified by 6-1-10/9 TABLE 4 is to be inspected during manufacture
by a Surveyor for conformance with the design approved.

9 Survey and Certification of Position Mooring Systems TAM, TAM-R,

TAM (Manual), TAM-PL or TAM-PL(Manual)
Mooring systems for units with the symbol TAM, TAM-R, TAM (Manual), TAM-PL or TAM-
PL(Manual) are to be designed, constructed, certified and installed in accordance with the provisions of
this section. For a mooring system with TAM-PL or TAM-PL(Manual) Notation, pre-laid mooring is not
part of ABS scope of certification.

For testing of materials intended for component construction see 6-1-10/9 TABLE 5.

Welding is to be in accordance with the ABS Rules for Materials and Welding (Part 2).

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Each component that is required to be certified by 6-1-10/9 TABLE 5 is to be inspected during

manufacture by a Surveyor for conformance with the design approved.

TABLE 1
Certification Details - Temporary Mooring Equipment
with Ⓔ Symbol

Equipment ABS Approval Tier Rule Reference

1. Anchor windlass(4) 4/5 6-1-10/1, 6-1-10/3,

6-1-10/3.1

2. Anchors(1) 5 6-1-10/3, 6-1-10/3.1

3. Anchor chains/wire-ropes(1, 2) 5 6-1-10/3, 6-1-10/3.1

4. Anchor chain accessories (Shackles/Links)(1) 5 6-1-10/3, 6-1-10/3.1

(2)
5. Anchor wire-rope accessories (Sockets/Links) 5 6-1-10/3, 6-1-10/3.1

6. Fiber Ropes(3) 5 6-1-10/3, 6-1-10/3.1

7. Fairleads and Sheaves 2 6-1-10/3, 6-1-10/3.1

8. Chain Stoppers 2 6-1-10/3, 6-1-10/3.1,

3-4-1/17.1

Notes:
1 Fabrication and Testing of components is to be in accordance with Sections 2-2-1 and 2-2-2 of the ABS Rules for
Materials and Welding (Part 2).
2 Fabrication and Testing of components is to be in accordance with API Spec 9A and API RP 9B.
3 Fabrication and Testing of components is to be in accordance with the ABS Requirements for the Application of
Fiber Ropes for Offshore Mooring.
4 Fabrication and Testing of anchor windlass is to be in accordance with Section 4-5-1 of the ABS Rules for
Building and Classing Marine Vessels.

TABLE 2
Certification Details - Temporary Mooring Equipment
without Ⓔ Symbol

Equipment (1) ABS Approval Tier (2) Rule Reference

1. Anchor windlass 5 6-1-10/1, 6-1-10/3 ,

6-1-10/3.3

2. Anchors 5 6-1-10/3

3. Anchor chains/wire-ropes 5 6-1-10/3

4. Anchor chain accessories (Shackles/Links) 5 6-1-10/3

5. Anchor wire-rope accessories (Sockets/Links) 5 6-1-10/3

6. Fiber Ropes 5 6-1-10/3

7. Fairleads and Sheaves 5 6-1-10/3

8. Chain Stoppers 5 6-1-10/3

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Notes:
1 Equipment is to be tested in the presence of a Surveyor in accordance with the specifications of the Owner and in
accordance with 6-1-10/5.
2 Design review is only required when applying for Type Approval Program. Fabrication is to be to Owner’s
specifications.

TABLE 3
Certification Details – Position Mooring Equipment for Ⓜ or M-PL Symbol

Equipment ABS Approval Tier (5) Rule Reference

(6)
1. Anchor windlass 4/5 6-1-10/5

2. Anchors (may not be applicable for M-PL)(2) 5 6-1-10/5

3. Offshore Mooring Chains/wire ropes(1, 3) 5 6-1-10/5

(1)
4. Offshore Mooring Chain accessories (shackles/links) 5 6-1-10/5

5. Anchor rope accessories (sockets/links)(3) 5 6-1-10/5

6. Fiber Ropes(4) 5 6-1-10/5

(5)
7. Fairleads and Sheaves 5 6-1-10/7

8. Chain Stoppers(5) 5 6-1-10/7

Notes:
1 Testing of components is to be in accordance with the requirements for “R” grade chain as specified in the ABS
Requirements for Certification of Offshore Mooring Chain.
2 Testing of components is to be in accordance with Section 2-2-1 of the ABS Rules for Materials and Welding
(Part 2).
3 Testing of components is to be in accordance with API Spec 9A and API RP 9B.
4 Testing of components is to be in accordance with the ABS Requirements for the Application of Fiber Ropes for
Offshore Mooring.
5 Design review is only required when applying for Type Approval Program. Fabrication is to be to Owner’s
specifications. Refer to Section 6 of the ABS Requirements for Position Mooring Systems.
6 Equipment is to be in compliance with industry standards, ABS Requirements for Position Mooring Systems (refer
to Subsection 6/11).

TABLE 4
Certification Details – Position Mooring Equipment for Ⓟ or P-PL Symbol

Equipment ABS Approval Tier (5) Rule Reference

1. Anchor windlass(6) 4/5 6-1-10/7

(2)
2. Anchors (may not be applicable for P-PL) 5 6-1-10/7

3. Offshore Mooring Chains/wire ropes(1, 3) 5 6-1-10/7

4. Offshore Mooring Chain accessories (shackles/links)(1) 5 6-1-10/7

(3)
5. Anchor rope accessories (sockets/links) 5 6-1-10/7

6. Fiber Ropes(4) 5 6-1-10/7

(5)
7. Fairleads and Sheaves 5 6-1-10/7

8. Chain Stoppers(5) 5 6-1-10/7

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Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 10 Mooring Systems and Equipment 6-1-10

Notes:
1 Fabrication and Testing of components is to be in accordance with the requirements for “R” grade chain as
specified in the ABS Requirements for Certification of Offshore Mooring Chain.
2 Fabrication and Testing of components is to be in accordance with Section 2-2-1 of the ABS Rules for Materials
and Welding (Part 2).
3 Fabrication and Testing of components is to be in accordance with API Spec 9A and API RP 9B.
4 Fabrication and Testing of components is to be in accordance with the ABS Requirements for the Application of
Fiber Ropes for Offshore Mooring.
5 Refer to Section 6 of the ABS Requirements for Position Mooring Systems.
6 Equipment is to be in compliance with industry standards, ABS Requirements for Position Mooring Systems (refer
to Subsection 6/11).

TABLE 5
Certification Details – Position Mooring System for TAM, TAM-R, TAM (Manual),
TAM-PL or TAM-PL(Manual) Symbol

Component Required for TAM, TAM-R, TAM(Manual), TAM- ABS Approval Tier (5) Rule Reference
PL, TAM-PL(Manual) Symbol

1. Anchor windlass(7) 4/5 6-1-10/9

2. Anchors (may not be applicable for TAM-PL, TAM- 5 6-1-10/9

PL(Manual))(2)

3. Offshore Mooring Chains/wire ropes(1, 3) 5 6-1-10/9

4. Offshore Mooring Chain accessories (shackles/links)(1) 5 6-1-10/9

(3)
5. Anchor rope accessories (sockets/links) 5 6-1-10/9

6. Fiber Ropes(4) 5 6-1-10/9

7. Fairleads and Sheaves(6) 5 6-1-10/7

(6)
8. Chain Stoppers 5 6-1-10/7

9. Thruster Controls System(5) 5 6-1-10/9

(5)
10. Power Controls System 5 6-1-10/9

11. DP Control System(5) 5 6-1-10/9

12. Position reference System(5) 5 6-1-10/9

(5)
13. Sensors 5 6-1-10/9

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 120
Part 6 Equipment and Machinery Certification
Chapter 1 Material, Marine Equipment and Machinery Certification
Section 10 Mooring Systems and Equipment 6-1-10

Notes:
1 Fabrication and Testing of components is to be in accordance with the requirements for “R” grade chain as
specified in the ABS Requirements for Certification of Offshore Mooring Chain.
2 Fabrication and Testing of components is to be in accordance with Section 2-2-1 of the ABS Rules for Materials
and Welding (Part 2).
3 Fabrication and Testing of components is to be in accordance with API Spec 9A and API RP 9B.
4 Fabrication and Testing of components is to be in accordance with the ABS Requirements for the Application of
Fiber Ropes for Offshore Mooring.
5 Fabrication and Testing of components is to be in accordance with the ABS Guide for Dynamic Positioning
Systems.
6 Refer to Section 6 of the ABS Requirements for Position Mooring Systems.
7 Equipment is to be in compliance with industry standards, ABS Requirements for Position Mooring Systems (refer
to Subsection 6/11).

ABS RULES FOR BUILDING AND CLASSING OFFSHORE UNITS • 2025 121