Engineering Standard

SAES-P-119 1 January 2018

Substations
Document Responsibility: Electrical Substations Equipment Standards Committee

Contents
1 Scope ................................................................ 2
2 Conflicts and Deviations ................................... 2
3 References........................................................ 2
4 Acronyms and Definitions ................................. 5
5 General ............................................................. 5
6 Substation Buildings ......................................... 8
7 Substation Yard .............................................. 12
8 Substation Bus Configurations ........................ 19
Revision Summary................................................. 21

Previous Issue: 30 July 2017 Next Planned Update: 30 July 2020

Contact: Ishwait, Basel A. (ishwaiba) on phone +966 13 880-9664 Page 1 of 21

©Saudi Aramco 2017. All rights reserved.

Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
Issue Date: 1 January 2018
Next Planned Update: 30 July 2020 Substations

1 Scope

This standard presents the mandatory requirements for the design and installation of
onshore and when specifically specified in this standard, offshore power substations.

This document may not be attached to nor made a part of purchase orders.

2 Conflicts and Deviations

2.1 If there are any conflicts between this standard and associated project or
engineering documents, this standard shall take precedence. The exception is if
an approved Waiver Request has been included with the purchasing documents.

2.2 Any conflicts between this document and other applicable Mandatory Saudi
Aramco Engineering Requirements (MSAERs*) shall be addressed to the
EK&RD Coordinator.
* Examples of MSAERs are Saudi Aramco Materials System Specifications (SAMSSs),
Engineering Standards (SAESs) and Standard Drawings (SASDs).

2.3 Any deviation from the requirements herein shall follow internal company
procedure SAEP-302.

2.4 The designation “Commentary” is used to label a sub-paragraph that contains

comments that are explanatory or advisory. These comments are not mandatory,
except to the extent that they explain mandatory requirements contained in this
SAES.

3 References

The selection of material and equipment, and the design, construction, maintenance, and
repair of equipment and facilities covered by this standard shall comply with the latest
edition of the references listed below unless otherwise noted.

3.1 Saudi Aramco References

Saudi Aramco Engineering Procedure

SAEP-302 Instructions for Obtaining a Waiver of a Mandatory
Saudi Aramco Engineering Requirement

Saudi Aramco Engineering Standards

SAES-B-014 Safety Requirements for Plant and Operations
Support Buildings
SAES-B-017 Fire Water System Design
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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
Issue Date: 1 January 2018
Next Planned Update: 30 July 2020 Substations

SAES-B-019 Portable, Mobile, and Special Fixed Firefighting

Equipment
SAES-B-055 Plant Layout
SAES-B-068 Electrical Area Classification
SAES-K-001 Design and Installation of Heating, Ventilating, and
Air Conditioning Systems
SAES-K-002 Air Conditioning Systems for Essential Operating
Facilities
SAES-M-006 Saudi Aramco General Purpose Fencing
SAES-M-009 Design Criteria for Blast Resistant Buildings
SAES-M-100 Saudi Aramco Building Code
SAES-O-Series Security Standards
SAES-P-100 Basic Power System Design Criteria
SAES-P-103 UPS and DC Systems
SAES-P-111 Grounding
SAES-P-116 Switchgear and Control Equipment
SAES-P-121 Transformers and Reactors
SAES-P-123 Lighting
SAES-P-126 Power System Automation
SAES-Q-006 Asphalt and Sulfur Extended Asphalt Concrete Paving
SAES-S-020 Oily Water Drainage Systems

Saudi Aramco Materials System Specifications

14-SAMSS-531 Power Transformers
14-SAMSS-533 Three-Phase Dry-Type Power Transformers
14-SAMSS-534 Overhead-Type Distribution Transformers
14-SAMSS-536 Pad-Mounted Three-Phase Distribution
Transformers
16-SAMSS-502 Metal-Enclosed Low-Voltage Switchgear
Assemblies
16-SAMSS-503 Indoor Controlgear - Low Voltage
16-SAMSS-504 Indoor Metal-Clad Switchgear 1 to 38 kV
16-SAMSS-506 Indoor Controlgear - High Voltage
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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
Issue Date: 1 January 2018
Next Planned Update: 30 July 2020 Substations

16-SAMSS-510 Manually Operated Pad Mounted SF6 Switchgear:

1 kV to 36 kV
16-SAMSS-514 Control and Protective Relay Panel - Indoor

Saudi Aramco Standard Drawing

AB-036319 Standard Sign: Danger High Voltage

3.2 Industry Codes and Standards

American National Standards Institute

ANSI C2 National Electrical Safety Code
ANSI/NFPA 70 National Electrical Code
IEEE Std 605-2008 IEEE Guide for Bus Design in Air Insulated
Substations
IEEE Std 979-2012 IEEE Guide for Substation Fire Protection
IEEE Std 980-2013 IEEE Guide for Containment and Control of Oil
Spills in Substations
IEEE C37.1 - 2007 SCADA and Automation Systems
IEEE 998 - 2012 IEEE Guide for Direct Lightning Stroke Shielding of
Substations

3.3 SASO Standards

SASO 2203/2003 Plugs and Socket-Outlets for Household and Similar
General Use 220 V

3.4 Saudi Electricity Company Standards

TES-P-119.19 Substation Building and Site Development
TES-P-119.21 Fire and Loss Prevention Requirements
32-TMSS-02-2014 SF6 Gas Insulated Switchgear and Hybrid SF6 Gas
Insulated Switchgear, 110 kV and above
43-TMSS-01 Shunt Capacitor Banks, 13.8 kV through 380 kV
58-TMSS-02 Specification for Air Core Series Reactor,
Substation Type, 13.8 kV through 380 kV
32-SDMS-09 Gas Insulated Metal Clad MV Switchgear 33 and
34.5 kV”

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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
Issue Date: 1 January 2018
Next Planned Update: 30 July 2020 Substations

4 Acronyms and Definitions

AIS: Air Insulated Switchgear manufactured to either 16-SAMSS-502 “Metal-

Enclosed Low-Voltage Switchgear Assemblies”, or 16-SAMSS-504 “Indoor Metal-
Clad Switchgear 1 to 38 kV”.

Approved Manufacturers: As listed within SAP.

Controlgear: Equipment manufactured to either 16-SAMSS-506 (Indoor Controlgear -

High Voltage), or 16-SAMSS-503 (Indoor Controlgear-Low Voltage).

GIB: Gas Insulated Bus

GIS: Indoor Gas Insulated Switchgear manufactured to either 32-TMSS-02 for 69 kV

and above, or 32-SDMS-09 for 33 kV and 34.5 kV.

Nominal Voltage: The nominal system voltages listed in SAES-P-100, Table 1.

Outdoor Substation: A substation, which consists of uninsulated open air busses or

outdoor equipment classified as primary distribution equipment irrespective of
secondary side switchgears, which could be indoor housed in air-conditioned building.

PSA: Power System Automation

SEC: Saudi Electricity Company

Secondary-Selective: A switchgear assembly consisting of two buses connected

with a single bus tie breaker. Each bus has one breaker to receive incoming power.
(i.e., power flow into and between the two busses is controlled with three breakers).
Also, referred to as “double-ended” switchgear.

Switchgear: Equipment manufactured to either 16-SAMSS-502 “Metal-Enclosed

Low-Voltage Switchgear Assemblies”, 16-SAMSS-504 “Indoor Metal-Clad Switchgear
1 to 38 kV”, 32-TMSS-02 “SF6 Gas Insulated Switchgear and Hybrid SF6 Gas Insulated
Switchgear, 110 kV and above”, or 32-SDMS-09 “Gas Insulated Metal Clad MV
Switchgear 33 and 34.5 kV”.

Utilization Equipment: Equipment whose primary function is to convert electrical

energy to another form, or store electrical energy. Examples of utilization equipment
would be motors, heaters, lamps, batteries, etc.). Equipment directly
feeding/controlling the utilization equipment is considered part of the utilization
equipment (for example, AFDs, reduced voltage starters, battery chargers etc.).

5 General

5.1 Terms in bold font are defined within Section 4.

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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
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Next Planned Update: 30 July 2020 Substations

5.2 Saudi Aramco defines a substation as any assemblage of electrical equipment

which includes a power transformer rated 751 kVA and larger or switchgear
rated 1 kV and higher.
Exception to 5.2:

This standard does not apply to manually operated pad-mounted switchgear

manufactured to 16-SAMSS-510 or pad-mounted distribution transformers
manufactured to 14-SAMSS-536.

5.3 Substations shall be in accordance with the ANSI/NFPA 70 (National Electric

Code) and ANSI C2 (National Electrical Safety Code) as supplemented by this
Standard.

5.4 Location of substation and substation equipment shall comply with SAES-B-055.
Substations shall be located in non-classified areas as defined by SAES-B-068.

5.5 Annunciator/monitor(s) shall be located within 10 meters from the main

entrance of the Substation; otherwise, a sign shall be posted at the entrance door
to show Annunciator/monitor(s) located on a building map. Each substation
building shall be provided with Annunciator/monitor(s) as per SAES-P-126
indicating the below status conditions.

5.5.1 A common trouble alarm shall be extended to a manned facility.

5.5.2 Monitors displaying information resident in local workstations.

5.5.3 The following status conditions shall be displayed, but not limited to:
a) Loss of circuit breaker tripping supply (Minimum one alarm per bus)
b) Loss of switchgear protection supply (Minimum one alarm per bus)
c) Loss of circuit breaker SF6 gas pressure
d) Low circuit breaker operating air pressure
e) Power transformer combustible gas present
f) Power transformer pressure relief valve operated
g) Power transformer Buchholz relay alarm
h) Power transformer Buchholz relay trip
i) On load tap changer oil flow relay trip
j) Power transformer high winding temperature
k) Power transformer loss of reference potential on Automatic Voltage
Regulator (AVR)
l) Power transformer loss of cooling fan supply voltage
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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
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Next Planned Update: 30 July 2020 Substations

m) Power transformer low transformer oil

n) Power transformer high oil temperature
o) Power transformer low tap changer oil level
p) Power transformer loss of tap changer motor operating supply
q) Power transformer tap changer failure
r) Online oil moisture/DGA alarm (if installed)
s) On load tap changer out of step.
Commentary Note:

Alarms are equipment specific. Some substations will not have all of
these alarms, or may require more as deemed necessary.

5.6 Tap changer, automatic voltage regulator, protection and circuit breaker control
panels shall be located inside the substation building when associated equipment
is located in an outdoor transformer yard or switchyard (for example,
transformer with an automatic tap changer or outdoor circuit breaker).
Exception to 5.6:

Built-in control panels within the SF6 dead tank circuit breakers shall be installed
with the breakers outside.

5.7 HV Control and Protection panels shall be supplied by an approved HV Control

and Protection panel manufacturer in compliance with 16-SAMSS-514. Control
and protection panels shall be arranged as follows for each: line protection and
metering, bus bar protection, feeder protection and metering, circuit breaker bay
control, breaker failure protection, and automatic voltage regulation.
Commentary Note:

Integrated panels to provide Control and Protection functions are allowed.

The manufacturer shall demonstrate capabilities and provide prior real installation
with no reliability impact.

Redundant protection panels shall be arranged in different lineups. The panels

shall be of simplex type having front door access with relays surface mounted
on the door. Circuit breaker control and indication functions shall be arranged
on the circuit breaker control panels to represent the substation configuration
and be interconnected by a mimic line diagram indelibly represented on the
surface of the panel with a maximum of one substation bay per panel.

5.8 Substations shall have a grounding system meeting the requirements of

SAES-P-111.

5.9 Substation bus configurations shall be as per Section 8 of this standard.

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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
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6 Substation Buildings

6.1 Substation buildings shall be constructed in accordance with SAES-M-100 and

SAES-B-014.

6.2 Passageways shall have an unobstructed width of 1.12 meter and shall provide a
minimum 2.3 meter headroom.

6.3 Cable trays and cable buses shall be installed as follows:

6.3.1 Parallel and at right angles to the building walls.

Commentary Note:

The exterior cable buses should have the minimum bend angles as most
of bends angles should be accommodated inside the substation.

6.3.2 Cable buses shall not be routed through the space, shown as Space (y)
in Figure 1 and Figure 2, which is directly in front of the adjacent large
transformer containing more than 7,570 liter of insulated oil.

6.3.3 Minimum of 200 mm of vertical clearance shall be provided between

cable trays.

6.3.4 The elevation of the bottom of the lowest interior cable tray shall be a
minimum of 2.67 meter above the main substation floor.

6.4 Substation service-entrance and branch circuit feeders conductors other than
grounding conductors shall enter or exit through the building walls, and enter
the equipment from the top.
Exceptions to 6.4:

- GIS requires cable basement/cable entry room. AIS or controlgear, housed in the
same GIS building in the vicinity of 33 or 34.5 kV GIS, or in the adjacent building to
GIS housing auxiliary controlgear(s) and/or switchgear(s), are allowed for bottom
entry/exit.

- Cable bus connections to transformer cable box bottom.

6.5 Maximum substation building length and width shall be limited to 75 and 15
meters respectively.
Exception to 6.5:

Substation housing 69 kV and above GIS are allowed to exceed 75 meters.

6.6 Structural design calculations to verify the buildings blast design capacity shall
be conducted in accordance with SAES-B-014.

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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
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Commentary Note:

SAES-B-014 has specific requirements for buildings in near or associated with

plants and may require a Building Risk Assessment Study that may affect the
construction of the building.

6.7 Substation interior and exterior lighting shall be provided as per SAES-P-123.

6.8 All interior substation lighting shall be fed from different buses of Secondary-
Selective low voltage switchgear.
Commentary Note:

This requirement can be implemented by equally distributing the substation lights

between two low voltage panelboards or feeding all substation lights from one
panelboard fed from two different power supplies through manual Transfer Switch
(TS).

6.9 Emergency interior illumination shall be provided in accordance of SAES-P-123,

section 5.6.6 and SAES-M-100 and shall be powered by one of the following:

6.10.1 Self-contained, battery-powered emergency lighting units, with integral

charger, which are automatically energized upon loss of the AC power.

6.10.2 Uninterruptible Power Supply (UPS) system located in the substation.

6.10 Emergency illuminated exit signs shall be provided in substations in accordance

with SAES-P-123, Section 5.6.5 and SAES-M-100.

6.11 DuplexVAC convenience outlets shall be provided throughout the substation

building. A minimum of one outlet shall be provided for each 6 meters of wall
space at 1 meter above the floor. A minimum of two outlets per substation shall
be provided.

6.12 Each substation building shall be provided with a redundant air-conditioning

system in accordance with SAES-K-001 and SAES-K-002. The indoor
temperature in battery rooms shall meet the requirements of SAES-K-002.
For normally occupied substations, the office facility or other occupied area
shall meet the indoor temperature requirements of SAES-K-001 for offices.
Temperature requirements for unattended substations are also specified in
SAES-K-001.
Commentary Note:

Unattended substations require a design maximum temperature of 35°C;

however, the HVAC for the battery room is required to maintain 25°C.

6.13 Substation roof drainage shall not be to the transformer yard side of the
substation building.

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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
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6.14 If a substation is to be constructed over existing pipelines, the substation floor

shall be elevated a minimum of 1.8 m above grade. The space below the
elevated substations shall have the following characteristics:

6.14.1 Be freely ventilated on at least three sides.

6.14.2 The ground below the building shall be at or above finished grade.

6.14.3 Be enclosed with grillwork suitable for the environmental conditions

and a lockable gate to permit access only to authorized personnel.
The grillwork and the gate shall be connected to the substation
grounding system.

6.14.4 Shall not drain to the transformer yard side of the substation building.

6.14.5 The side of the building adjacent to the transformer yard shall have a
solid wall (fire-rating the same as the building wall) that separates the
space from the transformer yard.
Commentary Note:

Note that paragraph 6.4 does not allow cable or electrical raceways to
enter/exit through the floor, except GIS installations as per exception to
6.4.

6.15 The concrete floor in front of switchgear shall be flush with the roller level of
lower breaker carriage rack and have a smooth surface to facilitate removal and
rolling of breaker. This floor area shall be surface hardened for rolling stock.

6.16 Underneath switchgear and controlgear, one of the following shall be provided
to ensure the equipment is maintained on an even plane:

6.16.1 Leveling steel beams or channels. Design and installation of these

channels shall be in accordance with the recommendations of the
switchgear and controlgear manufacturer.

6.16.2 The floor shall be horizontal in both planes with a maximum surface
height variation less than 5 mm per 3 meters.

6.17 Substation buildings shall have a minimum 2 hour fire rating and be constructed
in accordance with SAES-M-100, and where required by SAES-O-Series as
vital equipment.

6.18 A battery room and battery handling facilities shall be provided for stationary
batteries in accordance with SAES-P-103.

6.19 Circuit breaker testing facilities and operating tools shall be provided and

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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
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installed in the substation in accordance with SAES-P-116.

6.20 Substation buildings with single-ended switchgear shall be designed to

accommodate future double-ending.
Commentary Note:

Since providing for future double-ending will require additional floor space,
this should be addressed in the design basis or project proposal documents.

6.21 Substation buildings shall have a telephone and data communications. This shall
include connection to the plant local area network. SAES-P-126 mandates a
dedicated (stand lone) Ethernet network for the power system automation.

6.22 Substation buildings shall have provisions for mounting and protecting as-built
key one-line diagrams for ready reference of operating personnel.

6.23 Substation buildings shall have smoke detection systems per SAES-B-014.

6.24 Substation buildings shall have Distributed Control System (DCS) Input/Output
(I/O) ports available. This shall be implemented either by remote I/O racks(s)
and/or DCS controllers within the substation. Design, installation, and
interconnection to plant DCS system shall be per the applicable SAES-J-Series.

6.25 Substation buildings housing 69 kV and above GIS and its adjacent building
housing auxiliary controlgear(s) and/or switchgear(s) should be constructed with
same elevation level as main building to avoid re-entrance corners or recessed
areas as per SAES-M-009.

6.26 The GIS building shall be constructed with an underground cable basement/cable
entry room as specified in TES-P-119.19 and TES-P-119.21. The building
basement floor shall be at least 1.0 meter above the ground water table level.
Exception to 6.26:

In areas with high underground water level, an elevated GIS building, without
basement/cable entry room, is allowed.

6.27 Substation buildings shall be provided with exit doors every 15 meters in the
long side wall, which is opposite to transformers side.

6.28 Substation buildings shall be provided with a reflective building identification

sign at the upwind side to facilitate identification of substation building during
emergencies, consult with Fire Prevention Department for specifics.

6.29 Substation buildings housing 33 kV or 34.5 kV GIS shall be equipped with

integrated arc duct to direct gas/vapor away from operators and prevent solid
parties from uncontrolled spreading. The pressure surge shall be cooled in the
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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
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absorber before its release outside the substation building. The duct shall be
oriented in horizontal plane, and the exhaust shall be extended at least 2 meters
beyond the periphery of the switchgear. The duct outlet shall exhaust into a
restricted access area that shall extend a minimum of 3 meters directly in front
of the exhaust outlet and 1.5 meters to each side of the exhaust outlet.

7 Substation Yard

7.1 For on-shore, outdoor installations, pad-mounted electrical equipment shall be

placed on a level concrete pad, the top of which is elevated a minimum of
100 mm above natural grade. The following minimum clearances shall apply:

7.1.1 A minimum working clearance of 2 meters on all sides.

Exception to 7.1.1:

Clearance between pad-mounted electrical equipment and fences or

walls installed for the purpose of protecting the equipment from
unauthorized access is permitted to be reduced to a minimum of 1 meter
with the concurrence of the proponent, provided that the 3-meter
clearance is maintained for equipment doors and access panels required
to be opened for normal maintenance and/or operations.

7.1.2 A minimum working clearance of 3 meters on the sides of the

equipment having doors or access panels which can be opened to
expose live parts.

7.1.3 The intent of the above requirements is met by gate(s) which can be
opened to provide the required clearance.

7.2 Transformer clearances and fire barriers shall be as follows:

7.2.1 For transformers containing 7,570 liters and less of insulated oil:
Clearance shall be per 7.1 above.

7.2.2 For transformers containing more than 7,570 liter of insulated oil:
a) Separation from buildings:
If the building has a fire rating; 6.1 meters or greater (Figure 1).
b) Separation from any other substation yard equipment, for
example, transformers, reactors, capacitor banks:
If no fire barrier or barrier fire rating is less than 1 hour: greater
than a minimum of 9.1 meters of clear space (Figure 2).

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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
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7.2.3 Fire barrier characteristics shall be as follows:

a) The height of a fire barrier shall not be less than 300 mm above
the height of transformer tank, conservator (if applicable),
transformer bushing, and pressure relief vents, etc. (Figure 1).

b) The fire barrier shall extend at least 600 mm horizontal beyond

the line of sight between all points on adjacent transformers
(Figure 1). The height of the fire barrier shall be enough to break
the line-of-sight from any point on the top of the transformer and
adjacent transformer.

PLAN (TOP) SECTION (SIDE)

VIEW VIEW
None Fire Rated Substation

X
2 hours Firewall
Building

Building
Substation

2 hours Firewall
X

<X <X

Generic

PLAN (TOP) SECTION (SIDE)

VIEW VIEW
6.1m
Figure 1
2 hours Fire rated Substation Building

Space (y)

2m
600 mm
1 hour Firewall
Building 2 hours
Substation
Firewall

300 mm
600 mm

2m

Space (y) 600 mm (dike height)

600 mm

6.1m

6.1m

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6.1m

2 hours Fire rated Substation Building

Space (y)

9.1 m

Space (y)

6.1m

Figure 2

7.3 Transformer oil containment/drainage shall be as follows:

7.3.1 For power transformers up to 2.5 MVA no drainage is required and oil
containment shall be in the form of toe walls of sufficient height and
area to contain twice the oil volume of the transformer.
Exception to 7.3.1:

For transformers containing 2,500 liters and less of insulated oil,

neither oil containment, drainage, nor toe walls are required.

7.3.2 For power transformers 2.5 MVA and above, the following oil
containment/drainage system shall be provided:
a) Oil containment and drainage systems shall meet the general
requirements of IEEE Std 980 and the specific requirements of
SAES-S-020.
b) Oil containment systems shall be designed to withstand a
minimum 3 hours fire occurring within the bounds of the
containment system.
c) Oil containment shall be in the form of a concrete pit constructed
around the transformer foundation to contain 110% of
transformer oil. The perimeter of the spill containment shall be
located beyond the portion of the electrical equipment containing
oil, based on the height of bushing and conservator. The pit shall
be equipped with a steel grating covered with crushed rock to a

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minimum thickness of 300 mm for fire quenching and have the

following characteristics:
i) The crushed rock shall be a minimum sieve size of 25 mm
uniformly graded.
ii) The steel grating mesh size shall be less than 25 mm².
iii) A removable section, with a steel lid not covered with
crushed rock, shall be provided in a corner of the steel
grating to allow access for cleaning.
iv) A sump shall be provided at a corner of the pit for
collection of rain water or oil. The sump shall have means
of drainage either by suitable connection to sewers or other
means of fluid removal.
Commentary Note:

Oil containment shall be designed to accommodate environmental

conditions. Pits completely filled with crushed rock shall not be used
since they must be made extremely large to contain the oil volume plus
the crushed rock and they cannot be easily cleaned of wind-blown sand
accumulation.

7.4 Transformer Neutral Ground Resister (NGR) shall be located in the substation
yard. NGR shall be constructed as per 14-SAMSS-531 and shall not be
mounted on a transformer.

7.5 Fire water system design shall be in compliance with SAES-B-017 and
SAES-B-019 for transformer, substation, and substation yard protection.

7.6 The substation yard shall be completely paved as a plant area in accordance with
the requirements of SAES-Q-006. The thickness of the combined asphalt layers
shall not be less than 10 cm.
Commentary Note:

The high surface resistivity of an asphalt-aggregate mixture under both wet and
dry conditions reduces the number of ground grid conductors required to obtain
safe step and touch potentials during ground faults.

7.7 Substation yards shall be enclosed. Fences shall be constructed in accordance

with the requirements of SAES-M-006. Warning signs shall be in accordance
with Saudi Aramco Standard Drawing AB-036319 and shall be posted on the
fence at intervals not to exceed 6 meters.

7.8 Equipment located in the substation yard shall not be accessible from the roof of
the substation building.
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7.9 Utility receptacles shall be provided with the following characteristics:

7.9.1 Sufficient receptacles shall be installed inside and outside the

substation building so that a receptacle is located within 6 meter of
each power circuit breaker (indoor and outdoor) and each power
transformer.

7.9.2 Outdoor units shall be equipped with self-closing covers which are
weatherproof when the covers are closed.

7.9.3 Outdoor receptacles shall be fed from a Ground Fault Circuit Breaker
with 5 mA trip or from Equipment Protection Device (EPDs) with
nominal 30 mA trip. Receptacles with integral ground fault protection
are not acceptable).

7.9.4 Receptacles shall meet SASO 2203/2003 requirement.

7.10 The Outdoor Substation switchyard (69 kV and above) shall be in accordance
with the following:
Commentary Note:

The Outdoor Substation construction is prohibited for new installations and only
allowed for expanding existing substations.

7.10.1 Bus Design

a) Outdoor Rigid Bus design shall be in accordance with
IEEE Std 605 for Design of Substation Rigid-Bus Structures.
b) Bus conductors shall be manufactured from Schedule 40/80
seamless aluminum alloy tubing, temper 6063-T6.
c) Vertical bus deflection under maximum loading conditions,
including the weight of vibration damping measures, shall be
limited to 0.5% of span length.
d) Maximum horizontal span length between bus supports shall be
10 meters.
e) Vibration damping shall be accomplished by inserting stranded
bare conductor inside the rigid bus tubing. The stranded conductor
shall be of the same material as the tubing to prevent corrosion.
f) The rigid bus shall be joined by welding. Bolted joints in the
tubular bus are not acceptable.
g) Connections to the tubular bus shall either be welded or via
welded pads providing standard NEMA bolt pattern.
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Issue Date: 1 January 2018
Next Planned Update: 30 July 2020 Substations

h) Flexible joints shall be provided to control expansion on bus runs

longer than 30 meters.
i) Welded grounding lugs shall be provided on the bus tubing for
the attachment of safety grounds. The ground lugs shall be
located on the rigid bus on both sides of disconnect switches and
circuit breakers.
j) Connection from rigid bus to circuit breakers shall be via
stranded cable jumpers with compression fittings and NEMA bolt
pattern for both the bus and circuit breaker connections.
k) Rigid bus supports shall be constructed from steel I-beam, steel
pipe or square section steel tubing.
l) Composite bus support post type insulators shall be used
comprising silicone rubber compound external insulation over a
solid fiberglass core with ANSI/IEEE/NEMA bolt patterns.

7.10.2 Electrical clearances shall be in accordance with ANSI C2 (NESC).

7.10.3 Lightning shielding shall be per SAES-P-111.

7.10.4 The outdoor HV substation and switchyard dimensions shall be as

indicated in Table 1 and Figure 3.

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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
Issue Date: 1 January 2018
Next Planned Update: 30 July 2020 Substations

Table 1 - Outdoor HV Substation and Switchyard Dimensions (in meters)

Voltage A B C D E F G H

69 kV 4.3 4.0 2.8 1.6 4.9 1.3 15.3 4.6

115 kV 7.4 4.0 3.1 4.9 4.9 2.5 15.3 4.6
230 kV 9.1 6.2 5.0 4.9 6 3.1 19 4.6

Figure 3 – Outdoor Substation Dimension

7.11 Exposed equipment insulators, except for surge arresters, shall have a minimum
leakage distance of 40 mm per kV line-to-line of the nominal system voltage.

7.12 Surge arresters shall be installed on systems with nominal operating voltages of
13.8 kV and above at the following locations:

7.12.1 At interface points between overhead lines, open bus, and underground
lines. This include open bus transition used to connect underground
cables to air type transformer bushings.

7.12.2 On power transformer terminals which are connected to overhead

lines, open bus, cable circuits originating from GIS, or GIB.

7.12.3 On dry-type power transformers terminals which are connected to

cables originating from vacuum circuit breakers, where cable length
less than 30 meters, RC Snubber surge protection.

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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
Issue Date: 1 January 2018
Next Planned Update: 30 July 2020 Substations

7.13 Surge arresters shall have the following characteristics:

7.13.1 Surge arrester shall be equipped with operation counters.

7.13.2 Surge arrester shall be of the composite insulation type with silicone
rubber compound external insulation over a hermetically sealed
fiberglass core.

7.13.3 Surge arrester grounding terminals shall be connected, with minimum

bends, directly to the ground bus or grid or, in the case of surge
arresters mounted on transformers, directly to the grounding pad
provided on the transformer.

7.13.4 The voltage rating of arresters used in substations shall be as indicated

in Table 2.

Table 2 - Required Arrester Ratings

Nominal Maximum Maximum
Duty Cycle
System System Continuous Specific
Rating
Voltage Voltage Rating Operating Voltage Note(s)
(kV rms)
(kV) (kV) (kV rms)
13.8 15 12 10 and 12.7 S1
34.5 38 30 24.4
69 76 60 48.0
110 121 96 76
115 127 108 84
132 145 120 92
230 253 192 152
380 418 360 265
Specific Note(s):
S1 The Maximum Continuous Operating Voltage is 10 and 12.7 for solidly-grounded and resistance /
un-grounded respectively.

8 Substation Bus Configurations

8.1 All switchgears operating at 33 kV or above shall be of indoor GIS type.

8.2 The bus configuration of 33 or 34.5 kV GIS shall be single-bus with normally
open bus-section circuit breaker.

8.3 The mandatory requirements for selecting and configuring GIS bus designs for
substations operating at 69 kV or above are defined in Table 3.
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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
Issue Date: 1 January 2018
Next Planned Update: 30 July 2020 Substations

Commentary Note:

The designer shall base configuration selection on Life-Cycle Cost Analysis

covering several factors based on requirements, criticality, redundancy, number of
incoming and outgoing circuits, economics, maintenance, and operation cost.

Table 3 - GIS Bus Configurations of 69 kV and Above

Nominal Power Generation
Utility Supply Only
System and Utility Supply Specific
Voltage Note(s)
(kV) Bus Configuration

380 Breaker-and-a-Half S1

Breaker-and-a-Half S1
2-2-8 2-2-8 or 2-1-6
S2
Double-Bus-Single-Breaker Double-Bus-Single-Breaker
230
- Ring-Bus S3

- Radial-Bus S5
2-2-8 2-1-6
S2
Double-Bus-Single-Breaker Double-Bus-Single-Breaker
Ring-Bus Ring-Bus S3
69 to 132
- Inverted-PI S4

- Radial-Bus S5

Specific Note(s):
S1 Breaker-and-a-Half Configuration:
 Spare bay breakers shall not be installed.
 Layout shall accommodate future addition of necessary breakers to complete bay
configuration.
S2 Double-Bus-Single-Breaker Configuration:
 (2-2-8) arrangement consists of two (2) sectionalizers, two (2) couplers,
and eight (8) disconnectors, or
 (2-1-6) arrangement consists of two (2) sectionalizers, one (1) coupler,
and six (6) disconnectors configured in Z shape.
 Bus sectionalizer and bus coupler shall be operated normally closed.
 Redundant feeders or redundant power sources shall not be connected to the same
bus segment or connected to the bus segments connected by the bus coupler.
S3 Ring-Bus Configuration:
 Redundant generation sources and redundant utility sources shall not be connected
to adjacent positions.
 All breakers shall be operated normally closed.
 The number of positions for onshore and offshore applications shall be limited to
four (4), and six (6), respectively.
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Document Responsibility: Electrical Substations Equipment Standards Committee SAES-P-119
Issue Date: 1 January 2018
Next Planned Update: 30 July 2020 Substations

S4 Inverted-PI Configuration:
 Limited to two (2) primary and two (2) secondary feeders.
 No breakers shall be installed in the secondary feeders.
 The bus coupler shall be operated normally closed.
S5 Radial-Bus Configuration:
 Acceptable for substations dedicated to feed gas or oil production wellsites.
 The configuration shall include spare incoming breaker for future alternate supply.

Revision Summary
5 November 2012 Major revision.
27 April 2014 Editorial revision to synchronize substation receptacle requirement with SAES-P-100
requirement.
17 February 2015 Minor revision by adding 600 mm dike between transformer fire wall and substation building
and detailing the grading and oil containment pits for power transformers.
30 July 2017 Major revision by revising substations bus configurations and mandate GIS modular design
for 33 kV and above, increase substation length, and other improvements.
1 January 2018 Editorial revision to modify paragraphs 6.6.

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