DP class notation

IMO
equipment BV DNV ABS GL LR NK RINA RS IRS CCS NMD
class
Norwegian
American Bureau of Indian Register of China Classification
Bureau Veritas Det Norske Veritas Germanischer Lloyd Lloyds Register of Shipping Nippon Kaiji Kyokai Registro Italiano Navale Russian Register of Shipping Maritime
Shipping Shipping Society
Directorate
DYNAPOS DYNAPOS
DPS 0 DPS-0 DP (CM) DYNAPOS SAM GS(KK) DPS 0
SAM AUTS
DYNAPOS
Class 1 DYNAPOS AUT DPS 1 DPS-1 DP 1 DP (AM) Class A DP DYNAPOS AM/AT DYNPOS-1 GS(SK) DP-1 DPS 1
AM/AT
DYNAPOS DYNAPOS
Class 2 DPS 2 DPS-2 DP 2 DP (AA) Class B DP DYNAPOS AM/AT R DYNPOS-2 GS(SS) DP-2 DPS 2
AM/AT R AUTR
DYNAPOS DYNAPOS
Class 3 DPS 3 DPS-3 DP 3 DP (AAA) Class C DP DYNAPOS AM/AT RS DYNPOS-3 DP-3 DPS 3
AM/AT RS AUTRO

Source: Capt. D. Bray FNI – DP Operator’s Handbook. The Nautical Institute, 2010. P.1
IMO MSC/Circ.645, Guidelines for vessels with dynamic positioning systems
Classification societies
DP0 IMO BV DNV ABS GL LR NK RINA RUSSIAN INDIA CCS

Generator and prime movers - Non-Redundant Non-Redundant Non-Redundant - Non-Redundant - - - Non-Redundant -

Main switchboard - Non-Redundant 1 1 - 1 - - - Non-Redundant -
Bus tie breaker - No 0 0 - 0 - - - No -
Distribution system - Non-Redundant Non-Redundant Non-Redundant - Non-Redundant - - - Non-Redundant -
Power management - Non-Redundant No No - Yes - - - No -
Arrangement of thruster - Non-Redundant Non-Redundant Non-Redundant - Non-Redundant - - - Non-Redundant -
Auto control; No computer systems - 1 1 1 - 1 - - - 1 -
Manual control: joystick with auto heading - May be fitted No No - No - - - 1 (No) -
Single levers for each thruster - Yes Yes Yes - Yes - - - - -
Pos ref systems - 1 1 1 - 1 - - - 1 -
Wind - 1 1 1 - 1 - - - 1 -
VRS - 1 1 1 - 1 - - - 1 -
Gyro compass - 1 1 1 - 1 - - - 1 -
UPS - 1 0 0 - 0 - - - - -
Alternative control station for backup unit - N/A No N/A - No - - - N/A -

DP0 IMO BV DNV ABS GL LR NK RINA RUSSIAN INDIA CCS

Consequence Analysis - NO NO NO - NO - - NO -
FMEA - NO NO YES - NO - - NO -
Installation manual/systems drawings - YES YES YES - YES - - YES -
FAT/CAT - YES YES YES - YES - - YES -
Approval of cable routing for power and control
circuits - NO NO NO - NO - - YES -
No single fault can result in more than 50% loss
of DP capacity - N/A NO NO - NO - - NO -
Equivalent to IMO Class - N/A N/A N/A - N/A - N/A -
DP1 IMO BV DNV ABS GL LR NK RINA RUSSIAN INDIA CCS

Generator and prime movers Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant
Main switchboard 1 1 1 1 1 1 1 1 1 Non-Redundant 1
Bus tie breaker 0 0 0 0 0 0 0 0 0 No 0
Distribution system Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant
Power management No Non-Redundant No No No Yes - Non-Redundant - No No
Arrangement of thruster Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant Non-Redundant
Auto control; No computer systems 1 Non-Redundant 1 1 1 1 1 Non-Redundant 1 1 1
Manual control: joystick with auto heading Yes Yes Yes Yes Yes Yes Yes Yes Yes 1 (yes) Yes
Single levers for each thruster Yes Yes Yes Yes Yes Yes - Yes Yes - Yes
Pos ref systems 1 2 2 2 1 2 1 2 1/2 2 2
Wind 1 2 1 2 1 2 1 2 1 2 1
VRS 1 2 1 1 1 2 1 2 1 2 1
Gyro compass 1 2 1 2 1 2 1 2 1 2 1
UPS 1 1 1 1 1 1 1 1 1 - 1
Alternative control station for backup unit No N/A No N/A N/A No N/A N/A No N/A No

DP1 IMO BV DNV ABS GL LR NK RINA RUSSIAN INDIA CCS

Consequence Analysis NO NO NO NO NO NO NO NO NO NO NO
FMEA NO NO NO YES NO NO NO NO - NO YES
Installation manual/systems drawings YES YES YES YES YES YES YES YES YES YES YES
FAT/CAT YES YES YES YES YES YES YES YES - YES YES
Approval of cable routing for power and control
circuits NO NO NO NO NO NO - NO NO YES NO
No single fault can result in more than 50% loss
of DP capacity NO N/A NO NO N/A NO - N/A - NO N/A
Equivalent to IMO Class 1 1 1 1 1 1 1 1 1 1 1
DP2 IMO BV DNV ABS GL LR NK RINA RUSSIAN INDIA CCS

Generator and prime movers Redundant Redundant Redundant Redundant Redundant Redundant Redundant Redundant Redundant Redundant Redundant
Main switchboard 1 with bus tie Redundant 1 with bus tie 1 with bus tie 1 1 with bus tie 1 Redundant 1 with bus tie Redundant 1
Bus tie breaker 1 Yes 1 1 1 1 1 Yes 1 Yes Yes
Redundant with Redundant with
Distribution system Redundant separation Redundant Redundant Redundant Redundant Redundant RWS Redundant Redundant separation
No strict requirement to be If installed, adequate
Power management redundant Redundant Yes Yes redundancy Yes - Redundant - No Installed
Arrangement of thruster Redundant Redundant Redundant Redundant Redundant Redundant Redundant Redundant Redundant Redundant Redundant
Auto control; No computer systems 2 2 2 2 2 2 2 2 2 2 2
Manual control: joystick with auto heading Yes Yes Yes Yes Yes Yes Yes Yes Yes No Yes
Single levers for each thruster Yes Yes Yes Yes Yes Yes - Yes Yes - Yes
Pos ref systems 3 3 3 3 3 3 3 3 3 3 3
Wind 2 2 2 2 2 2 2 2 3 2 2
VRS 2/3 2 2 2/3 2 2/3 2 2 3 2 2 or 3
Gyro compass 3 3 3 2 2 or 3 3 2 or 3 3 3 2 2
UPS 2 2 2 1 2 2 2 2 2 - 1
Alternative control station for backup unit No N/A No N/A N/A No N/A N/A No N/A No

DP2 IMO BV DNV ABS GL LR NK RINA RUSSIAN INDIA CCS

Consequence Analysis YES YES YES YES YES NO YES YES YES YES YES
FMEA NO YES YES YES YES YES YES YES - YES YES
Installation manual/systems drawings YES YES YES YES YES YES YES YES YES YES YES
FAT/CAT YES YES YES YES YES YES YES YES - YES YES
Approval of cable routing for power and control
circuits YES NO YES YES NO YES - NO YES YES NO
No single fault can result in more than 50% loss
of DP capacity YES YES YES YES YES YES - YES - YES YES
Equivalent to IMO Class 2 2 2 2 2 2 2 2 2 2 2
DP3 IMO BV DNV ABS GL LR NK RINA RUSSIAN INDIA CCS

Generator and prime movers Redundant, in separate compartments Redundant with separations Redundant, in separate compartments Redundant, in separate compartments Redundant, separate compartments Redundant, in separate compartments Redundant, separate compartments - Redundant, in separate compartments - Redundant in separate compartments
2 with normally open bus ties in separate 2 with normally open bus ties in separate 2 with normally open bus ties in separate 2 with normally open bus ties in separate compartments,
Main switchboard compartments, A60 Redundant with separations 2 in separate compartments compartments 2 with normally open bus-ties in separate compartments compartments 2 with normally open bus ties in separate compartments - A60 - 2, in separate compartments
Bus tie breaker 2 Yes 2, 1 breaker in each MSB 2 2 2 2 - 2 - Yes
Distribution system Redundat, through separate compartments Redundant Redundant, through separate compartments Redundant, throguh separate compartments Redundant through separate compartments Redundant, through separate compartments Redundant through separate compartments - Redundant, through separate compartments - Redundant in separate compartments
Power management Note 1 Redundant with separations Yes Yes If installed, adequate redundancy Yes - - Installed

Separate compartments, retain at least 50% thrust in

case loss of one compartment. Thrust max. Load
Arrangement of thruster Separate compartments redundant Redundant with separations Redundant-in separate compartments Redundant in separate compartments Redundant diagram under DP operation is required Redundant - Separate compartments redundant - Redundant, separate compartmetns
Auto control; No computer systems 2 + 1 back-up 2 + 1 B/U system 2 + 1 in alternate control station 2 + 1 in alternate control station 2 + 1 in separate compartments 2 + 1 in alternate control station 2 + 1 in separate compartments - 2 + 1 back-up - 2 + 1 B/U system
Manual control: joystick with auto heading Yes Yes Yes Yes Yes Yes Yes - Yes - Yes
Single levers for each thruster Yes Yes Yes Yes Yes Yes - Yes - Yes
3 whereof 1 in alternate control station directly 3 whereof 1 in alternate control station directly connected 3 whereof 1 in altenate control station w/a repeater in 3 whereof 1 in alternate control stationdirectly connected to 3 whereof 1 in alternate control station directly
Pos ref systems connected to Back-up system to back up system 3 whereof 1 in alternate control 3 whereof 1 in alternate control station 3 whereof 1 connected to back-up control system main control unit 3 whereof 1 connected to back-up control system - back-up system - connected to back-up system
Whereof 1 in alternate control Whereof 1 in alternate control One of each connected to back-up control
Wind 3 station 2 Whereof 1 in alternate control station 2 Whereof 1 in alternate control station 2 station 2 One of each connected to back-up control system 2 Whereof 1 in alternate control station 2 system - 3 Plus one more in alternate control station - 2 Whereof 1 in alternate control station
VRS 3 As above 2 As above 2 As above 3 As above 2 As above 3 As above 2 As above - 3 As above - 2 As above
Gyro compass 3 As above 3 As above 3 As above 3 As above 3 As above 3 As above 3 As above - 3 As above - 2 As above
UPS 2 + 1 separate compartment 3 whereof one in separate compartment 3 whereof 1 in separate compartment 1 + 1 separate compartment 2 + 1 in separate compartments 2 + 1 separate compartment 2 + 1 in separate compartments - 2 + 1 separate compartment - 2 whereof one in separate compartment
Alternative control station for backup unit Yes Yes Yes Yes Yes Yes Yes - Yes - Yes

DP3 BV DNV ABS GL LR NK RINA RUSSIAN INDIA CCS

Consequence Analysis YES YES YES YES YES NO YES - YES - YES
FMEA NO YES YES YES YES YES YES - - - YES
Installation manual/systems drawings YES YES YES YES YES YES YES - YES - YES
FAT/CAT YES YES YES YES YES YES YES - - - YES
Approval of cable routing for power and control
circuits YES NO YES YES NO YES - - YES - NO

No single fault can result in more than 50% loss

of DP capacity YES YES YES *includes also fire and flooding YES *includes also fire and flooding YES YES - - - YES
Equivalent to IMO Class 3 3 3 3 3 3 3 3 - 3