new class notation abstract_spec-2002_v2

Kongsberg Maritime AS

Class Notation Abstract

and Comparison

for DP Systems

Project: -

Product Dynamic Positioning

Synopsis: This document includes a comparison of DP-rules for IMO, ABS, DNV, LR, BV, RINA, GL, ClassNK, CCS, RMR and IRS.

Document number: SPEC-2002 Revision: 2

Customer doc number: Document version:

Contract number: Number of pages: 76

Rev. Date Reason for issue Made by Checked Approved

E (5) 12.05.2004 Updated H Røkeberg S Solbakken L Kr Moen

1 14.03.2005 Transferred to KM Quality Management System

- - VF

2 16.04.2007 Updated H. Røkeberg S.Solbakken V. Faaberg


Class Notation Abstract_SPEC-2002_v2 of 76

History in Handbooks & Procedures

Revision Date Description of Change

E(5) 12-May-04 Updated. Editorial changes due to new company name and template and updated paragraphs according to the classification rules.

1 14-March-05 Transferred to KM Quality Management System

2 16-April-07 Updated/extended. Included CCS, RMR and IRS. Thusters and Position reference systems have been given particular attention.

References

Doc No Description



Definitions / Abbreviations

ABS American Bureau of Shipping

BV Bureau Veritas

CCS China Classification Society

ClassNK Nippon Kaiji Kyokai

DNV Det Norske Veritas

FSVAD Flag State Verification and Acceptance Document

GL Germanischer Lloyd

IMO International Maritime Organization

IRS Indian Register of Shipping

LR Lloyd's Register of Shipping

NK Nippon Kaiji Kyokai

NMD Norwegian Maritime Directorate

RINA Registro Italiano Naval

RMR Russian Maritime Register of Shipping

USCG U. S. Coast Guard



Table of contents

1 INTRODUCTION....................................................................................................5 1.1 Purpose ..................................................................................................................5 1.2 Quotes....................................................................................................................5 1.3 Type Approval.......................................................................................................5 1.4 EC Type-Examination Certificates........................................................................6 1.5 QS – Certificate of Assessment - EC ....................................................................6

2 IMO DEFINITIONS (REF. MSC/CIRC. 645. 6 JUNE 1994) .............................7 2.1 DEFINITIONS ......................................................................................................7 2.2 Other definitions ....................................................................................................8

3 DP-OPERATIONS ................................................................................................10

4 CLASSIFICATION PRINCIPLES AND PRACTICE ......................................14

5 COMMENTS TO THE DP RULE COMPARISON TO IMO GUIDELINES17

6 RULES FOR INSTRUMENTATION AND AUTOMATION ..........................21 6.1 LIST OF CLASS RULES FOR AUTOMATION SYSTEMS............................21

7 IMO CERTIFICATION .......................................................................................25

8 ABS CERTIFICATION ........................................................................................31

9 DNV CERTIFICATION .......................................................................................36

10 LR-CERTIFICATION......................................................................................42

11 BUREAU VERITAS CERTIFICATION........................................................48

12 REGISTRO ITALIANO NAVALE CERTIFICATION ...............................53

13 GERMANISCHER LLOYD ............................................................................54

14 NIPPON KAIJI KYOKAI (CLASSNK) .........................................................59

15 CCS CERTIFICATION ...................................................................................64

16 RMR, RUSSIAN MARITIME REGISTER OF SHIPPING.........................68

17 IRS, INDIAN REGISTER OF SHIPPING .....................................................73



1 INTRODUCTION

1.1 Purpose This document is an abstract and a comparison table between different Classification Societies for DP Rules in addition to IMO.

The Quality Management unit of Kongsberg Maritime AS produces this document and will not be responsible for any misinterpretation of the rules stated.

For additional information and comments, please read the Class Notation document from each Classification Society.

1.2 Quotes When Rules and Guidelines quotes are used, these are printed in Italics to ease identification.

1.3 Type Approval DNV:

At the time of writing, the current K-Pos-line and SDP-line are type approved with DNV, including hardware, software basis and software for specific applications, but excluding sensors, position reference, and UPS.

DNV A-10270 Dynamic Positioning Control System, Position Mooring System and Independent Joystick Control System Type designations: KONGSBERG cPos, K-Pos DP, K-Pos PM, K-Pos DPM, cJoy DP basis release 7.0, update 2 onwards DNV A-10269 (DNV A-9664's successor) Dynamic Positioning Control System, Position Mooring System and Independent Joystick Control System Type designations: KONGSBERG cPos, SDP, SPM, SDPM, cJoy, SJS SDP basis release 6.1, update 1 onwards SDP basis release 6.2, update 0 onwards (SJS, SDP OT; obsolete from SDP basis release 6.2)

ABS:

K-Pos Type Approval is ongoing per February 15th 2007.

LR:

K-Pos Type Approval process was initiated in February 2007.



1.4 EC Type-Examination Certificates At the time of writing the EC Type-Examination Certificates for “DP Autopilot” are:

MED-B-4133 (with DNV as the Notified body) Product: Heading control system (HCS) Type designation(s): K-Pos Heading Control System DP basis release 7.0, update 2 onwards USCG Approval information included. MED-B-4173 (MED-B-3025s successor with DNV as the Notified body) Product: Heading control system (HCS) Type designation: SDP Heading Control System SDP basis release 6.1, update 1 onwards SDP basis release 6.2, update 0 onwards (SDP OT; obsolete from SDP basis release 6.2) USCG Approval information included.

1.5 QS – Certificate of Assessment - EC At the time of writing the “QS – Certificate of Assessment – EC” is:

MED-D-874 (with DNV as the Notified body) Quality System for the products: A.1/4 Navigation equipment Appendix Rev. No.4 is expected to include:

• EC Type Examination Cert. No. MED-B-4133 and MED-B-4173 will be listed with its associated “USCG approval number”.

• USCG approval and marking information.



2 IMO DEFINITIONS (REF. MSC/CIRC. 645. 6 JUNE 1994)

2.1 DEFINITIONS In addition to the definition in the MODU Code 1989 the following definitions are necessary for the guidelines:

2.1.1 Dynamically positioned vessel (DP-Vessel) means a unit or a vessel which automatically maintains its position (fixed location or predetermined track) exclusively by means of thruster force.

2.1.2 Dynamic positioning system (DP-system) means the complete installation necessary for dynamically positioning a vessel comprising the following sub-systems:

.1 Power system

.2 Thruster system, and

.3 DP-control system

2.1.3 Position keeping means maintaining a desired position within the normal excursions of the control system and the environmental conditions.

2.1.4 Power system means all components and systems necessary to supply the DP-system with power. The power system includes:

.1 Prime movers with necessary auxiliary systems including piping,

.2 Generators.

.3 Switchboards, and

.4 Distributing system (cabling and cable routing)

2.1.5 Thruster system means all components and systems necessary to supply the DP-system with thrust force and direction. The thruster system includes:

.1 Thruster with drive units and necessary auxiliary systems including piping.

.2 Main propellers and rudders if these are under the control of the DP-system.

.3 Thruster control electronics,

.4 Manual thruster controls, and

.5 Associated cabling and cable routing

2.1.6 DP-control system means all control components and systems, hardware and software necessary to dynamically position the vessel. The DP-control system consists of the following:



.1 Computer system/joystick system.

.2 Sensor system,

.3 Display system (operator panels),

.4 Position reference system, and

.5 Associated cabling and cable routing.

2.1.7 Computer system means a system consisting of one or several computers including software and their interfaces.

2.1.8 Redundancy means ability of a component or system to maintain or restore its function, when a single failure has occurred. Redundancy can be achieved for instance by installation of multiple components, systems or alternative means of performing a function.

2.2 Other definitions

Flag State is the country in which the vessel is registered by the National Authority. The vessel shall carry the Flag State’s flag, and show the port of registry at the stern, but may have no other apparent connection to the Flag State.

Coastal State is the country where the vessel is located when it is not in international waters, i.e. when in harbour or in some country’s territorial water. The Coastal State may apply restrictions that exceed those of the Flag State.

Main Class is the set of rules that are compulsory for any vessel classified by the specific Classification Society. Each part or section of the Rules that are within Main Class will be identified as such. Typically, for DNV, Part 4 Machinery and Systems is marked Main Class. This Part includes both Electrical Installations and Instrumentation and Automation Chapters.

Additional Class is sets of rules that are optional to a vessel to document a specific type of vessel or specific capabilities of the vessel. The DP rules is a typical case of Additional Class rules, which the vessel owner has chosen to apply for his vessel.

Class Notation is another name used for Additional Class. Thus, DYNPOS-AUTR is a Class Notation, and it will be stated in the vessel’s Class Certificate.



Segregation means that two or more units of equipment are located physically separated, without stating the degree of separation. For instance, A60 is a case of segregation where there are specific requirements to the degree of protection regarding propagation of fire.

Independence, in relation to technical systems, means that one unit or system will operate without assistance from another system such that the one system will remain in operation after the other has failed. Mutual independence signifies that this will be true both ways.

Redundancy signifies that there are at least two units or systems that are able to serve a specific function, so that this function will remain operable if the one unit or system fails. See definition under 2.1.8. Thus, there can hardly be redundancy without independence. But redundancy can be achieved with a minimum of segregation, e.g. redundant components in a common cabinet.



3 DP-OPERATIONS DP operations are carried out with quite different risk potentials, from practically nothing to complete disasters. It has long been accepted that DP vessels should be chosen with consideration of how much damage they can cause if they should fail; simple vessels for simple tasks, top vessels for hazardous tasks. NMD formulated this thinking in their DP Guidelines as the “Consequence Class” concept. This has been re-formulated in the IMO Guidelines, where the vessels are equipped to comply with a defined “Equipment Class”, the higher the class, the better equipped is the vessel. The Equipment Class will then qualify the vessel for DP operations of various levels of severity.

The IMO Guidelines do not specify which Equipment Class is to be applied for a specific DP operation, say drilling or diving. Furthermore, the Classification rules do not contain requirements or advice upon this matter either.

In Norway, the Norwegian Petroleum Directorate, Oljedirektoratet, prepared revised regulations for the offshore activity which are valid from January 2002. As of January 2004, specific responsibilities have been re-assigned to the new Petroleumstilsynet, and marine operations and position-keeping are among these. Hence, the relevant requirements are found in Petroleumtilsynets documents. There are references to DP in both “Innretningsforskriften” and “Aktivitetsforskriften” and in the associated “Veiledning” for both. In the Veiledning, there is guidance attached to §81 stating that the technical requirements in IMO MSC/Circular 645 should be applied. From Guidelines “The Activities Regulations, Chapter XIV marine operations (Re Section 81 Positioning)” the following Table 1 is copied, containing recommendations for which Equipment Class to apply for typical DP operations. The full document can be found in http://www.ptil.no/regelverk/r2002/frame_e.htm (in English).

In the IMO Guidelines, it is stated that Owner and Operator shall determine which Equipment Class should be applied for a specific operation by performing a risk analysis to document all aspects of the operation. The Flag State Authorities will have the final word on the requirements placed upon the operation.

The planned DP-operations shall be subject to a risk analysis taking into account:

• Technical evaluation of vessel and DP system.

• Evaluation of planned operation, highlighting critical phases.

• Emergency procedures

• Relevant experience of Vessel and Crew.

The risk analysis document shall show that the selected vessel will provide the reliability and performance that the planned operation will require in view of risk level.



Validity of IMO Guidelines

The 1994-issue of the Guidelines is still valid. According to Sjøfartsdirektoratet, NMD, there is at this time, December 2006, no on-going action within IMO for updating the Guidelines.

The following text (all in italic at page 10, 11 and 12) are copy from the website of “Petroleum Safety Authority Norway”

Re Section 81 Positioning

In order to fulfil the requirement to marine operations as mentioned in the first paragraph, Table 1 Equipment Class should be used for vessels and facilities with dynamic positioning, with the following addition:

in the event of dynamic positioning near other floating facilities or vessels, consideration should be given, inter alia, to

a) mutual movement and different movement patterns,

b) the effect of current and noise from propellers,

c) interference with other or joint transponders,

d) varying shadow effect for antennas connected to the dynamic positioning system.



Table 1 Equipment Class

For a description of the equipment classes in this table, see IMO/MSC Circular 645, Chapter 2, Equipment Classes.

ACTIVITY Class

a) Manned underwater operations

where loss of position entails a high risk for divers or diver platforms

3

b) Other manned underwater operations

where loss of position entails risk for divers or diver platforms

2

c) Support vessels for manned underwater operations conducted from work boats

where loss of position for the support vessel has direct consequences for the work boat

2

d) Drilling and well activities where well control is handled by a facility with dynamic positioning

3

e) Facilities that produce hydrocarbons 3

f) Flotels with gangway connected

Two reference systems may be accepted for arrival and departure

3

g) Activities carried out by lifting vessels or pipelaying vessels within the safety zone Two reference systems may be accepted for arrival and departure

3

h) Other activities within the safety zone, where the vessel represents a risk to the facility

The requirement applies if the vessel exceeds the vessel size the facility is designed for with regard to withstanding a collision.

Two reference systems may be accepted for arrival and departure

2

i) Loading operations from floating storage units (FSUs) and floating production, storage and offloading facilities (FPSOs)

The requirement applies to the tank vessel

2

j) Loading operations from buoys 1

k) Other well activities

The requirement applies to well maintenance facilities if well control is handled by another facility

2

l) Shallow drilling if one does not expect to encounter hydrocarbons

1



Notes to the table

1) For dynamic position, consideration should be given to the reference systems' limitations as regards reliability, accessibility and quality.

2) High risk as mentioned in this table litera a, means the cases when the diver does not have an unrestricted return to the diving bell, or where loss of the vessel's position can lead to loss of or damage to the diving bell, and possibly the associated bottom weight.

3) The requirement to Equipment Class 3 for drilling and well activities as mentioned in this table litera d, does not apply to shallow drilling and core drilling. For shallow drilling, however, other requirements in the table may be relevant, such as the requirement to Equipment Class 2 for other activities within the safety zone without risk to health, environment and safety. Well activities that require Equipment Class 3, are, inter alia, well intervention including wireline operations. Other well activities as mentioned in this table litera k, with requirements for Equipment Class 2, where the production facility has well control equipment, may be well stimulations and unmanned underwater operations, including the use of remote-controlled subsea vessels or subsea tools.

In order to maintain the position as mentioned in the second paragraph, floating production, storage and offloading facilities (FPSOs) and floating storage units (FSUs) that offload to tank vessels, should be equipped with directional control.



4 CLASSIFICATION PRINCIPLES AND PRACTICE

The following section is guidance upon general principles and practice applied by Classification Societies, and in particular how these affect DP system. This situation is both simplified and complicated by the introduction of IMO Guidelines for Dynamic Positioning Systems. It is simplified in the sense that the various Class rules are converging upon the IMO Guidelines, as seen in the DP Rules comparisons, which has brought about so much similarity that it is possible to state equivalence between most Class Notations and IMO.

The complication is that confirmation of compliance with the IMO Guidelines is the responsibility of the Flag State Authorities, which in most cases is very difficult to obtain because few Flag States have engaged themselves in DP matters at all. The Flag State Authority has the option of delegating the responsibility of approval to the Classification Society. That is a common approach, particularly for so-called “Flags of convenience”, e.g. Liberia, Cayman Islands, but this is seldom done in the case of DP. This situation has left room for Guideline interpretations to be introduced from various non-official parties, with differing results.

In 2.1 DEFINITIONS, 2.1.2 and 2.1.6, is highlighted the difference between “DP system” and “DP-control system”; a difference that is often overlooked by involved parties. That can cause misunderstanding about the placing of responsibilities in a project. To sort that out, one should go back to classification fundamentals.

In classification work there is an overall differentiation between certification and classification. The certification is a product qualification, and classification is a vessel qualification, and there is a vast difference between being responsible for the certification of the DP-control system and the classification of the DP-system. For a new building project, the classification of the vessel, and hence the DP-system, is normally a contract between the Yard and the Classification Society. For a conversion project, the formal relationship is normally between the Ship Owner and Class, but the classification project could still be handled between the Conversion Contractor, not necessarily a yard, and Class.

Kongsberg Maritime will be responsible for the certification of the DP-control system, according to the requirements for the applicable Class Notation, assuming that the vessel will have a DP Class Notation at all. That decision is taken by the Ship Owner, and it is also the Owner who decides which notation he will adopt. It is also the Owner who decides with which IMO Class his vessel shall comply. If the contract makes reference to both Class and IMO, and there are differences, the most demanding requirement is applicable.



The Owner has the option of installing a DP-system without seeking a Class Notation, but that does not relieve the system from complying with Main Class rules. This means that the DP-control system supplier must still observe general requirements to instrumentation and automation systems, which are found in specific parts of the Main Class rules. A guidance for where to find these is given in Section 6 “ RULES FOR INSTRUMENTATION AND AUTOMATION”. The system Type Approval is intended to take care of this, as there will be no requirements to DP system configuration with respect to Main Class.

Scope of responsibility

All rules for DP are directed towards DP as a function, giving functional requirements for special equipment that in many cases are not found in other applications, and are therefore not mentioned in Main Class rules. This does not indicate exceptions to the rules. As DP is defined as an important function in a DP vessel, all equipment is subject to general rules for environmental and safety requirements. This means that attention is not limited to the DP controller, but also includes all external sensors and power equipment.

Therefore, it is most important that the contract defines the extent of system supplier responsibility. There will be grey areas that should not be taken lightly, and these situations will differ from a limited DP-control system contract and for a system that is integrated into an ICS contract. One example of this is the independent joystick that is required in most DP configurations, which in it self can be a problem. But if it is agreed that it is required, will the fact that it is independent indicate that it is not a part of the DP-control system. On the other hand, in a contract for all-inclusive thruster controls, both the joystick and manual levers would be expected to be included. In the latter case, Main Class requirements for thruster system monitoring would be included.

Power and thruster configurations are specified by Yard and/or Owner, but the DP-control system supplier may be drawn into these discussions, particularly with regard to meet the redundancy requirements for a particular classification. The various rules are not very helpful in this respect. This may not be the reason in all cases, but there is a motivation on the part of the rule-maker not to establish needless limitations in the choice of solutions. The first and best advice one can give in these situations is to study failure situations and verify that after the maximum single failure there is still a workable system configuration, and that the power and thrust resources are adequate for design specifications. That bit of advice will invariably lead to a call for an introduction to IMO Class operational limitations and Consequence Analysis.



Applicable rules for newbuildings

Newbuilding projects will span over one, two, or even more years, long enough for Classification societies to issue new and different rules. However, the project will refer to the rules in use at the time of contract signing, or even some time earlier than that. Hence, one should check which rules are applicable for each specific project, and one should be aware that Yard and Owner may have different preferences as to which rule issue to apply.

Upgrading and conversions

The Classification societies do not have clear procedures for handling upgrading and conversions which will involve more than one issue of the rules; one issue was applicable for the initial installation, and a new issue has come into force when a system change is being introduced.

The simple answer would have been that all changes should be according to current rules. That is, however, not practice. The nature and magnitude of the change will be considered; minor changes can be accepted based on the old requirements, major changes will be accepted according to current requirements. The definition of minor and major is subject to consideration.



5 COMMENTS TO THE DP RULE COMPARISON TO IMO GUIDELINES

Per December 2006, there is no updating of the IMO Guidelines of 1994 in progress. The introduction of the IMO Guidelines, which was initiated by NMD, was also the termination of the use of the former NMD “Guidelines for DP Vessels”. Until recently, NMD’s application of the IMO Guidelines has provided some additions to the IMO MSC/Circ. 645 which are described in NMD “GUIDELINES AND NOTES no. 28” of 20.10.94, and Norwegian Flag vessels were required to apply this. This document has been superseded by a direct reference to IMO MSC/Circ. 645 in new “Forskrift om ankring-/posisjoneringssystemer på flyttbare innretninger”, valid from July 2003.

The comparison includes rules from ABS, BV, DNV, LR, RINA, GL, ClassNK, and CCS. There were changes in all of these between the 2000-issue and 2002-issue of this Abstract, some of them were major changes. The overall effect was that all rules have been changed to comply with IMO Guidelines, in more or less obvious manner. Consequently, as there have been no changes in the IMO Guidelines, there are no significant changes in recent issues of the Class rules.

Revision of 2007

This revision was done with reference to the Classification rules that were valid at the end of 2006. Few changes and additions were found in the rules issued by the classification societies listed in the previous abstract.

Three more entries are made in the abstract:

• The Chinese Classification Society CCS

• The Russian Maritime Register, called “RMR” in the abstract

• The Indian Register of Shipping IRS

Position reference systems have been given particular attention in this revision. There are direct rule quotes of rule requirements for position reference systems. The number of systems has been established in the IMO Guidelines. These are in most cases followed by the societies.



The practical problem is not the quantity of systems but which type to select. The rules are written to be generally applicable, without address to any specific branch of DP-operations. Several societies includes rules for system selection; they shall be suitable for the circumstances of DP-operations, and they shall be adequately different so that they will represent a redundant configuration in any demanding situation.

ABS has issued new rules for 2004. The section for “Thrusters and Dynamic Positioning Systems” is identical to the 2002 Rule issue.

Checked against Rule edition 2007, from Internet.

DNV issued new rules in January 2004. The 2004-issue of DNV rules includes some changes for DP. The most significant would be the detail requirements for the “independent joystick” and that this joystick is to be certified.

Amendments and corrections are shown in the January 2006 version of Pt.0 Ch.1 Sec.3.

LR introduced minor changes in a revision in July 2001, but still without a requirement for Consequence Analysis, ref. Section 9. There were no changes in equipment requirements within 2003.

The only change in the Rules of July 2006 is concerning the PCR, Performance Capability Rating, which is noted in this Abstract.

BV issued new rules, of June 2000, introducing new names on the DP notations and requirements that are clearly an alignment with IMO, ref. Section 11. Since 2003, a third gyro is required for Dynapos AM R, equivalent to IMO Class 2.

Checked January 2007 with Rules-CD edition of May 2006.

RINA had adopted the new BV rules, word by word, within the 2002-issue of their rules. This is understood to be a consequence of close co-operation between these classification societies. There is a 2003-edition of the RINA rules, which is only found to contain one change. The change is deletion of the former possibility to operate in Class 3 with closed bus-tie breakers.

GL has a rule edition from 2000 containing DP rules. These rules are limited to functional requirements, which may be difficult to use in establishing a system configuration. However, the rule intentions are comparable to IMO and it is recommended to apply IMO Guidelines. Ref. Section13.

A more comprehensive set of rules has been found in the 2006-edition of GL Rules and Programs 8.0 (from purchased CD).



ClassNK The ClassNK DP rules have been in existence at least since 2000, and have not been changed since then. The rules do not refer to IMO, but are clearly an adaptation of the IMO Guidelines. No functional or numerical requirements have been found to be in conflict with IMO Guidelines and it is recommended to apply these.

NK has confirmed that there where no changes within January 2004.

The Abstract is based on the CD-ROM version of ClassNK Rules and Guidance 2006.

CCS China Classification Society

CCS has had Guidelines for DP vessels at least since 2002. CCS is included in the Abstract by use of download from Internet in December 2006.

RMR Russian Maritime Register

RMR has introduced rules for “Dynamic Positioning Systems” in their 2003-edition of their rules, where the following abstract has been collected.

In Volume 2 of the 2003-rule edition, there is a comment that the DP-rules were developed on the basis of IMO MSC/Circ. 645, the IMO DP Guidelines.

IRS Indian Register of Shipping

The Abstract is based on the IRS main rules CD-ROM, edition March-2006; Rules and Regulations for the Construction and Classification of Steel ships.

IEC standard Newbuilding specifications may list an IEC Standard as one of the regulations to observe. It can, therefore, be useful to be aware of the existence of an IEC Standard: IEC 61892-5 MOBILE AND FIXED OFFSHORE UNITS- ELECTRICAL INSTALLATIONS, where Chapter 10 is dedicated to Dynamic Positioning. This standard was issued in a Norwegian version in 2002.

The standard refers to IMO Guidelines and does not appear to escalate requirements.



Documentation of DP capability

Requirements to position keeping accuracy, or weather limits, are generally not stated by the Classification Societies, and none of the Class notations indicates anything about the power or thrust resources, except that they are to be redundant in specific notations.

LR, DNV, and BV, and hence RINA, are augmenting each Class notation with a numerical index or rating that will give an indication of resources, but only to those that are familiar with the concepts. These are:

ERN – environmental regularity number (DNV)

PCR – performance capability rating (LR)

ESKI – environmental station keeping index (BV and RINA)

The DNV version ERN will be the most familiar. In addition to being mandatory for DNV vessels, it has also been assigned to non-DNV vessels upon request. DNV will require an ERN evaluation to be submitted for approval together with other documentation from the party responsible for the classification, i.e. normally the Yard. How the Yard acquires the evaluation is their choice.

The LR version PCR is determined by LR, and it used to be voluntary. Yard and /or Owner were free to request it or not. In the LR rules of 1998, PCR was made mandatory (ref. rule Section 1-1.2 Classification notations). According to the rules, documentation is to be submitted for LR to carry out the evaluation of PCR. Providing the documentation is a Yard responsibility.

Effective from July 2003, LR has made PCR optional for DP(CM) and DP(AM), while still being compulsory for DP(AA) and DP(AAA).

The BV/RINA version ESKI is to be provided according to Owner’s choice. If the Owner wants it, he shall submit documentation to BV/RINA, which will do the evaluation.



6 RULES FOR INSTRUMENTATION AND AUTOMATION

Most of the Classification Societies have rules for instrumentation and automation in their Main Class rules, which means that they are mandatory. A list of these Rules is presented in section, 6.1 List of Class Rules for Automation Systems.

Type Approval Type Approval is generally a voluntary qualification offered by the Classification Societies. It is not known that any Society exercises mandatory Type Approval on DP-control systems, although it has been done in the past.

The basic Type Approval has been directed towards hardware, with emphasis on environmental specifications. That is still the case, but approval has been extended to include software.

6.1 LIST OF CLASS RULES FOR AUTOMATION SYSTEMS

The list contains the Main Class rules for each classification society for automation systems. Specific rules for integrated automation systems, or computer-based systems in general, are mentioned where such have been found.

ABS RULES FOR BUILDING AND CLASSING STEEL VESSEL 2007

Part 4 Vessel Systems and Machinery – updated February 2004

Chapter 8 Electrical systems

Chapter 9 Remote Propulsion Control and Automation

Ref.: www.eagle.org/rules/downloads.html

BV RULES FOR THE CLASSIFICATION OF STEEL SHIPS

Part C: Machinery, Electricity, Automation and Fire Protection

Chapter 2 Electrical Installation

Chapter 3 Automation

Part E: Additional Class Notations

Chapter 4 Integrated Ship Systems

Ref.: www.veristar.com



DNV RULES FOR CLASSIFICATION OF STEEL SHIPS January 2004

Part 4 Machinery and Systems Main Class Chapter 9 INSTRUMENTATION AND AUTOMATION

Part 6 Special Equipment and Systems – Additional Class Chapter 3 Periodically unattended machinery space E0 and ECO

Chapter 5 Integrated computer systems

Ref.: www.dnv.no

GL RULES FOR CLASSIFICATION AND CONSTRUCTION SHIP TECHNOLOGY 2006 Part 1 Seagoing Ships

Chapter 8 Electrical Installations

Chapter 9 Automation, Section 3 Computer systems

Chapter 15 Dynamic Positioning System – 2000-issue still valid

Ref.: www.gl-group.com

LR RULES AND REGULATIONS for the CLASSIFICATION OF SHIPS July, 2006

Part 5 Main and Auxiliary Machinery

Chapter 6 Steering Gears

Chapter 7 Control Engineering


Part 6 Control, Electrical, Refrigeration and Fire

Chapter 1 Control Engineering Systems

Chapter 2 Electrical Engineering

Part 7 Other Ship Types and Systems

Chapter 4 Dynamic Positioning Systems

Ref.: www.lr.org/



RINA RULES FOR THE CLASSIFICATION OF SHIPS 2003

Part C Machinery, systems and fire protection

Ref.: www.rina.org

ClassNK RULES FOR THE SURVEY AND CONSTRUCTION OF STEEL SHIPS

CD-ROM Rules and Guidance 2006

Part D Machinery Installations

Part H Electrical Installations

Ref.: www.classnk.or.jp

CCS China Classification Society RULES AND REGULATIONS FOR THE CONSTRUCTION AND

CLASSIFICATION OF SEA-GOING STEEL SHIPS

Part 3 Chapter 13 Steering Gear and Windlasses

Part 4 Chapter 2 Additional Requirements for Electrical Propulsion Installations

Part 7 Chapter 3 Requirements for the Automation of Periodically Unattended Machinery

Ref.: www.CCS.ORG.CN/EN

RMR Russian Maritime Register of Shipping RULES FOR THE CLASSIFICATION AND CONSTRUCTION OF

SEA-GOING SHIPS

Part XV AUTOMATION

2 Design of Automation Systems, Automation Components and Control Devices



IRS Indian Register of Shipping RULES & REGULATIONS FOR THE CONSTRUCTION AND

CLASSIFICATION OF STEEL SHIPS

Part 4 Main and Auxiliary Machinery

Chapter 1 General Requirements for the Design and Construction of Machinery

Chapter 6 Steering Gears

Chapter 7 Control Engineering


Ref.: http://www.irclass.org/



7 IMO CERTIFICATION IMO’s DP-Classification Guidelines. MSC/Circ. 645, 6 June 1994. (Still valid by January 2004) These guidelines for vessels with dynamic positioning systems have been developed to provide an international standard for dynamic positioning systems on all types of new vessels.

A Flag State Verification and Acceptance Document (FSVAD) for the dynamic positioning system will document compliance with the Guidelines. The purpose of a FSVAD is to ensure that the vessel is operated, surveyed and tested according to the vessel specific procedures and that the results are properly recorded.

A Coastal State may permit any vessel whose dynamic positioning system is designed to a different standard than that of these Guidelines to engage in operation.

The purpose of these Guidelines is to recommend design criteria, necessary equipment, operating requirements, and a test documentation system for the dynamic positioning to reduce the risk to personnel, the vessel, other vessels or structures, sub-sea installations and the environmental conditions while performing operations under dynamic positioning control.

The responsibility for ensuring that the provisions of the Guidelines are complied with rests with the owner of the DP-vessel.

IMO DP Equipment Class notations are as follows: Class 1 For equipment class 1, the DP-control system need not to be redundant.

Class 2 For equipment class 2, the DP-control system should consist of at least two independent computer systems. Common facilities such as self-checking routines, data transfer arrangements, and plant interfaces should not be capable of causing the failure of both/all systems.

Class 3 For equipment class 3, the DP-control system should consist of at least two independent computer systems with self-checking and alignment facilities. Common facilities such as self-checking and routines, data transfer arrangements and plant interfaces should not be capable of causing failure at both/all systems. In addition, one back-up DP-control system should be arranged. An alarm should be initiated if any computer fails or is not ready to take control.



Subsystem or Component Minimum Requirement for each Class (IMO)

CLASS 1 CLASS 2 CLASS 3 Generator and prime movers Non-redundant Redundant Redundant, in separate compartments Main switchboard 1 1 with bus tie 2 with normally open bus ties in separate

compartments, A60 Bus tie breaker 0 1 2 Distribution system Non-redundant Redundant Redundant, through separate

compartments

Power System

Power Management Note 1 No Note 1 Note 1 Thrusters Arrangement of thruster Non-redundant Redundant Separate compartments redundant

Auto control; no. of computer systems

Note 2 1 2 2 + 1 back-up

Manual control; joystick with auto heading

Note 3 Yes Yes Yes

Control

Single levers for each thruster Yes Yes Yes Pos. ref. Systems Note 9 1 3 3 whereof 1 in alternate control station

directly connected to Back-up system. Wind 1 2 3 Whereof 1 in alternate

control station

VRS Note 4 1 Note 4 2/3 3 As above

Sensors

External Sensor

Gyro compass Note 4 1 3 3 As above

UPS Note 5 1 2 2+1 separate compartment

Alternative control station for backup unit. No No Yes



IMO Guidelines Minimum requirements for each class (IMO)

CLASS 1 CLASS 2 CLASS 3

Consequence Analysis Note 6 No Yes Note 6 Yes Note 6

FMEA Note 7 No Note 7 Note 7

Installation manual/systems drawings Yes Yes Yes

FAT/CAT Yes Yes Yes

Approval of cable routing for power and control circuits

No Yes Yes

No single fault can result in more than 50% loss of DP capability

No Yes Yes

Equivalence with NMD consequence class

1 2 3

IMO CLASS KONGSBERG MARITIME SYSTEM TYPE ADDITIONAL EQUIPMENT

DP Class 1 K-Pos DP-11/12 or cPos Independent joystick w/Auto heading

DP Class 2 K-Pos DP-21/22 or K-Pos DP-31/32 Independent joystick w/Auto heading

DP Class 3 K-Pos DP-21/22 or K-Pos DP-31/32 Back-up K-Pos DP-11/12 and Independent joystick w/Auto heading



Notes and Comments

See note 8 concerning requirements for printer.

Note 1: Power management, ref. IMO Guidelines 3.2.6

There is no definite requirement for a power management system. The reference states: “If a power management is installed, adequate redundancy or reliability to the satisfaction of the Administration should be demonstrated.”

This reflects that there are power systems that have no need for power management, there is really nothing to “manage”. This should not be confused with the need for pitch/RPM reduction for black-out prevention.

Note also that there is no strict requirement for the power system to be redundant.

Note 2: Computer systems, ref. IMO Guidelines 3.4.2.5 and 3.4.2.6

Redundant computer systems should be arranged with automatic transfer of control after a detected failure in the computer currently in control. The automatic transfer of control from one computer system to another should be smooth, and within the acceptable limitations of the operations.

For Equipment Class 3, the back-up DP control system should be in a room separated by A60 class division from the main DP control station. During DP operations, this back-up control system should be continuously updated by input from sensors, position reference systems, thrusters feedback, etc, and be ready to take over control. The switch-over of control to the back-up system should be manual, situated on the back-up computer, and should not be affected by failure of the main DP control system.

Note 3: Manual control, joystick, ref. IMO Guidelines 3.4.1.7

The reference states: “It should be possible to control the thrusters manually, by individual joysticks and a common joystick, in the event of failure of the DP-control system.”

This is understood to mean the manual levers for each thrusters and the independent joystick that is required in the Class rules.



Note 4: External sensors, VRS, ref. IMO Guidelines 3.4.4.2

The reference states: “When an equipment class 2 or 3 DP-control system is fully dependent on correct signals from vessel sensors, then these signals should be based on three systems serving the same purpose (i.e. this will result in at least three gyro compasses being installed).

It is generally accepted that this requirement applies to gyro compasses. If it should also apply to VRS has to be considered in view of the chosen position reference systems and how these are dependent on roll and pitch compensation.

Note 5: UPS, ref. IMO Guidelines 3.4.2.7

The reference states: “An uninterruptible power supply (UPS) should be provided for each DP-computer system to ensure that any power failure will not affect more than one computer. UPS battery capacity should provide a minimum of 30 minutes operation following a mains supply failure.”

The requirement refers to “DP-computer system” and also “one computer”. This is understood as one UPS for each of the two DP-computer systems in Class 2, and one more for the back-up DP-control system in Class 3, ignoring the fact that each of these systems may contain more than one “computer”.

The requirement means that the large, central UPS installations found in some major automation systems may not be acceptable.

Note 6: Consequence analysis, ref. IMO Guidelines 3.4.2.4

The reference states: “For equipment classes 2 and 3, the DP-control system should include a software function, normally known as “consequence analysis”, which continuously verifies that the vessel will remain in position even if the worst case failure occurs. This analysis should verify that the thrusters remaining in operation after the worst case failure can generate the same resultant thrusters force and moment as required before the failure. The consequence analysis should provide an alarm if the occurrence of a worst case failure would lead to a loss of position due to insufficient thrust for the prevailing environmental conditions. For operations which will take a long time to safely terminate, the consequence analysis should include a function which simulates the thrust and power remaining after the worst case failure, base on manual input of the weather trend”.



Note 7: FMEA

There is no requirement for FMEA in the IMO Guidelines, the name is not even used. It is, however, difficult to see how the worst case failure can be determined without some form of failure analysis. In addition, most Classification DP rules include a requirement for an FMEA for Class 2 and 3. The few exceptions are noted in the tabular Class presentations.

Note 8: Printer, ref. IMO Guidelines 3.4.1.5

The reference states: “Alarms and warnings for failures in systems interfaced to and/or controlled by the DP-control system are to be audible and visual. A permanent record of their occurrence and of status changes should be provided together with any necessary explanations.”

This is understood as a requirement for a paper printer. A corresponding requirement is found in the DP-rules for BV, RINA, and DNV. ABS and LR have no specific requirement for an alarm printer in their DP-rules, but a general requirement should be found in their Main Class rules for automation systems. Hence, it is recommended to include the printer in any system delivered to IMO standards.

Note 9: The following is quoted from Paragraph 3.4.3 Position reference systems:

.1 Position reference systems should be selected with due consideration to operational requirements, both with regard to restrictions caused by the manner of deployment and expected performance in working situation.

.2 For equipment classes 2 and 3, at least three position reference systems should be installed and simultaneously available to the DP-control system during operation.

.3 When two or more position reference systems are required, they should not all be of the same type, but based on different principles and suitable for the operating conditions.

.4 The position reference systems should produce data with adequate accuracy for the intended DP-operation.



8 ABS CERTIFICATION BASED ON: ABS Rules for Building and Classing Steel Vessels Part 4 Chapter 3 Section 5 Thrusters and Dynamic Positioning System (Valid January 2007). http://www.eagle.org/rules/downloads.html

The Rules for DP have been unchanged since 2004.

ABS Notations are as follows:

DPS-0 For vessels which are fitted with a dynamic positioning system with centralised manual position control and automatic heading control to maintain the position and heading under the specified maximum environmental conditions.

DPS-1 For vessels which are fitted with a dynamic positioning system which is capable of automatically maintaining the position and heading of the vessel under specified maximum environmental conditions having an independent centralised manual position control with automatic heading control.

DPS-2 For vessels which are fitted with a dynamic positioning system which is capable of automatically maintaining the position and heading of the vessel within a specified operating envelope under specified maximum environmental conditions during and following any single fault excluding a loss of compartment or compartments.

DPS-3 For vessels which are fitted with a dynamic positioning system which is capable of automatically maintaining the position and heading of the vessel within a specified operating envelope under specified maximum environmental conditions during and following any single fault including complete loss of a compartment due to fire or flood.



Subsystem or Component Minimum Requirement for each Class Notation (ABS)

Note 1

DPS-0 Note 1

DPS-1 DPS-2 DPS-3

Generator and prime movers Non-redundant Non-redundant Redundant Redundant, in separate compartments

Main switchboard 1 1 1 with bus tie 2 with normally open bus ties in separate compartments

Bus tie breaker 0 0 1 2

Distribution system Non-redundant Non-redundant Redundant Redundant, through separate compartments

Power System

Power Management No No Yes Yes

Thrusters Arrangement of thruster Non-redundant Non-redundant Redundant Redundant in separate compartments.


1 1 2 2 + 1 in alternate control station.


No Yes Yes Yes

Control

Single levers for each thruster Yes Yes Yes Yes

Pos. ref. Systems Note 2 + 8 1 2 3 3 whereof 1 in alternate control station.

Wind Note 3 1 2 2 2 Whereof 1 in alternate control station

VRS Note 4 1 1 2/3 3 As above

Gyro compass Note 5 1 2 2 3 As above

Sensors

External Sensor

UPS Note 6 0 1 1 1+1 separate compartment

Alternative control station for backup unit. N/A N/A N/A Yes



Subsystem or component Minimum requirements for each Class Notation (ABS)

DPS-0 DPS-1 DPS-2 DPS-3

Consequence Analysis No No Yes Yes

FMEA Note 7 Yes Yes Yes Yes

Installation manual/systems drawings

Yes Yes Yes Yes

FAT/CAT Yes Yes Yes Yes


No No Yes Yes

Single failure not to cause a critical situation for the vessel or personnel

No No Yes Yes *includes also fire and

flooding

Equivalent to IMO class N/A 1 2 3

ABS-CLASS KONGSBERG MARITIME SYSTEM TYPE ADDITIONAL EQUIPMENT

DPS-0 cPos (See Note 1) One position reference system

DPS-1 K-Pos DP-11/12 or cPos Independent joystick w/Auto heading

DPS-2 K-Pos DP-21/22 or K-Pos DP-31/32 Independent joystick w/Auto heading

DPS-3 K-Pos DP-21/22 or K-Pos DP-31/32 Back-up K-Pos DP-11/12 and Independent joystick w/Auto heading



Notes and Comments

Requirements concerning printer are found in “IMO certification” chapters 7, note 8.

Note 1: DPS-0

This is a “dynamic positioning system” according to ABS definition. It is understood to be a joystick system with a free-standing position reference system.

Note 2: Position reference systems

There is a requirement for two pos. refs. for DPS-1, one is required for IMO Class 1.

Note 3: External sensors, Wind sensor

Compared to IMO, there is one more wind sensor in DPS-1, and one less in DPS-3.

Note 4: External sensors, VRS

The ABS rules do not state any requirement for VRS. It is recommended to apply IMO Guidelines requirements.

Note 5: Gyro compass

Compared to IMO, there is one more gyro in DPS-1 and one less in DPS-2.

Note 6: UPS

Compared to IMO, there is one UPS less in DPS-2 and DPS-3.

Note 7: FMEA

There is a requirement for FMEA in all DPS-classes. Ref. ABS DP-rules 15.1.3 and 15.1.4. The FMEA results are to be tested, ref. DP-rules 15.15.2




To assist in discussions on selection of position reference systems, the relevant rule elements are quoted:

15.7 Environment Sensor and Position Reference System

15.7.1 Vessels with DPS-0 or DPS-1 Notation

For DPS-0 notation, a position reference system, a wind sensor and a gyro compass are to be fitted. For DPS-1 notation, they are to be provided in duplicate.

15.7.2 Vessels with DPS-2 Notation

In addition to the systems in 4-3-5/15.7.1 for DPS-1 notation, a third independent position reference system is to be provided. Two of the position reference systems may operate on the same principle. A single failure is not to affect simultaneously more than one position reference system, i.e. no common mode failures.

15.7.3 Vessels with DPS-3 Notation

In addition to the requirements in 4-3-5/15.7.2 for DPS-2 notation, a third gyro-compass is to be fitted. The third gyro-compass and the third independent position reference system are to be located in the back-up control station with their signals repeated in the main control station.

15.7.4 Signal Processing

When three position reference systems are required, the control computers are to use signal processing techniques to validate the data received. When out of range data occurs, an alarm is to be given.

The requirements to position reference system are limited to an escalation in numbers, and when there are three, only two of them can operate on the same principle.

For DPS-1, the position reference systems shall be in “duplicate”. It is assumed that this means two, but not necessarily that they are equal.



9 DNV CERTIFICATION BASED ON: “Rules for Classification of Ships, Part 6 Chapter 7. January 2004, with amendments dated January 2006.

www.dnv.no

DNV Notations are as follows:

DYNPOS -AUTS Dynamic positioning system without redundancy

DYNPOS -AUT Dynamic positioning system with an independent joystick system back-up and a position reference back-up

DYNPOS -AUTR Dynamic positioning system with redundancy in technical design and with an independent joystick system back-up

DYNPOS -AUTRO Dynamic positioning system with redundancy in technical design and with an independent joystick system back-up. Plus a back-up dynamic positioning control system in an emergency dynamic positioning control centre, designed with physical separation for components that provide redundancy

General note: Previous class notation DYNPOS T has been deleted since the 2001 rule issue, and is not replaced by something similar.

In the 2001-issue, the DYNPOS “family name” had been deleted, which has only caused confusion. In the 2004-issue, “DYNPOS” has been recovered, now with a “-” in the names.



Subsystem or Component Minimum Requirement for each Class Notation (DNV)

DYNPOS-AUTS DYNPOS-AUT DYNPOS-AUTR DYNPOS-AUTRO Generator and prime movers Non-redundant Non-redundant Redundant Redundant, in separate

compartments

Main switchboard 1 1 1 with bus tie 2 in separate compartments

Bus tie breaker 0 0 1 2, 1 breaker in each MSB


Power System

Power Management Note 1 No No Yes Yes

Thrusters Arrangement of thruster Note 9

Non-redundant Note 9

Non-redundant Note 9

Redundant Redundant- in separate compartments


1 1 2 2 + 1 in alternate control station.


Note 2 No Yes Yes Yes

Control


Pos. ref. Systems Note 3 and Note 8

1 2 3 3 whereof 1 in alternate control station.


VRS Note 5 1 1 2 Note 5

3 As above

Sensors

External Sensor

Gyro compass Note 6 1 1 3 Note 6

3 Note 6

As above

UPS Note 7 0 1 2 3 whereof one in separate compartment.

Alternative control station for backup unit. No No No Yes



Sub system or compartment Minimum requirements for each Class Notation (DNV)

DYNPOS-AUTS DYNPOS-AUT DYNPOS-AUTR DYNPOS-AUTRO


FMEA and FMEA Tests No No Yes Yes


Yes Yes Yes Yes



No No Yes Yes

Single failure not to cause a critical situation for the vessel or personnel

No No Yes Yes *includes also fire and

flooding

Equivalent to IMO class: N/A 1 2 3

DNV CLASS KONGSBERG MARITIME SYSTEM TYPE ADDITIONAL EQUIPMENT

DYNPOS-AUTS K-Pos DP-11/12 or cPos

DYNPOS-AUT K-Pos DP-11/12 or cPos Independent joystick w/Auto heading

DYNPOS-AUTR K-Pos DP-21/22 or K-Pos DP-31/32 Independent joystick w/Auto heading

DYNPOS-AUTRO K-Pos DP-21/22 or K-Pos DP-31/32 Back-up K-Pos DP-11/12 and Independent joystick w/Auto heading



Notes and Comments


Note 1: Power Management. Ref. DNV DP-rules, Pt.6 Ch.7 Sec.1 Table D1

In addition to requirement for the over-all FMEA, a separate FMEA is required for the Power Management System.

Note 2: Independent joystick, ref. DNV DP-rules, Pt.6 Ch.7 Sec.2 Table C1

Requirements are introduced to ensure the independence between the joystick and the DP control system. Of particular interest is that the joystick cannot share the network of the DP control system, and it cannot be powered from one of the DP UPS’s.

The independent joystick shall be certified, ref. Pt.6 Ch.7 Sec.1 C. Certification.


There is a requirement for two pos.refs for DYNPOS-AUT, one is required for IMO Class 1.

Note 4: External Sensors, Wind sensor

Compared to IMO Class 3, there is one less in DYNPOS-AUTRO.

Note 5: External sensors, VRS, ref. DNV DP-rules

Table C1 System arrangement in the Rules Section 2 contain a foot-note stating: “Where necessary for the correct functioning of position reference systems, at least three vertical reference sensors are to be provided for the notation AUTR”

This is included to comply with IMO Guidelines 3.4.4 Vessel sensors. The definition of “necessary” is understood to be the operator’s responsibility.

Note 6: Gyro compass

Table C1 System arrangement in the Rules Section 2 contains a foot-note stating that one gyro may be substituted by a heading device based upon another principle. For DYNPOS-AUTRO, this device is not to be the gyro placed in the alternate control station.

Note 7: UPS

The certification requirement for DP-UPS has been deleted. The general certification requirement is limited to units of 100 KVA and upwards. Power input to the UPS’s shall be taken from different sides of the main switchboard. Also, the UPS for the independent joystick shall not be shared with the DP- control system.



Note 8: There are few, if any, requirements to the suitability of the position reference system for their intended/expected operational conditions. From Rule Section 3 Control System, C. Positioning Reference System, the following is quoted:

C 100 General

101 Where more than one positioning reference system is required, at least two shall be based on different principles.

This requirement will prevent system failure due to a common failure mode, which could have defeated the redundancy just in numbers. There will, however, also be possibilities for redundancy in operational suitability.

104 Positioning reference systems shall provide new position data with a refresh rate and accuracy suitable for the intended DP-operations.

This is the only reference to suitability in intended operations.

Note 9: DNV does not approve the use of two main prop and rudders without additional "thruster(s)" in the stern/aft of the vessel (tunnel, azimuth).

Pt.6 Ch.7 Section 1 GENERAL REQUIREMENTS, B. Definitions B 100 General 104 Dynamically positioned vessel (DP-vessel): A vessel which automatically maintains its position (fixed location or predetermined track) exclusively by means of thruster force.

Guidance note: In this context thruster force may include propulsion and steering (rudder) forces, see Sec.4.

Pt.6 Ch.7 Section 4 THRUSTER SYSTEMS, A. General A 200 Thruster configuration 201 The thruster configuration shall include thrust units which together will produce, at any time, transverse and longitudinal thrust, and a yawing moment.

Guidance note: The rules do not specify the number or size of thrusters to make up the configuration. The position holding capability resulting from a chosen configuration will be documented by the “environmental regularity numbers” (ern). Thrusters should be located with consideration of effects, which will reduce their efficiency, e.g. thruster-hull, and thruster-thruster interaction, and shallow-immersion effects.



202 In a thruster configuration, provided with redundancy in design and physical arrangement, there shall be transverse and longitudinal thrust, and yawing moment after any single failure.

Guidance note: Transverse thrust generated by the combined use of propellers and rudders may upon special consideration, be accepted as equivalent to a side thruster for back-up purposes, but should not be taken into consideration when calculating the first ern number, and should be proven on trials.



10 LR-CERTIFICATION BASED ON: Rules and Regulations for the Classification of Ships July 2006. Rules for the Construction and Classification of Dynamic Positioning System, Part 7, Chapter 4. http://www.lr.org/code/home.htm The 2001-issue is still valid as of July 2006, with one exception, see Note 9.

LR notations are as follows:

DP(CM) Centralised remote manual controls for position-keeping and with position reference system and environmental sensors.

DP(AM) Automatic and standby manual controls for position keeping and with position reference systems and environmental sensors.

DP(AA) Automatic and automatic standby controls for position keeping and with position reference systems and environmental sensors.

DP(AAA) Automatic and automatic standby controls for position keeping together with an additional/emergency automatic control unit located in a separate compartment and with position reference systems and environmental sensors.

General note: Section 1, General 1.1.6 Special consideration will be given where the dynamic positioning system is used primarily for purposes other than position keeping, e.g. track following. A descriptive note may be entered in column 6 of the Register Book to this effect.



Subsystem or Component Minimum Requirement for each Class Notation (LR)

Note 1

DP(CM) Note 1

DP(AM) DP(AA) DP(AAA)

Generator and prime movers Non-redundant Non-redundant Redundant Redundant, in separate compartments

Main switchboard 1 1 1 with bus tie 2 with normally open bus ties in separate compartments

Bus tie breaker 0 0 1 2


Power System

Power Management Note 2 Yes Yes Yes Yes

Thrusters Arrangement of thruster Note 11

Non-redundant Non-redundant Note 11

Redundant Separate compartments, retain at least 50% thrust in case loss of one compartment Thrust max. load diagram under DP operation is required.


1 1 2 2 + 1 in alternate control station


No Yes Yes Yes

Control



1 2 3 3 whereof 1 in alternate control station w/ a repeater in main control un it.


VRS Note 5 1 2 2/3 3 As above

Sensors

External Sensor


UPS Note 7 0 1 2 2+1 separate compartment

Alternative control station for backup unit. No No No Yes



Sub-system or component Minimum requirements for each Class Notation (LR)

DP(CM) DP(AM) DP(AA) DP(AAA)

Consequence Analysis Note 8 No No No No

FMEA No No Yes Yes


Yes Yes Yes Yes



No No Yes Yes

Single failure not to cause a critical situation for the vessel or personnel.

No No Yes Yes

Equivalence to IMO class: N/A 1 2 3

LLOYD’S CLASS KONGSBERG MARITIME SYSTEM TYPE ADDITIONAL EQUIPMENT

DP(CM) cPos (See Note 1)

DP(AM) K-Pos DP-11/12 or cPos Independent joystick w/Auto heading

DP(AA) K-Pos DP-21/22 or K-Pos DP-31/32 Independent joystick w/Auto heading

DP(AAA) K-Pos DP-21/22 or K-Pos DP-31/32 Back-up K-Pos DP-11/12 and Independent joystick w/Auto heading



Notes and Comments


Note 1: Notation DP(CM), ref. DP-rules Part 7, Chapter 4, Section 2

The notation DP(CM) is difficult to understand. It is apparently a strictly manual control mode, but one position reference is required and some control requirements are shared with the automatic classes. The higher, automatic notations are arranged as additions to the basic DP(CM) notation.

Note 2: Power Management, ref. DP-rules Section 2, 2.3.5 – 2.3.9

LR does not use the term “power management” but there are equivalent functional requirements in the referenced rule items.


Two pos. ref. systems are required for DP(AM), one more than IMO Class 1. The higher classes are equal to IMO Class 2 and 3.

Note 4: External sensors, Wind sensor, ref. DP-rules, Sections 3, 4, and 5

Compared to IMO, there is one wind sensor more in DP(AM), and one less in DP(AAA).

Note 5: External sensors, VRS, ref. DP-rules Section 2, item 2.4.6

The reference states: “Where necessary, for the correct functioning of a position reference system, a vertical reference sensor is to be provided to correct for pitch and roll of the ship. There are to be at least as many vertical reference units as there are associated position reference systems.”

LR has agreed that this formulation is not the best. It could lead to 4, 5 or maybe 6 VRS’s if each pos. ref. should have one. That is not LR intention, the intention is to judge the necessity for VRS for the different pos. ref. systems, but it is difficult to claim than any one system can do just as well without a VRS. The safe approach seems to be to follow IMO.

Note 6: External sensors, Gyro

Compared to IMO Guidelines, there is one more gyro for DP(AM), otherwise equal.

Note 7: UPS, ref. DP-rules Section 2, item 2.3.10 and Section 5, item5.1.12

There is not a specific requirement for 2 UPS’s for DP(AA) or the for the main system in DP(AAA). There is requirement for a separate UPS for the back-up DP. It is recommended to apply the IMO requirements.

Note 8: Consequence analysis

There is no requirements for Consequence Analysis for DP(AA) and DP(AAA). This is a deviation from IMO.



Note 9: Ref. Section 1, 1.2 Classification notations,

The PCR-notation, Performance Capability Rating, (equivalent to the DNV ERN) has had changes. From being introduced as voluntary for all DP-notations, it was changed to mandatory for all notations. Then it was changed to optional for DP(CM) and DP(AM) in 2005, and mandatory for DP(AA) and DP(AAA). From 2006 it is again only optional for all notations.

Note 10: The LR DP Rules are organized by adding new requirements for each class on top of the lower classes. The following rule quotes for requirements for position reference systems are included to show that the reference systems shall be selected with regard to intended vessel operations.

Section 2 Class notation DP(CM)

2.4.4 At least one position reference system, heading reference sensor and wind sensor are to be provided to ensure that the specified area of operation and heading can be effectively maintained.

2.4.5 Position reference systems are to incorporate measurement techniques suitable for the service conditions for which the vessel is intended.

2.4.6 Where necessary for the correct functioning of a position reference system, a vertical reference sensor is to be provided to correct for the pitch and roll of the ship. There are to be at least as many vertical reference units as there are associated position reference systems.

Section 3 Class notation DP(AM)

3.1.1 For assignment of DP(AM) notation, the applicable requirements of Section 2, together with 3.1.2 to 3.1.7 are to be complied with.

3.1.3 At least two position reference systems suitable for the intended service conditions and incorporating different measurement techniques, are to be provided and arranged, so that a failure in one system will not render the other system inoperative. Special consideration will be given where the use of different techniques would not be practicable during DP operations.

(There is no further mention of motion ref. units)



Section 4 Class notation DP(AA)

4.1.1 For assignment of DP(AA) notation, the applicable requirements of Sections 2 and 3, together with 4.1.2 to 4.1.9 are to be complied with.

4.1.8 At least three position reference systems incorporating at least two different measurement techniques are to be provided and arranged so that failure in one system will not render the other systems inoperative.

(There is no further mention of pos. ref. suitability or number of motion ref. units.)

Section 5 Class notation DP(AAA)

5.1.1 For assignment of DP(AAA) notation, the applicable requirements of Section 2, 3 and 4, together with 5.1.2 to 5.1.12 are to be complied with.

(There are no added requirements to sensors, not in number or suitability. There is a requirement for one of each type of sensor to be located together with the emergency control system (the back-up DP.))

5.1.9 The control/indication unit of one of the position reference systems required by 4.1.8 is to be located at the emergency control station. A repeater control/indication unit from this system is to be located at the main control station.

Note 11: The introduction for Note 10 applies. However, in Note 11 the focus is on

thrusters.

Section 3, Class notation DP(AM) 3.1.7 In the event of failure of any single thruster, the ship is to be capable of maintaining its area of operation and desired heading in the environmental conditions in which the DP system is intended to operate.



11 BUREAU VERITAS CERTIFICATION BASED ON: Rules for the Classification of Steel Ships PART E – Additional Class Notations Ch 10, Sec.6 DYNAMIC POSITIONING (DYNAPOS) http://www.veristar.com/

Issued June 2000, valid at April 2002, and reconfirmed as valid January 2004.

This edition is dated April 2005, with amendments from May 2006.

The Rules contain requirement to obtain one of the following Class Notations:

DYNAPOS SAM Semi-automatic mode. The operator’s manual intervention is necessary for position keeping.

DYNAPOS AM Automatic mode. Position keeping is automatically achieved.

DYNAPOS AM R Automatic mode. The dynamic positioning is provided with redundancy means (as defined for Equipment Class 2).

DYNAPOS AM RS Automatic mode. The dynamic positioning redundancy is achieved by using two systems or alternative means of performing a function physically separated (as defined for Equipment Class 3).

DYNAPOS AT Automatic tracking. The unit is maintained along a predetermined path.

DYNAPOS AT R Automatic tracking, with redundant systems. (As defined for Equipment Class 2)

DYNAPOS AT RS Automatic tracking, with redundant, physically separated systems. (As defined for Equipment Class 3)

The additional notations can be combined, e.g. DYNAPOS AM AT R and DYNAPOS AM AT RS.

General note

The names of the notations were changed in 2000, but the notation hierarchy has been maintained and the overall compliance with IMO Guidelines is easy to recognise. The following tabular requirements are limited to the DP notations, as there are no significant differences introduced in the tracking notations.

The DP rules have been moved from Part F, Ch. 9 to Part E, CH. 10.



Subsystem or Component Minimum Requirement for each Class Notation (BV)

Note 1

DYNAPOS SAM Note 1

DYNAPOS AM DYNAPOS AM R DYNAPOS AM RS

Generator and prime movers Non-redundant Non-redundant Redundant Redundant with separation

Main switchboard Non-redundant Non-redundant Redundant Redundant with separation

Bus tie breaker No No Yes Yes

Distribution system Non-redundant Non-redundant Redundant, with separation Redundant

Power System

Power Management Non-redundant Non-redundant Redundant Redundant with separation

Thrusters Arrangement of thruster Non-redundant Non-redundant Redundant Redundant with separation


1 Note 1

1 2 2 + 1 B/U system


Note 2 May be fitted Yes Yes Yes

Control



1 Note 1

2 3 3 whereof 1 in alternate control station directly connected to Back-up system.


VRS Note 4 1 2 2 2 As above

Sensors

External Sensors


UPS Note 6 1 1 2 3 whereof one in separate compartment.

Alternative control station for backup unit. N/A N/A N/A Yes



Sub-system or component Minimum requirements for each Class Notation (BV)

DYNAPOS SAM DYNAPOS AM DYNAPOS AM R DYNAPOS AM RS


FMEA No No Yes Yes

Installation manual/systems drawings Yes Yes Yes Yes



Note 7 No No No No

No single fault can result in more than 50% loss of DP capacity

Note 8 N/A N/A Yes Yes

Equivalent to IMO Class N/A 1 2 3

BV CLASSIFICATION KONGSBERG MARITIME SYSTEM TYPE ADDITIONAL EQUIPMENT

DYNAPOS SAM cPos (See Note 1) One Pos. Ref. System

DYNAPOS AM K-Pos DP-11/12 or cPos (Note: cPos not for DYNAPOS AT) Independent joystick w/Auto heading

DYNAPOS AM R K-Pos DP-21/22 or K-Pos DP-31/32 Independent joystick w/Auto heading

DYNAPOS AM RS K-Pos DP-21/22 or K-Pos DP-31/32 Backup K-Pos DP-11/12 and Independent joystick w/Auto heading



Notes and Comments


Note 1: The SAM rule intention is not clear; the mode is described as “semi-

automatic” with one position reference installed, but not necessarily interfaced. If it is a stand-alone reference, it will require a display that makes it possible for the operator to monitor position.

Note 2: Control, Independent joystick, ref. DP-rule 1.4.1 and 4.7.7

The first reference states: “Any dynamic positioning installation provided with an automatic control is to be additionally fitted with a manual manoeuvring control complying with the requirements of the SAM notation.”

This is understood to mean that an independent joystick is required in all BV classes, confirmed in 4.7.7.

Note 3: Position reference systems, ref. Rule 5.5.2 and Table 2

Compared to IMO Class 1, there is one more pos. ref. system in DYNAPOS AM. Equal with IMO for the higher classes.

Note 4: External sensors, Wind sensor and VRS

Compared to IMO Guidelines, there is one sensor more in DYNAPOS AM, and one less for DYNAPOS AM RS

Note 5: External sensors, gyro, ref. DP-rules 5.5.5

Compared to IMO Class 1, there is one gyro more in DYNAPOS AM, otherwise equal.

In the rule reference, there is made allowance for using “other sensors of equivalent accuracy”.

Note 6: UPS, ref. DP-rule 4.8.7

The reference states: “An uninterruptible power supply (UPS) is to be provided for each DP-computer system to ensure that any power failure will not affect more than one computer. UPS battery capacity to provide a minimum of 30 minutes operation following a main supply failure”

This is understood to be equal to IMO Guidelines.

Note 7: Cable routing

There is no requirement for approval, but according to Rule 6.1 requirements for cables and piping systems are identical to IMO Guidelines.



Note 8: The requirement of “no more than 50% of DP capacity” has been deleted from the rules amended in 2006. Such a requirement could only be met by symmetrical power/thruster systems, which are not always arranged.

Note 9: The required number of position reference systems is listed in the table. From the rule paragraph for position reference systems is quoted:

5.1 General

5.1.1 As a general rule, a dynamic positioning installation is to include at least two independent reference systems.

- For SAM notation assignment, only one reference system is required.

- For equipment classes 2 and 3, at least three position reference systems are to be installed and simultaneously available to the DP-control system during operation.

- Position reference systems are to be selected with due regard to operational requirements, in relation both to restrictions caused by the manner of deployment and expected performance in the working situation.

- When two or more position reference systems are required, they are not both/all to be of the same type, but based on different principles and suitable for the operating conditions.

5.2.1 The position reference systems are to produce data with adequate accuracy for the intended DP-operation.

The requirement for SAM notation contradicts the opening sentence. That is explained by a SAM-system not being a full DP-system.

It is clearly stated that the reference systems shall be selected with due regard to how and where they are intended to be used,

In 5.2.1 is found an allowance for selecting systems that are adequate, without overdoing it.



12 REGISTRO ITALIANO NAVALE CERTIFICATION

BASED ON: RINA Ship Rules Pt F, Ch 10, Sec 6, of 2003 SECTION 6 DYNAMIC POSITIONING (DYNAPOS) Updated from Rules 2007 edition (obtained from CD-edition)

www.rina.org

The RINA Rules of 2002 were copied directly from the Bureau Veritas Rules referred to above, using the same notation names, and the same rule text. Hence, for any questions regarding RINA project the BV information is applicable. This includes the BV introduction of the “Environmental station keeping index ESKI ”.

The 2003-issue is unchanged from the 2002-issue, with exception that operation with closed bus-tie in Class 3 operations is no longer allowed. (This change has not been introduced in the BV Rules). The Summary Table is the same as for BV.

The 2007-edition is identical to the “April 2005 with amendments May 2006” BV-Rules, used in BV Abstract above.

One difference to BV is noted, as it was in 2003.

From BV paragraph 4.2.5 is quoted:

Bus tie breakers are to be open during equipment class 3 operations unless equivalent integrity of power operation can be accepted according to Ch.3, Sec. 2, 1.1.2.

From RINA paragraph 4.2.5 is quoted:

Bus tie breakers are to be open during equipment class 3 operations.



13 GERMANISCHER LLOYD BASED ON: Rules for Classification and Construction - Ship Technology – Seagoing Ships Edition 2000 (valid at January 2004) Still unchanged on 2006 Edition on CD GL Rules and Programs 8.0 Chapter 15 Dynamic Positioning Systems www.gl-group.com GL Notations are as follows:

DP 1 For class notation DP 1, loss of position may occur in the event of a single fault.

(Ref. rule E 2.1)

DP 2 For class notation DP 2, a loss of position may not occur in the event of a single fault in any active component or system. Static components will not be considered to fail where adequate protection from damage is demonstrated and reliability is to the satisfaction of the Society. Single failures criteria apply to:

− any active component or system (generators, thrusters, switchboards, remote controlled valves, etc.)

− any static component (cables, pipes, manual valves, etc.) which is not properly documented with respect to protection and reliability.

(Ref. rule E 2.2)

DP 3 For class notation DP 3, a single failure applies to:

− items listed above for class notation DP 2, additionally any normally static components assumed to fail.

− all components in any one watertight compartment, caused by fire or flooding.

− all components in any one fire sub-division, caused by fire or flooding.

(Ref. rule E 2.3)



Quoted from Section 1. A. General:.

1. Scope

These Rules apply to dynamically positioned vessels covered by the IMO “Guidelines for Vessels with Dynamic Positioning Systems” (MSC/Circ. 645).

The functional requirements are equivalent to IMO. It is recommended to apply the IMO Guidelines equipment table accordingly:

DP 1 as Equipment Class 1



One noteworthy difference is that GL has the requirement for FMEA, but allows the alternative of documenting redundancy with a redundancy test during sea trials. Ref. note 4.



Minimum Requirement for each Class Notation (GL)

Subsystem or Compartment

DP 1 DP 2 DP 3

Generator and prime movers Non-redundant Redundant Redundant, separate compartments

Main switchboard 1 1 2 With normally open bus-ties

in separate compartments

Bus tie breaker 0 1 2

Distribution system Non-redundant Redundant Redundant through separate compartments

Power System

Power Management No If installed, adequate redundancy

If installed, Adequate redundancy

Thrusters Arrangement of thrusters Non-redundant Redundant Redundant


1 2 2 + 1 In separate compartments


Yes Yes Yes

Control

Single levers for each thruster Note 1 Yes Yes Yes

Position reference systems Note 2 1 3 3 whereof 1 connected to Back-up control system.

Wind 1 2 2 One of each connected to back-up control system

Sensors

External Sensors

VRS Note 3 1 2 2 As above



Minimum Requirement for each Class Notation (GL)

Subsystem or Compartment

DP 1 DP 2 DP 3

Gyro compass Note 3 1 2 or 3 3 As above

UPS 1 2 2+1 in separate compartment.

Alternative control station for backup unit. N/A N/A Yes

Sub-system or component Minimum requirements for each Class Notation (GL)

DP 1 DP 2 DP 3

Consequence Analysis No Yes Yes

FMEA Note 4 No Yes Yes


FAT/CAT Yes Yes Yes


No No No


N/A Yes Yes

Equivalent to IMO Class 1 2 3

GL CLASSIFICATION KONGSBERG MARITIME SYSTEM TYPE ADDITIONAL EQUIPMENT

DP 1 K-Pos DP-11/12 or cPos Independent joystick w/Auto heading

DP 2 K-Pos DP-21/22 or K-Pos DP-31/32 Independent joystick w/Auto heading

DP 3 K-Pos DP-21/22 or K-Pos DP-31/32 Backup K-Pos DP-11/12 and Independent joystick w/Auto heading



Notes

Note 1: In Rule paragraph 4.1.7 it is required that it shall be possible to control the thrusters by individual joysticks and a common joystick.

Note 2: From Rule paragraph 4.3 Position reference systems is quoted:

4.3.1 Position reference systems shall be selected with due consideration to operational requirements, both with regard to restrictions caused by the manner of deployment and expected performance for the operating conditions.

4.3.3 If two or more position reference systems are required, they shall not be of the same type, based on different principles and suitable for the operating conditions.

4.3.4 The position reference systems shall provide data with adequate accuracy for the intended DP operation.

Note 3 For Gyro, the rules have a reference to Section 2.B.4.4.2 which reads:

If, for a class notation DP 2 or DP 3 the DP control system is fully dependent on correct signals from vessel’s sensors, these signals shall be based on three systems serving the same purpose (i.e. this will result in at least three gyro compasses being installed).

If this rule is applied to VRS, the two units for DP 2 may not be adequate. It is, in any event, one short of IMO.

Note 4: There is a requirement for FMEA for DP 2 and DP 3. The requirement is followed by the following sentence:

As an alternative to a FMEA the redundancy may be documented in a redundancy test procedure which is to be verified during sea trials. Ref. F. 5.



14 NIPPON KAIJI KYOKAI (CLASSNK) BASED ON: RULES FOR THE SURVEY AND CONSTRUCTION OF STEEL SHIPS Part 4 Mobile Offshore Drilling Units, Work-ships and Special Purpose Barges Chapter 10 Positioning Systems http://www.classnk.or.jp

Current issue of the Rules is dated 2006. Chapter 10 includes positioning by mooring and DP, but does not include thruster assisted mooring.

It was confirmed by ClassNK that the 2001-issue is still unchanged at January 2004. This 2006-revision is based on the NK Rules of 2006, obtained by purchase of the NK CD-ROM of 2006.

The Rules do not refer to “IMO Guidelines”, but are quite clearly based upon these. Requirements concerning printer are found in “IMO certification” chapters 7, note 8. DP systems are to be classified into the following three categories (ref. Rule 10.2.3):

Class A DPS means a DP system that at loss of position keeping capability may occur in the event of a single failure in a single component.

Class B DPS means a DP system that a loss of position keeping capability is not to occur in the event of a single failure in any active component or system such as generators, thrusters, remote controlled valves, switchboards, etc. Normally, static components such as cables, pipes, etc., will, however, not be considered to fail where adequate protection is demonstrated, and reliability is to the satisfaction of the Society.

Class C DPS means a DP system that a loss of position keeping capability is not to occur in the event of a single failure in all components or systems. This failure is to include the following conditions specified in (a) and (b).

(a) Where the component consisting of the system is in any one watertight compartment, all components in this compartment are to be assumed to be failure due to flooding.



(b) Where the component consisting of the system is in any one fire sub-division divided by “A-60” class, all components in this sub-division are to be assumed to be failure due to fire.

The above definitions of Class A, B, C are in all intents equivalent to IMO Classes 1, 2, 3. The rule text follows familiar lines from IMO Guidelines and major class rules. The number of position reference systems and sensors are equal to IMO. The requirement for an independent joystick in case of failure of the DP control system is clearly stated for all classes. But there is no mention of auto heading in this joystick. All in all, application of the relevant IMO Equipment Class will be the recommended approach to complying with ClassNK certification.

Class A DPS as Equipment Class 1

Class B DPS as Equipment Class 2

Class C DPS as Equipment Class 3



Subsystem or Component Minimum Requirement for each Class Notation (CLASSNK)

Class A DPS Class B DPS Class C DPS

Generator and prime movers Non-redundant Redundant Redundant, separate compartments

Main switchboard 1 1 2 With normally open bus-ties

in separate compartments

Bus tie breaker 0 1 2

Distribution system Non-redundant Redundant Redundant through separate compartments

Power System

Power Management Note 1

Thrusters Arrangement of thrusters Non-redundant Redundant Redundant


1 2 2 + 1 In separate compartments


Note 2 Yes Yes Yes

Control

Single levers for each thruster

Position reference systems Note 3 1 3 3 whereof 1 connected to Back-up control system.

Wind Note 4 1 2 2 One of each connected to back-up control system


Sensors

External Sensors

Gyro compass Note 4 1 2 or 3 3 As above



Subsystem or Component Minimum Requirement for each Class Notation (CLASSNK)


UPS 1 2 2+1 in separate compartment.

Alternative control station for backup unit. N/A N/A Yes

Sub-system or component Minimum requirements for each Class Notation (CLASSNK)



FMEA No Yes Yes


FAT/CAT Yes Yes Yes


Note 5


Note 6


CLASSNK CLASSIFICATION KONGSBERG MARITIME SYSTEM TYPE ADDITIONAL EQUIPMENT

Class A DPS K-Pos DP-11/12 or cPos Independent joystick w/Auto heading

Class B DPS K-Pos DP-21/22 or K-Pos DP-31/32 Independent joystick w/Auto heading

Class C DPS K-Pos DP-21/22 or K-Pos DP-31/32 Backup K-Pos DP-11/12 and Independent joystick w/Auto heading



Notes and Comments

Note 1: Power management, ref. IMO Guidelines 3.2.6

There is no mention of Power management in the Rules.

Note 2: There is a requirement for both “single joysticks” (which is understood as levers) and an “integrated joystick” but no mention of auto heading control.

Note 3: Quoted from Rule item 10.7.7 Position reference systems

1 For all classes of the DPS. Position reference systems which are selected with due consideration to operational requirements, both with regard to restrictions caused by the manner of deployment and expected performance in working situation are to be provided with.

2. Position reference systems whose systems are of one system provided with as the DP-control system for Class B DPS are to comply with the following requirements specified in (1) to (3).

(1) At least three position reference systems are to be installed and simultaneously available to the DP-control system during operation. And they are not to be all of the same type, but based on different principles and suitable for the DP-operating conditions.

(2) The position reference systems are to produce data with adequate accuracy for the intended DP-operation.

(3) The performance of position reference systems is to be monitored and warnings provided when the signals from the position reference systems are either incorrect or substantially degraded.

Note 4: The number of sensors for Class B DPS and C DPS is given thus:

“ When the DP-control system is fully dependent on correct signals from vessel sensors, these signals are to be based on three systems serving the same purpose. This will result in at least three gyro compasses being installed where the direction of the unit is measured by the gyro compass.”

Note 5: There are requirements for cabling arrangements, but there is no mention of approval of drawings.

Note 6: The power system is to be divided on two sides of a bus-tie in the switchboard, but there is no 50% requirement.



15 CCS CERTIFICATION BASED ON: “Rules and Regulation for the Construction and Classification of Sea-going Steel Ships Guidelines on Surveys for Dynamic positioning systems (2002)

http://www.ccs.org.cn/EN

CCS Notations are as follows:

DP-1 Vessels with dynamic positioning system can keep the position and heading of the vessels under the specified environmental conditions. And at the same time, independent, concentrated manual control of vessels position and automatic heading control is to be fitted.

DP-2 Vessels with dynamic positioning system can automatically keep the position and heading of the vessel when single failure (excluding loss of a cabin or cabins) appears under the specified environmental conditions and in the specified operating fields.

DP-3 Vessels with dynamic positioning system can automatically keep the position and heading of the vessel when any failure (including entirely loss of cabin caused by fire or flood) appears under the specified environmental conditions and in the specified operating fields.



Subsystem or Component Minimum Requirement for each Class Notation (CCS)

DP-1 DP-2 DP-3

Generator and prime movers Non-redundant Redundant Redundant in separate compartments

Main switchboard 1 1 2, in separate compartments

Bus tie breaker No Yes Yes

Distribution system Non-redundant Redundant, with separation Redundant

Power System

Power Management No Installed Installed

Thrusters Arrangement of thruster Non-redundant Redundant Redundant, separate compartments


1 2 2 + 1 B/U system


Yes Yes Yes

Control

Single levers for each thruster Yes Yes Yes


2 3 3 whereof 1 in alternate control station directly connected to Back-up system.

Wind Note 2 1 2 2 Whereof 1 in alternate control station

VRS Note 3 1 2 or 3 2 As above

Sensors

External Sensors


UPS Note 5 1 1 2 whereof one in sep. comp.




Sub-system or component Minimum requirements for each Class Notation (CCS)

DP-1 DP-2 DP-3


FMEA Note 6 Yes Yes Yes


FAT/CAT Yes Yes Yes


Note 7 No No No


Note 8 N/A Yes Yes


CCS CLASSIFICATION KONGSBERG MARITIME SYSTEM TYPE ADDITIONAL EQUIPMENT

DP-1 K-Pos DP-11/12 or cPos Independent joystick w/Auto heading

DP-2 K-Pos DP-21/22 or K-Pos DP-31/32 Independent joystick w/Auto heading

DP-3 K-Pos DP-21/22 or K-Pos DP 31/32 Backup K-Pos DP 11/12 and Independent joystick w/Auto heading



Notes and Comments

Note 1: The requirement for 2 pos. ref. systems for DP-1 is one more than the IMO guidance, but quite typical for the non-redundant systems.

Note 2: The requirement for 2 wind sensor for DP-3 is one short of IMO.

Note 3: The VRS requirements are in agreement with IMO for DP-1. For DP-2, the choice between 2 or 3 VRS’s is linked to the choice of position reference system. For DP-3, two VRS’s will be one short of IMO.

Note 4: The number of gyro compasses is one short of IMO for both DP-2 and DP-3.

Note 5: The number of UPS’s is one short of IMO for DP-2 and DP-3.

Note 6: There is a requirement for FMEA for all classes. There is a description of the FMEA contents, but no indication that there is an exception for DP-1. There is a rule item 1.5.5 stating that the FMEA may be substituted by performing tests of system redundancy.

Note 7: There is no indication that approval of drawings are required, but they are included in the documentation list.

Note 8: There is no mention of power requirements after switchboard failure, although partial blackout is considered as a possible failure. For thrusters, it is required that failure of one should not cause reduced positioning capability.

Note 9: From Rule item 6.8 Position reference systems is quoted:

6.8.1 As a general rule, a DP system is to include at least two independent reference systems. For class notations DP-2 and DP-3, at least three position reference systems are to be installed and simultaneously available to the DP system during operation. When two or more position reference systems are required, they are not both / all to be of the same type, but based on different principles and suitable for the operating conditions.

6.8.3 Position reference systems are to provide data with adequate accuracy with respect to the intended DP operations.



16 RMR, RUSSIAN MARITIME REGISTER OF SHIPPING

BASED ON: Rules for the Classification and Construction of Sea-Going Ships Volume 2, Edition 2003, Part XV, Automation, 8. Dynamic Positioning Systems.

The rules being quoted are dated 2003, at which time they were introduced. They were presented as being based on IMO MCC/CIRC.645, which is generally the case. There is some uncertainty of how to determine the requirements for redundant equipment, in particular for Class 1. Notes are made to draw attention to these cases.

The characteristics of the class notations are as follows:

DYNPOS-1 is a system with minimum redundancy. The loss of position of the ship may occur in the event of a single failure.

DYNPOS-2 is a system which is to have such redundancy that a loss of position is not to occur in the event of a single failure in any active component of the system.

DYNPOS-3 is a system which is to have such redundancy that loss of position is not to occur in the event of a single failure in the following cases:

failure of any active and passive component located in different watertight compartments, or

failure of any active and passive components located in any one watertight compartment, from flooding or fire, or

failure of active and passive components in any one fire sub-division, from fire or explosion.



Subsystem or Component Minimum Requirement for each Class Notation (“RMR”) DYNPOS-1 DYNPOS-2 DYNPOS-3

Generator and prime movers Non-redundant Redundant Redundant, in separate compartments Main switchboard 1 1 with bus tie 2 with normally open bus ties in separate

compartments, A60 Bus tie breaker 0 1 2 Distribution system Non-redundant Redundant Redundant, through separate

compartments

Power System

Power Management Note 1 Thrusters Arrangement of thruster Note 2 Non-redundant Redundant Separate compartments redundant


1 2 2 + 1 back-up


Yes Yes Yes

Control

Single levers for each thruster Yes Yes Yes Pos. ref. Systems Note 3 1 / 2 3 3 whereof 1 in alternate control station

directly connected to Back-up system. Wind Note 4 1 3 3 Plus one more in

alternate control station


Sensors

External Sensor


UPS 1 2 2+1 separate compartment




Subsystem or Component Minimum requirements for each Class Notation (RMR)

DYNPOS-1 DYNPOS-2 DYNPOS-3


FMEA Note 5


FAT/CAT Note 6


Note 7 No Yes Yes


Note 8

Equivalence to IMO Class 1 2 3

RMR CLASS KONGSBERG MARITIME SYSTEM TYPE ADDITIONAL EQUIPMENT

DYNPOS-1 K-Pos DP-11/12 or cPos Independent joystick w/Auto heading

DYNPOS-2 K-Pos DP-21/22 or K-Pos DP-31/32 Independent joystick w/Auto heading

DYNPOS-3 K-Pos DP-21/22 or K-Pos DP-31/32 Back-up K-Pos DP-11/12 and Independent joystick w/Auto heading



Notes

Note 1: There is no requirement for Power Management, but if one is provided, it is to be designed with redundancy. This is not limited to the upper class notations. The following rule is common for all:

8.6.5 Where an automated power management is provided, it is to be designed with redundancy.

Note 2: It is assumed that there is no requirement for redundant thrusters in DYNPOS-1. But there is a paragraph that calls for some redundancy:

8.5.8 Class 1 DP system is to be designed with redundancy of the following components:

Thrusters with their local control systems,

Control systems of the installation (one manual control system and one computerized control system).

Note 3: Position reference systems are covered by a separate section, 8.10, from this is quoted:

8.10.1 Position reference systems for Class 1 DP-systems are to be based on the operating requirements with due regard to the acceptable performance characteristics.

8.10.2 For Classes 2 and 3 DP-systems, provision is to be made for at least three independent position reference systems based on different principles, which are to be simultaneously and coordinately available to the DP-control system during operation.

8.10.3 The position reference systems shall produce data with adequate accuracy.

Note 4: There is a requirement for additional sensors for Class 3, relative to IMO.

8.11.2 For Classes2 and 3 DP-systems, the external force signals are to come from at least three independent systems for each parameter (e.g. for heading, three gyro compasses are to be provided).

8.11.3 For Class 3 DP-systems, one group of sensors of each type, in addition to the requirements set forth in 8.11.2, is to comply with the requirements for separation thereof by “A-60” class bulkhead from other sensors

Note 5: There is no requirement for an FMEA. That is actually in agreement with IMO, where FMEA is not mentioned at all.

Note 6: The DP-rules describes “survey” both at manufacturers and yards, but not tests.



Note 7: There are no requirements for approvals, but documentation of arrangements are required.

Note 8: There are requirements to operation after partial power failure, but no quantification of remaining capability.



17 IRS, INDIAN REGISTER OF SHIPPING BASED ON: IRS Rules & Regulations for the Certification and Classification of Steel Ships Main Rules March 2006 Chapter 24 Dynamic Positioning Systems http://www.irclass.org/

IRS DP-Notations are as follows:

GS(KK) This notation may be assigned when a ship is fitted with centralized remote manual controls for position keeping.

GS(SK) This notation may be assigned when a ship is fitted with automatic controls for position keeping and with manual standby controls.

GS(SS) This notation may be assigned when a ship is fitted with automatic controls and automatic standby controls for position keeping.

The DP rules do not contain any reference to the IMO Guidelines and the following table of comparison with IMO is followed by a number of Notes with details on differences between IRS and IMO.

The first notation GS(KK) is understood as a manual joystick control mode, according to the above definition. It does include requirement for one gyro compass, without stating a requirement for automatic heading control. There is requirement for at least one position reference system, and associated VRS if that is considered necessary.

GS(SK) is placed in the table for comparison with IMO Class 1 and GS(SS) is compared to IMO Class 2. There are no requirements in the rules that indicate motivation for compliance with IMO Class 3.



Subsystem or Component Minimum Requirement for each Class Notation (IRS)

Note 1 GS(KK) Note 1

GS(SK) GS(SS)

Generator and prime movers Non-redund. Non-redundant Redundant Main switchboard Non-redund. Non-redundant Redundant Bus tie breaker No No Yes Distribution system Note 2 Non-redund. Non-redundant Redundant

Power System

Power Management No No No Thrusters Arrangement of thruster Note 3 Non-redund. Non-redundant Redundant


1 1 2


Note 4 1 (No) 1 (Yes) No

Control

Single levers for each thruster Note 5 Pos. ref. Systems 1 2 3

Wind 1 2 2

VRS Note 6 1 2 2

Sensors External Sensor

Gyro compass 1 2 2

UPS Note 7

Alternative control station for backup unit. N.A.

N.A. N.A.



Subsystem or Component Minimum requirements for each Class Notation (IRS)

GS(KK) GS(SK) GS(SS)

Consequence Analysis No No Yes

FMEA No No Yes


FAT/CAT Yes Yes Yes


Yes Yes Yes


No No Yes

Equivalence to IMO Class

Note 4

N.A Class 1 Class 2

(Note 4)

IRS CLASS KONGSBERG MARITIME SYSTEM TYPE ADDITIONAL EQUIPMENT

GS(KK) cPos (Note: See definition of GS(KK).) One position reference system

GS(SK) K-Pos DP-11/12 or cPos Independent joystick w/Auto heading

GS(SS) K-Pos DP-21/22 or K-Pos DP-31/32 See Note 4



Notes

Note 1: GS(KK)

See definition of GS(KK) and our interpretation.

Note 2: There is a requirement under Distribution Arrangements that reads:

3.4.1 Thruster auxiliaries, control computers, reference systems and environmental sensors are to be served by individual circuits.

That can be understood as a requirement for redundant distribution.

Note 3: There is a requirement that calls for duplication of power to thruster auxiliaries:

2.2.3 Steerable thrusters and thrusters having variable pitch propellers are to be provided with two independent supplies of motive power to the pitch and direction actuating mechanisms.

This is valid for all class notations.

Note 4: There is a general requirement for auto heading control, including the joysticks.

There is no mention of the back-up joystick as required for IMO Class 2.

Note 5: There is no mention of individual lever control of thrusters. This is assumed to be an oversight.

Note 6: There is no firm requirement for VRS. There is a general rule requirement that VRS shall be installed “if applicable”.

4.3.4 Vertical reference sensor(s) are to be provided, if applicable, to measure the pitch and roll of the ship.

Note 7: There is only one reference to UPS, under the section for Auxiliary supplies:

3.5.1c When the control system incorporates volatile memory it is to be supplied via uninterruptible power supplies (UPS).

new class notation abstract_spec-2002_v2

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