1.3 Definitions
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Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC/Circular.645 – Guidelines for Vessels with Dynamic Positioning Systems – (Adopted on 6 June 1994) - Annex - Guidelines for Vessels with Dynamic Positioning Systems - 1 General - 1.3 Definitions

1.3 Definitions

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

  1.3.1 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.

  1.3.2 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.

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

  1.3.4 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 routeing).

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

  • .1 thrusters 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 routeing.

  1.3.6 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 routeing.

  1.3.7 Computer system means a system consisting of one or several computer including software and their interfaces.

  1.3.8 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.

  1.3.9 Flag State Verification and Acceptance Document (FSVAD) means the document issued by the Administration to a DP-vessel complying with these Guidelines. (See Appendix for model form.)

Parent topic: 1 General
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