BS IEC 61892-5:2000 pdf download – Mobile and fixed offshore units — Electrical installations — Part 5: Mobile units.
3.10
semiconductor convertor
static device using semiconducting elements to convert electric energy from one state to another
3.11
steering gear control system
equipment by which orders are transmitted from the navigating bridge to the steering gear power units
NOTE Steering gear control systems comprise transmitters, receivers, hydraulic control pumps and their associated motors, motor controllers, piping and cables, etc.
3.12
steering gear power unit (electric steering gear)
electric motor and its associated electrical equipment used to operate the steering gear
3.13
steering gear power unit (electrohydraulic steering gear)
electric motor and its associated electrical equipment and connected pump used to operate the steering gear
4 General requirements
4.1 In every mobile unit in which electric power is used for the services necessary for the safety of the unit, the generators, switchgear, motors and associated controlgear for such services, with the exception of machinery In the platform of semi-submersibles, shall be so situated or arranged that they continue to operate satisfactorily in the event of partial flooding by bilge water above the tank top in the space in which they are situated. The design criterion for partial flooding shall be assumed to be a depth of water 1,12(11 beam but not exceeding a depth of 1,5 m except where this requirement is impracticable for horizontally mounted propulsion generators and motors. In such circumstances the machine enclosures shall, at least, be watertight to the underside of the shaft.
4.2 Rotating machines shall be installed to minimise the effects of motion. The design of bearings of all machines and the arrangement for their lubrication shall be adequate to withstand the motions encountered in heavy weather and operation for prolonged periods at the list and trim specified in clause 5 without the spillage of oil.
4.3 Conductors and equipment shall be placed at such a distance from each magnetic compass or shall be so disposed that the interfering external magnetic field is negligible; that is. the total singular deviation shall not exceed 30 minutes when any combination of circuits is switched on and off.
4.4 Where the total installed electrical power of the main generators exceeds 3 MW the busbars or the main switchboard shall be subdivided Into at least two parts. The subdivision may be effected by removable links, circuit-breakers or other suitable means so that the main generators and any supplies to duplicated services which are directly connected to the busbars are, as far as is practicable, equally divided between the sections.
3.10 semiconductor convertor static device using semiconducting elements to convert electric energy from one state to another 3.11 steering gear control system equipment by which orders are transmitted from the navigating bridge to the steering gear power units NOTE Steering gear control systems comprise transmitters, receivers, hydraulic control pumps and their associated motors, motor controllers, piping and cables, etc. 3.12 steering gear power unit (electric steering gear) electric motor and its associated electrical equipment used to operate the steering gear 3.13 steering gear power unit (electrohydraulic steering gear) electric motor and its associated electrical equipment and connected pump used to operate the steering gear 4 General requirements 4.1 In every mobile unit in which electric power is used for the services necessary for the safety of the unit, the generators, switchgear, motors and associated controlgear for such services, with the exception of machinery In the platform of semi-submersibles, shall be so situated or arranged that they continue to operate satisfactorily in the event of partial flooding by bilge water above the tank top in the space in which they are situated. The design criterion for partial flooding shall be assumed to be a depth of water 1,12(11 beam but not exceeding a depth of 1,5 m except where this requirement is impracticable for horizontally mounted propulsion generators and motors. In such circumstances the machine enclosures shall, at least, be watertight to the underside of the shaft.