Emergency sources of electrical power

(1) A self-contained emergency source of electrical power shall be provided. (2) The emergency source of electrical power associated transforming equipment, if any, and emergency switchboard shall be located above the uppermost continuous deck and shall be readily accessible from the open deck. They shall not be located forward of the collision bulkhead, except where permitted by the Administration in exceptional circumstances. (3) The location of the emergency source of electrical power, associated transforming equipment, if any, and emergency switchboard in relation to the main source of power, associated transforming equipment, if any, and main switchboard shall be such as to ensure to the satisfaction of the Administration that a fire or other casualty in the space containing the main source of electrical power, associated transforming equipment, if any, and main switchboard, or in any machinery space of category A will not interfere with the supply, control and distribution of the emergency source of (4) Provided that suitable measures are taken for safeguarding independent emergency operation under all circumstances, the emergency generator may be used, exceptionally, and for short periods, to supply non-emergency circuits. (5) The electrical power available shall be sufficient to supply all those services that are essential for safety in an emergency, due regard being paid to such services as may have to be operated simultaneously. The emergency source of electrical power shall be capable, having regard to starting currents and the transitory nature of certain loads, of supplying simultaneously at least the following services for a period Merchant Ships (Registration) 153 specified hereinafter, if they depend upon an electrical source for their operation– (a) for a period of three hours, means for illumination required by regulation 94(1)(b); (b) for a period of eighteen hours, emergency lighting– (i) in all service and accommodation alleys, stairways and exists; (ii) in containing propulsion machinery used for navigation, if any, and main source of electrical power and their control positions; (iii) in all control stations, machinery control rooms, and at each main and emergency switchboard; (iv) at all stowage positions for fireman’s (v) at the steering gear, if any; and (vi) at the emergency fire pump and its control position; (c) for a period of eighteen hours– (i) the navigation lights and other lights required by the 1972 regulations; and (ii) the VHF, MF and MF/HF radio installations required by Part VI of these Regulations or chapter IV of the 1974 SOLAS Convention; and Merchant Ships (Registration) 154 (d) for a period of eighteen hours– (i) all internal communication equipment as required in an emergency; (ii) the fire detection and fire alarms systems; and (iii) operation of emergency fire pumps, if electrically operated. (6) In a ship propelled by mechanical means regularly engaged on voyages of short duration, the Administration, where satisfied that an adequate standard of safety would be attained, may accept a lesser period than the eighteen-hour period specified in subregulation (5)(b) and (5)(c), but in no case less than three hours. (7) The emergency source of electrical power may be either– (a) an accumulator battery capable of carrying the emergency electrical load without recharging or excessive voltage drop; or (b) a generator driven by a suitable prime mover with an independent fuel supply and starting to the satisfaction of the Administration. (7) Where the emergency source of power is an accumulator battery, it shall be automatically connected to the emergency switchboard upon failure of the main source of electrical power. Where automatic connection to the emergency switchboard is not practical, manual connection may be acceptable to the satisfaction of the Administration. (8) Where the emergency source of power is a generator, it shall be automatically connected to the emergency switchboard within 45 s of the loss of the main source of electrical power. It shall be driven by a prime mover with an independent fuel Merchant Ships (Registration) 155 supply having a flashpoint not less than 43°C. Automatic starting of the emergency generator will not be required where a transitional source of power to the satisfaction of the Administration is provided. (9) For ships of less than 24m in length engaged on voyages of not more than 20 miles from the nearest land, the Administration may waive any of the requirements of this section which are found to be impracticable. G. Machinery and Electrical Installations for Ships Propelled