Main source of electrical power and main switchboards: ships of Class III
(i)44. In every ship of Class III a main source of electrical power shall be provided of sufficient capacity to supply all the services referred to in regulation 43(3)(a) and (b).
(ii)The main source of electrical power shall be arranged so that such services can be maintained regardless of the speed and direction of rotation of the propulsion machinery or shafting.
(iii)The main source of electrical power shall consist of at least two generating sets, such that auxiliary services essential for the propulsion and safety of the ship can be operated when any one of the sets is out of service.
(iv)Arrangements shall be made which will safeguard such sets from being rendered inoperative in the event of the partial flooding of the ship’s machinery space through leakage from a damaged compartment or otherwise.
(2) In any ship with only one main generating station, the main switchboard shall be located in the same space as the main generating sets. Where there is more than one main generating station and only one main switchboard, that switchboard shall be located in the same space as one of the main generating stations. Where other essential features of the ship render the application of these requirements impracticable the provision of equivalent arrangements may be permitted. For the purpose of this paragraph an environmental enclosure for the main switchboard, such as a machinery control room fitted within the main boundary of the space, does not provide separation between the generating sets and switchboards.
Additional requirements for ships of Class III constructed on or after 1st September 1984
(3) (a) Load shedding or other equivalent arrangements shall be provided to protect the generators required by paragraph (1) against sustained overload.
(b)Where two or more generating sets may be in operation at the same time for maintaining the auxiliary services essential for the propulsion or safety of the ship, provision shall be made for the sets to operate in parallel.
(c)Any transforming equipment supplying an electrical system referred to in this regulation shall be arranged to ensure the same continuity of supply as that required for generating sets by this regulation.
(4) The arrangement of the generating sets required by paragraph (1) shall be such that with any one of the sets out of service—
(a)normal operational conditions of propulsion and safety of the ship and minimum comfortable conditions of habitability including those for cooking, heating, domestic refrigeration, mechanical ventilation, sanitary and fresh water can be maintained; and
(b)from a dead ship condition, the remaining sets are capable of providing the electrical services necessary to start the main propulsion plant. The emergency source of electrical power may be used for this purpose if it is capable of simultaneously supplying the emergency supplies required by these Regulations or is capable of supplying such services when combined with any other source of electrical power.