46 CFR § 28.375 - Emergency source of electrical power.
(a) Each vessel must have an emergency source of electrical power which is independent of the main sources of electrical power and which is located outside the main machinery space.
(b) The emergency source of electrical power must be capable of supplying all connected loads continuously for at least 3 hours.
(c) Except as provided in paragraphs (d) and (e) of this section, the following electrical loads must be connected to the emergency source of power:
(1) Navigation lights;
(2) Steering systems;
(3) Bilge pumps;
(4) Fire protection and detection systems, including fire pumps;
(5) Communication equipment;
(6) General alarm system and;
(7) Emergency lighting.
(d) A vessel less than 36 feet (11.0 meters) in length need only supply communication equipment by an emergency source of electrical power if flashlights are provided.
(e) A vessel less than 79 feet (24 meters) in length which is not dependent upon electrical power for propulsion, including propulsion control systems or steering, need only supply emergency lighting, navigation equipment, general alarm system, and communication systems by the emergency source of power.
(f) Where the emergency source of power is a generator, the generator prime mover must have a fuel supply which is independent of other prime movers.
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