46 CFR § 28.355
Main source of electrical power
April 15, 2021
(a) Applicability. Each vessel that relies on electricity to power any of the following essential loads must have at least two electrical generators to supply these loads:
(1) The propulsion system and its necessary auxiliaries and controls;
(2) Interior lighting;
(3) Steering systems;
(4) Communication systems;
(5) Navigation equipment and navigation lights;
(6) Fire protection or detection equipment;
(7) Bilge pumps; or
(8) General alarm system.
(b) Each generator must be attached to an independent prime mover.