Section 76.27-25 - Power and circuitry(a) The power supply and emergency power supply for all fire detection and alarm systems must be in accordance with 46 CFR chapter I, subchapter J (Electrical Engineering). At the end of the required period for which the fire detection and alarm system must remain operable under emergency power, the system must remain capable of operating all audible and visual fire alarm signals for an additional period of 30 minutes.(b) All wiring and electrical circuits and equipment must be in accordance with 46 CFR chapter I, subchapter J (Electrical Engineering).(c) All fire detection and alarm systems must monitor power supplies and circuits necessary for the operation of the system during loss of power and fault conditions.