Sec.  80.860   Reserve power supply.

   (a) When the main power supply is not on the same deck as the main
   wheelhouse or at least one deck above the vessel's main deck, a reserve
   power supply must be provided and must be so situated. The location of the
   reserve power supply must be located as near to the required transmitter and
   receivers as practicable and meet all applicable rules and regulations of
   the United States Coast Guard.

   (b) The reserve power supply must be independent of the propelling power of
   the ship and of any other electrical system, and must simultaneously
   energize the radiotelephone transmitter at its required antenna power, the
   required receivers, the emergency light and the automatic radiotelephone
   alarm signal generator. The reserve power supply must be available at all
   times.

   (c) The reserve power supply may be used to energize the bridge-to-bridge
   radiotelephone and the VHF radiotelephone installation required by  Sec. 80.871.

   (d) All circuits connected to the reserve power supply must be protected
   from overloads.

   (e) Means must be provided for charging any batteries used as a reserve
   power supply. A continuous indication of the rate and polarity of the
   charging current during charging of the batteries must be provided.

   (f) The cooling system of each internal combustion engine used as a part of
   the reserve power supply must be adequately treated to prevent freezing or
   overheating consistent with the season and route to be traveled by the
   particular vessel involved.

   (g) The reserve power supply must be available within 1 minute.

   [ 51 FR 31213 , Sept. 2, 1986;  52 FR 35246 , Sept. 18, 1987]