Regal 3300 Owner's Manual page 122

CHAPTER 4
Battery Management Panel
Your boat features a battery management panel located at the starboard
cockpit area. This battery management panel includes twin battery
switches. The port on/off style battery switch controls the house battery functions.
The circuit is protected by a 150 amp circuit breaker located close to
the sump battery bank.
Never turn off the engine's battery switch while the engine is
running. The engine's alternator and electronics could be damaged.
The starboard battery switch controls both engine cranking batteries. Notice
that the starboard engine battery switch can be switched to "combine
batteries" which will permit cranking either engine with both engine
batteries simultaneously. This can be useful if one of the batteries is
discharged. Be sure to reset the switch to ON after the engines have
started.
Notice the four breakers at the panel center. These breakers protect the
distribution panels located at the helm and in the cabin. Also, note there
are additional equipment breakers at the top port and starboard panel.
Should a breaker "trip" or fuse "blow" determine the cause of the
problem before resetting the breaker or replacing the fuse. When
replacing breakers and fuses use the correct type and amperage.
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