I did a search and didn’t find a concise answer to my question about the master power switch. If I hit the master power switch do I need to turn the dual battery switch to the off position when the boat is not in use?
You do not need to kill the dual battery switch if you don't want too. I turn mine off at dual battery switch just eliminate any chance of a dead battery . I also have a battery tender installed that is on when boat is not in use.
Not an electrical expert and have not seen a Bennington wiring diagram, but...
Killing the main battery switch will ensure nothing drains your batteries. Engine will not start and nothing will/should work.
Master power switch at helm kills your accessories, but if the battery switch is "on" your engine will trim and start. Fuel pump and gauges will power up and perhaps some other systems wired prior to the master switch or powered from the alternator on the motor.
My boat has one, but personally don't have a use for it since I always switch off power at the battery.
100% the above two comments. Shut off the battery at the battery switch. There are still open circuits if you just use the helm switch. And as Potomacbassin’ stated, if ANYTHING else is wired prior to the helm master switch, they will still potentiall draw power. Ask me how I know....
Use that battery off switch and then you have zero worries.
Actually, they wired the memory for the radio directly to the battery bypassing the switch. Our boat can sit for long periods and the start battery was dead. The house battery was ok and I got the boat started but it killed the start battery. I disconnected the memory wire. We can only get one FM station so I just hit search and it finds it.
Once I get the boat on the water I never turn off the helm switch. Never had a problem. Of course I'm on a lift next to my house, so if there ever was an issue I'd just need to top off. I also keep the 1+2 switch on one battery or the other (cycle every few times out) so I always have power.