Yes. And when on shore power the battery switch must remain on for the DC electrics to work.My boat does not have a charger that charges the batteries while on shore power. I have a portable one that I connect occasionally but nothing hard wired. The PO mentioned this now I know why. I'm assuming there is a built in charger that stays hardwired to the batteries and powered by shore power. I need to install one of these. Does that sound correct?
It doesn't make any difference. The lights always run off the batteries. When the shore power's on, it's running the charger, not the 12 volt system. In order for your 12v DC system to operate, the RED battery selector switch needs to be on. When the battery switch is on, but the charger is off, as when you're out sailing, the DC system works solely off the batteries. When you get back to the dock and hook up the shore power, the battery charger can now be activated, where it slow the depletion of the batteries. But.... even with the battery charger operating, the 12 system still runs off the batteries.My boat does not have a charger that charges the batteries while on shore power. I have a portable one that I connect occasionally but nothing hard wired. The PO mentioned this now I know why. I'm assuming there is a built in charger that stays hardwired to the batteries and powered by shore power. I need to install one of these. Does that sound correct?
Do it soon. It sounds like this boat is new to you? How old are your batteries and what are they? Your engine alternator and/or a portable automotive-style charger are not charging your batteries fully. You will be killing those batteries slowly (or rapidly - depending upon your usage). In any event, if you think that you may also be purchasing new batteries any time soon, do the reading up front and learn the best way to care for your batteries. They are discharged and re-charged much differently than they are with a car or even a power boat.My boat does not have a charger that charges the batteries while on shore power. I have a portable one that I connect occasionally but nothing hard wired. The PO mentioned this now I know why. I'm assuming there is a built in charger that stays hardwired to the batteries and powered by shore power. I need to install one of these. Does that sound correct?