onboard battery charger concept

[snapshotmd]

I'm confused about how an onboard battery charger works.  I see that they have to be plugged into 120VAC... So how does it charge the batteries while on the water?

Do i have to have a power inverter DC-AC to operate and dedicate a battery to power the inverter?

[TommyBass]

If Im thinking about what your thinking about than yes... they do have to be plugged into a 120v outlet.  The term "onboard charger" simply means you permenantly mount the charger to your boat and wire it to your battery (1 bank) or batteries (2 batteries = 2bank, 3batteries = 3 bank).  They make charging easier so when your done for the day and park your boat, whether it be trailered at your garage or in a marina slip, all you have to do is plug the one plug in on your boat into a 120 v outlet and it charges all of your batteries.  Saves you the time of having to carry around a charger and move it from battery to battery etc.

[Long Mike]

If you want to charge the batteries while on the water, you are going to need a really, really, really long extension cord.   ;D

[snapshotmd]

That makes sense.  The way it sounded on some of the things I've read made it sound like they're continuously charging while the charging batteries were in use.  Maybe it was solar battery chargers.

[bass or bass ?]

I have a 12" X 18" solar battery charger mounted on my boat. It slowly charges batteries while parked in my driveway without the weight of a charger. It also returns a small amount of charge to the batteries while on the water, but obviously not as much as is being used.     Happy fishing.

~B.A.S.S.~N.A.F.C.~BoatU.S.~N.R.A.~A.M.A.'

[Casey]

I am currently wondering the same thing.  I am thinking about purchasing one of the MinnKota DC charging systems that pull power from your boats alternator to charge your trolling motor batteries.  

[NBR]

Chances are your big motors alternator won't put out enough amps to help much unless you do a lot more running than fishing.