Isolator for house battery

Hello All-
I am looking for some opinions on whether I should install an isolator in my boat to charge my house battery while the big motor is running. I have wired my boat up to have both Main and Kicker run off of the starting battery and then electronics, pumps, lights etc to run off of the house battery. I do have a 3-bank onboard charger (2 for trolling motor batteries and 1 for House battery) that will get plugged in every night when on fishing trips. In your opinion is installing an isolator on the boat overkill? We do fish some big water and I don’t like the idea of running without my electronics, especially at night. Thanks for any insight your willing to share.

It’s not overkill to want electronics and safety on big water. Not an isolator but Minnkota has a charger that takes overflow from your starting battery downstream to other batteries. This is their DC series.

Essentially it senses voltage on your starting battery. When the motor has the starting battery over a certain voltage then the MK DC charger will then allow amps to charger other batteries.

You can buy it in a 1, 2, or 3 bank version. ex. If you did the MK DC 1 then you could focus all the extra amps just to your house battery. If you did the MK DC 3 then you could help fill both your house and 2 tm batteries.

Great option to help while you’re on the water. This supplements but does not replace your onboard charger.

You could just install a diode in line from your starting battery to your house battery as diodes only let current flow one way.

A Perko switch allows you to choose battery A, battery B or both. On runs with the big motor and the “Both” selected on the switch both batteries are getting charged.

Just install a battery solenoid, when open it will charge your house battery. When closed it will not drain starting battery.