Eliminate Battery Isolators

[crayiii]

On our catamaran we have a Cristec battery isolator in each engine to charge the start batteries as well as the house bank.

I would like to remove the house bank from direct alternator charging and instead use a DC/DC charger.

Can I just remove the cable from the isolators that go to the house bank and connect them to the DC/DC chargers and leave the isolators in place for the start batteries?

Would it be better to remove the isolators and have the alternator cable connect directly to the start batteries (fused)?

My reasoning for leaving the isolators is to go back to the factory wiring in case there is ever an issue with a DC/DC charger.

[Davidasailor]

Just curious why you’d like to replace the isolator with the DC/DC charger?

You should be fine leaving just the start battery connected to the isolator. We have 2 isolators - the alternator goes to the input of both. The outputs of the first one go to the house and start banks. The second one has one output going to the thruster bank, and its other output is empty.

[crayiii]

Originally Posted by Davidasailor

Just curious why you’d like to replace the isolator with the DC/DC charger?

You should be fine leaving just the start battery connected to the isolator. We have 2 isolators - the alternator goes to the input of both. The outputs of the first one go to the house and start banks. The second one has one output going to the thruster bank, and its other output is empty.

I don’t want the house batteries sitting at 14.2 volts for hours when we’re motoring.