Everything is 12v, I have two starter batteries, one for each engine charging from an alternator on each engine. Also a bank of 4 deep discharge batteries for house. Each starter battery is connected to house via 1/2/Both switches. Charge sources are shore power via charger, solar trickle feeding with no controller, and the two alternators.
Ideally I would like to know the state of each individual battery.
Best: do away with the 1/2/both battery switch. Each starter battery/alternator is isolated from each other and the house bank. All 4 house batteries connected in parallel. Each starter battery feeds the house bank via its own DC-DC charger.
Each battery bank can be fitted with its own battery monitor.
Add a solar charge controller for the solar panels. Don't connect them directly to any battery bank.
If you need a connection between house bank and starter battery for emergency, then a second DC-DC charger can be set up to feed the other way.
