G'day, Mate. I don't have the Blue Sea version, but have you similiar relays to combine the
batteries. There are times, despite the different battery voltages that I want to have them combined and like the ability to do this manually. For example, I can run my fridge/freezer using an
inverter on the house bank. The
wind dies, we end up motoring and I can then combine the
batteries to put the
engine alternator amps into the hosue bank. The house bank voltage is usually below 12.3 volts during this operation and the automatic relays usually prevent them from combining. Cheers.