the reg power still needs to come from the battery that starts the motor
. a reg should have a b+ and a sense + like a balmar
mc 614 does. (as well as ign wire)
the reg will power up off the engine
battery. read 10v on the sense. and start charging
the house full blast. once the house bank gets high enough the echo charger
will kick in.
if you have an old reg that uses the power wire as the sense. consider replacing it. also consider replacing the 1,2, all switch. and separate the house and engine battery properly.
with a 1,2,all swtich I would likly have the sense, alt + and reg + all to the common. at bare min the reg b+ needs to.
get a blue sea add a battery kit. run the alt to the house, reg sense to the house batt, and reg power to the engine batt.