I have a Catamaran with two seperate 12V starting batteries - one for each engine - along with a house bank consisting of 6 6V Trojan deep cycle batteries. I also have 2 alternators - one on each engine.
Is it best to have both the starting batteries allocated to the "1" position then the house bank designated to the "2" position? Or, should I find a way to isolate the two starting batteries from each other? Is there a switch that offers 1, 2, 3, ALL and OFF positions? And if so, would that be the most desirable for my setup?