
Originally Posted by
MLA
Ditch,
during the normal season when the boat is used on a regular basis, there will typically not be a need to recharge the main cranking battery on 99% of boats with properly configured dual battery setup. The real advantage to having and dual bank charger thats hooked to both the main and the house bank, is when the boat is put up for the winter. A quality marine on-board charger will maintain both banks during the off season.
You would have to consult the particular charger manufacturer about combining the main and house outputs of a 2-bank charger. Many have dedicated main and house outputs, more amps going out on the house side as its typically the one that will be run down. Some sense the level of each bank and distribute on demand. Not sure how that might work with the 2 house batteries wired in parallel. You could go with a single bank, or put in a simple ON/OFF switch in between the 2 house bank batteries and open the switch for charging.