Installation of a dual battery system in a boat begins by installing the battery switch in a location where you can easily reach. Connect the positive port of the engine to the number one position on the switch and the positive port from the house battery to the second position to the switch. Connect the negative ports, and add additional battery housing to increase the duration of the charge.Continue Reading
Install the battery switch near the battery installation at a place where you can quickly locate and reach. The appropriate place to mount the switch is inside the engine compartment, directly to the hull. Connect the switch well using the hardware that comes with the switch.
Use the same battery position, and connect the positive port from the engine battery to the first position on the switch plate. Connect the positive port from the house battery to the second position on the switch plate. Connect the neutral ports of both batteries to each other and that of the engine battery to the engine.
Connect the neutral port of the second battery to the positive port of the current house battery to an additional battery. Add another battery to the bank, and connect it to the other battery in a parallel configuration.