Make sure your cabling is the correct gauge double check your wiring and measure the voltage. Most solar controllers are single output so charge only one battery bank.

Parallel Battery Bank Wiring Diagram Solar Battery Solar
Marine battery bank wiring diagram. Two battery boat setup with wiring diagram. If you have any questions or doubt about how to use install or wire any battery switch consult a certified marine electrician. Trolling motor wiring diagrams while small and medium trolling motors use a single 12v marine battery larger trolling motors use larger 24v and 36v systems and require 2 or 3 marine batteries accordingly. Weve changed the diagram a bit now to show the start battery running through our new marine battery switch. For more detailed wiring guidelines please consult a qualified marine electrician or one of the many. A double pole onoffcombine battery switch like this one is a great choice for a single engine two battery boat wiring system.
The following basic wiring diagrams show how batteries battery switches and automatic charging relays are wired together from a simple single battery single engine configuration to a two engine one generator and four battery bank system. Battery disconnect switches help manage the overall use of electrical power on board. Draw a diagram to help with your installation especially for larger battery banks. I allows your house and start battery to remain isolated except for emergency conditions. But adding on off switches to the circuit you can force the alternator to charge the battery you want charged. This dual battery setup for boats uses the blue sea add a battery kit for charging marine batteries.
These larger motors and multiple batteries are wired in a series pattern and optimally the circuit breaker sho. The wiring diagram below is taken from our dual output controller manual and illustrates the basic wiring required for a two panel system a dual output controller and two battery banks. Blue sea two battery switch acr dual charging system.