I'm no expert, but I can offer a couple of tips:
- The solar charge controller needs to be isolated from the feeds to the Inverter and Trailer, or else the power from the solar will not charge the batteries when the system has any draw.
- The batteries need to be isolated to prevent them from simply discharging each other Carliving.info - Free information about living in cars, vans and campervans.
- The Trailer and Inverter need to be connected at the same point in the chain, and also isolated to prevent them from competing for the current - a distribution panel is the best option there.
- Check to ensure that all of the batteries are deep cycle. If you mix deep cycle and non deep-cycle then you will wear out the batteries much faster, and will only get 20% of the rated time as the non deep-cycle batteries will give out of power and break the circuit, becoming resistors.
Reference http://analoglogic.net/projects/solar_charger/solar_charger_system_diagram.png- treat the battery band as a single unit battery once you have each battery connected in parallel and isolated.
