New Solar Install

Lwiddis wrote:
What wire size from each panel to combiner box? From box to controller? From controller to batteries. 12 volt? 24 volt? To the controller.

Usage determines watts and with configuration, distance, etc wire size can be determined with a wire calculator.

All RVs use 12V batteries except a few that have converted to 24V house batteries.

$/W is more expensive for 12V panels, 24V 60 cell panels are a good cost size tradeoff. 72 cell panels are rather long for a RV roof but may fit.

There are a lot of variables that need to be determined before wire size and power loss can be optimized.

My 3 serial panels have 62' of 10ga wire to the controller for a wiring loss of 0.6%, no combiner. The wires to the 12V battery are sized for 52A.