I bought 4 used 250W solar panels from San Tan Solar in Arizona. I want to put them on my RV. I initially purchased a 40A EPEVERS MPPT charge controller, but I've been seeing videos where it says that it can only handle 520W of power. What size MPPT controller do I need to buy? Also, how do I determine the correct gauge of wiring to use from the battery to the controller and the inverter ?