I am building an off grid Solar system based on the MPP LV6548 all-in-one inverter as inspired by William Prowse you tubes. I have purchased 20 Renology AGM batteries 12V 100AH batteries and have ordered my MPP LV6548. Initially I plan on using 2 strings of pv panels totaling 4000 Watts. I am on the grid but want a parallel system to knock down my bills. In my next post I will put up my wiring diagram. Cheers