I am purchsing components for a solar system. I was originally thinking about the 400 watt 12 v set up but, have since switched to the 24V set up. I have 2-180 watt poly Bougerv solar panels. the Bougerv solar panel specs are: 180 t/-5%, open circut voc 21.6 t/- 5%, max power current IMP (a)...