Newbee to community: The MPPT 150/70 installation manual states that I need a GFPD but I am not sure what I need and where it is installed. I'm familiar with 120Vac circuit interrupts but not 12Vdc equipment interrupts. My system consists of three 330 watt solar panels on the trailer roof wired in series and three 100ah AGM VRLA RV deep cycle batteries wired in parallel to a 2000 watt inverter. Any suggestions as to an appropriate device and source would be appreciated. I'm self installing as there is no local solar installer that deals with trailer/12Vdc installations and my distributor is in another state. Thank You in advance for any advice you share.