First and foremost, sorry if this question comes off as noob because I am. I have a sprinter van that has a Multiplus II 12/3000 inverter/charger and it's main power source currently is a Battle Born GC3. When I run the A/C for example (on 110v) the Multiplus alarms at ~11.8v and shuts off inverting. I have Goal Zero 3000 that I'd like to help feed 110v as a backup to the GC3 if it depletes. Is there a simple solution for this scenario?