The reason for the subpanel is to isolate those items that will be fed from the inverter. You don't want two sources feeding the main panel, i.e. shorepower and battery power that has been inverted to 120 volts AC. Therefore, you have to install a subpanel to take power from the inverter to specific circuits. Now IF you had a pair of 6500 watt inverters (and a gigantic battery bank) you could in theory run the entire coach off of the inverters. Otherwise the subpanel isolates those circuits you want to power from the batteries. The newer inverters have a built in transfer switch to allow them to use shorepower (the AC in posts on the inverter) when it is available to feed the subpanel. When you remove shorepower, the transfer switch in the inverter instantly changes over to the batteries and converts the 12 volts DC to 120 volt AC to continue feeding the circuit in the subpanel through the AC out posts on the inverter).
With a 4.8K inverter you are going to need a LOT of batteries if you attempt to sustain anywhere near that load. I have a pair of 8D AGM house batteries and if I don't turn my separate icemaker off, I can bring those batteries down in 4-6 hours to the point that I need to start the generator. Newell originally wired my coach such that the icemaker would run off the inverter ONLY when the engine was running to constantly recharge the batteries. I did not wire it that way when I installed the new inverter/charger.
Oh, you didn't ask but I would leave the original battery boiler in place if you have the room. The new inverter/chargers do a better job of controlling the recharge of the batteries BUT if the batteries really get badly discharged, they will not bring them back to life the way the old single stage chargers will. Just unplug the old charger from the AC outlet and it will be disabled until someday when you need it.
|