You have lost the 120v input to the inverter/charger. We know this, because:
- you report that shorepower is not recharging the house batteries
- shorepower is not passing thru (the magnum) internal transfer switch, and
- the inverter IS working, and powering the ouput inverter circuits
- I can send an electrical chart if you need, which depicts how these different functions work in the magnum.
There are a couple things you can do.
First, open the circuit breaker box, and with your voltmeter check that the breaker feeding the inverter has 120v on it. Rare, but you could have a bad breaker. Check also that the connections of both black and white wires are tight.
Next verify at the inverter, that you have 120v at its input. You've already reset the breaker on the magnum itself. If you have power at the magnum, and the control panel has both the inverter and charger turned on, then your magnum is likely defective.
Your risk is the house batteries going dead. With the engine running while driving, they would be getting charged. While sitting however, you'll need to buy a standalone charger. Get at least a 40-50 amp 12v charger, and connect to your house batteries. You can get a smaller amperage if have to since anything is better than nothing, but with the colder temperatures and furnaces running, you're going to need a larger charger. Your magnum probably has a 100 amp charger as part of it, if it were working.
I do want to review your terminology however, just to make sure no misunderstanding.
- when you say half if your breaker box isn't working, you are referring to the sub panel half (those circuits powered by the inverter), correct? You are NOT referring to loosing one of the two phases coming in from your transfer switch, correct? When on shorepower or generator, everything on BOTH 50 amp legs are working, except the inverter/charger and its downstream inverter fed circuits.
DaveB, Raleigh, NC
2015 Tiffin RED 33AA, w/Honda CRV
VMSpc, Magnum BMK/ARC50