Just to add my two cents.
Yes, when plugged into shore power, you will still use 12v power as well (all the 12v items). But if you are on shore power, your charger should cycle on to recharge batteries! If your batteries are running down overnight, while plugged into shore power there is something wrong with your charger circuit.
If you are on battery power only, keep in mind that inverters are not very efficient. You may only need 100 amps of power, but the inverter may use 125 amps to create it. And normally, an electric space heater hooked to an inverter, will draw batteries down very quickly.
You need to check your wiring design to find out what outlets are actually powered by the inverter. Usually it is only the TV's and an outlet or two. Most refers that run on propane are not wired to be on the inverter circuit, if the 120v cuts off, it just auto switches to propane.
Remember the difference between watts, amps, 120v, and 12v. A toaster or space heater might use 1500w, where as a LCD TV might only draw 50w, all on a 15amp fuse. To create 1000w with 120v you need 8.33 amps, but at 12v (assuming 100% inverter efficiency, which it isn't) you will need 83.33 amps. Now remember that battery you just got, with its 220 amp-hour rating, those 1000w put quite a draw on it on a cold winter night.
I had one of my 12v batteries go bad after a year, so I replaced both with CostCo 6v Golf Cart batteries. So far, so good, casino camping in cold weather, propane furnace running, watch a little tv, etc., had no hesitation when starting the generator the next morning.
__________________
2010 Journey 39n - 2017 Jeep Cherokee Trailhawk - this our 13th year living aboard, travelling and visiting the Pacific NW, summer 2023
|