I currently have a lithium (LiFeP04) battery bank, that is below freezing (10F/-12C) so I can't charge it in a camper van. I'd like to connect the shore power, which goes via a breaker to the Quattro. I'd like to keep the batteries disconnected (via BlueSea switch that usually is used to cut power to the Quattro, not the other way around) while I run an electric heater from the grid power while it is hooked via the external port (i.e. not leave a door to the van open while heating). My solar will also be disabled until the batteries are up to temp.
I see the manual has recommended battery sizes, but has anyone tried this passthrough mode approach? Many answers linked above talk about low voltage alarms/ripple warnings, some say it'll work, some recommend against.
I would be doing this for hopefully < 5 hours (but perhaps from time to time if the weather is cold and the van is unused), and simply to avoid adding a dedicated outlet powered by the the shore power circuit.