I’m considering a G98 install with Multiplus 2 connected to the main consumer unit solely via the bidirectional AC-IN port, so that it’s augmenting the general daytime load.
The main regular daytime load over 3kw is water heating, so in theory, I could share the battery (15kwh lifepo4) with a non-charging inverter that effectively provides off-grid power to a single water heater load. The battery itself should easily support the total current.
I should be able to use the relay out to shut off the dumb inverter when the battery is below some level.
Since the power from the second inverter can’t export to the grid, I should be able to stay within G98.
The question is really whether the Multiplus will freak out if it sees the battery reporting a bigger power draw than the MP is drawing itself, and whether it will affect charging.