Howdy.
My system is an off-grid solar solution, there is no grid and never will be. When I first set it up, I was unable to source a Multiplus, so I bought a 5K 120v quattro instead. It feeds a single 100amp autotransformer which I'm using as a step up to provide split phase 220v service. I'm looking at adding another inverter to support additional power draw. I believe, but would appreciate confirmation, that I can add a 5k 120 Multiplus to the system, instead of purchasing another Quattro. Would the best solution be to rewire the autotransformer from a step up configuration to passing through the two 120V legs from the two inverters?