Two Multiplus 12/2000 with same firmware and wired as split phase. Inverter 1 (master) is on phase 3, Inverter 2 (slave) is on phase 1. Phase 2 is not being used due to poor power factor. On occasion, after grid power is restored, they will not return to charger mode. I have unchecked "switched as group", and the Phase 2 is set a floating with return to normal. I am using one 12V Relion 100Ahr LiFePO4 battery. Some times the system works normally, other times the Mulit's will not return to charger mode.
On another note, I can only get the system working using the Split Phase 240 setting.