I have 2 Orient Power 48V 100Ah 5.12Kwh Powerwall LiFePO4 Wall Mounted Battery connected in parallel to 2 Orient Power LV6548 120VAC 48V 6500W inverters connected as US split phase. I don't have AC grid in connected. I am only pulling like 200 Watts at the most on the AC output side mostly from inverter 2.
Every so often one of the inverters goes into failure and shuts down both my inverters. Sometimes the system restarts after a bit automatically, but others I have to manually turn everything off and on again. Both batteries show OVP, UVP and SCP errors.
Check the communication wires betwee 2 inverters, set the other battery as master battery to connect to inverter communication.
Or on both inverter, the battery mode set as AGM.