Multiplus ii is setup in ups mode with 5kw generator on AC1. With generator running, the inverter shuts down when a 15a motor starts. This happens with and without power assist. This motor easily starts and runs and does not overload the generator when connected directly to the generator. Why is the multiplus even trying to take the load? Why is it overloading the inverter if the load is well under the generator's capacity (inverter should not even be interfering)?