MultiPlus 12/800/35-16 with firmware v476, having problems with the MultiPlus UPS function not working sometimes. If I activate the circuit breaker leading into the multiplus, the UPS function kicks in every time. If I get a power failure from the mains, the UPS function works, probably only about 20% of the time.
When the UPS fails to work, If I cut all 12v power with circuit breaker, it seems to reset the MultiPlus and then its starts "ïnverting"
This is a new development, and has worked flawlessly for about 6 months.
Any body have any suggestions.