2 multiplus Ii inverters 12vdc 3000W and 2 separate battery banks.
When shore power is disconnected inverter b produces 120vac
Inverter A produces 160vac. These voltages are measured at the multiplus output.
When on shore power both have 137vac at outputs ands inputs because of pass thru. Both are being fed shore power from 137vac service. (Mexico, seldom serves up 120vac)
Both inverters claim to be producing 120vac according to their cerbo gx setup
Connect to the inverter with a Mk3 USB and VE configure. Check to see that the Inverter AC voltage is correctly set.
Also check to see if the AC wiring is secure - no lose connections or burnt terminals / fuses.
Measure the AC voltage on the inverter output terminals.
Voltage was measured at the output terminals.
I’ll check with config but the cerbo display says 120vac
Have not seen any bad/burned connections and have been over them pretty closely today.
This is new behavior. It was not doing this 1 month ago
As expected the unit was configured at 120VAC for the output, just like the Cerbo showed. The voltage has now edged up to 180vac and I´ve disconnected it from the house wiring so all the measurements are being taken at the unit
Also the unit will not go into ¨charge only¨ so I had to rewire the boat to join the battery banks and remove A from the system. So now the Second inverter is powering the entire boat but that should be fine for the moment since the loads are never that high (well under 3000W) while we solve this problem. Everything in the boat is working just fine on Inverter B so it appears to just be Inverter A that has lost its ability to regulate its output.
This overvoltage issue only happens while inverting, not during pass thru and happens even if the boat is not connected to shore power at all.
The voltages between the 3 wires add up sort of as expected
180Vac L-N
120Vac L- Frame
60Vac N- Frame
I’m contacting the dealer to see about an RMA but if there is anything anyone can suggest, I think this one is going down as a defective unit.