I'm having a strange issue with an onboard Onan 5500 LP generator and a Multiplus II 2X120 in a 5th wheel. This is a brand new installation with all new equipment. The Multiplus works as expected with shore power and when inverting. When I disconnect from shore power and start the generator, the Multiplus passes the power through for a short duration, then the internal transfer switch opens up and it goes back to inverting (this is when the Multi is in the ON position). The pass through power stays off for a short duration and then the transfer switch closes and it starts passing the generator power through again. This process just perpetually repeats itself.
When I put the inverter in Charger Only mode via the physical switch on the inverter, it passes the generator power through with no issues.
I did some measuring of the power coming from the generator and see the generator output is in the 63 HZ range. I thought maybe this was causing the issue, but when I checked the Multiplus settings, the Accept Wide Range of Power (45-65 HZ) was checked. The only other setting I thought might be causing an issue was the UPS Function setting. I turned this setting off in the Multiplus, but haven't gone back to the rig to test the generator with the setting change (it got too late and cold/wet to be outside). I will run some more tests in the morning with the setting change.
I thought I would run this by the group to see if anyone had experienced something similar and had any other suggestions.
