First, please forgive the book that follows! I sometimes have a hard time getting concise information out!
A couple seasons ago, I replaced my inverter in my camper trailer for a Victron Energy MultiPlus-II Power Inverter - 12V. All works well with 800 watts of solar on the roof an Epever MPPT solar charge controller and two 12 volt VATRER 180 AH batteries in parallel. All summer long I have had just the inverter on 24X7, AC mains power off, just letting solar run things in the trailer and a few outdoor bug zappers.
Well, we finally got several days of good rain in NE Arizona and dark cloudy days. I checked on the trailer and found the Victron in a “weird” state, not inverting and the simple GX multi-control panel showed 9 or 10 in the digital display, not the 30 I set it too. I switched the multi-display to off and the display still showing this odd number. I cycled the AC power and nothing changed when switching to off, inverter, off charge only etc. When going to the inverter itself and using it’s main power switch, things reset. Turned it back on to inverter so it would charge and have AC power and you could hear the transformer easily after a few seconds. I left thinking all was okay but came back hours later and the system was not charging nor was there AC output. The display showed 30 which is the current I set it at for my 30 amp trailer connection. I had to do this a couple times to get things charging and have a continuous output.
After a day or so, the batteries were fully charged so I turned off the AC Mains and inverter only. With the seasonal sun change and things getting cooler, leaves shading the panels it is time to remove the batteries and put the trailer to sleep for another winter. So… I turned the AC back on. Went into the trailer and watched the panel go from inverter to charge, LEDs switching appropriately. I cold hear the inverter transformer load up again and I did have AC output. After about 20 seconds, I could hear a relay in the inverter click, no AC power, no LED indicator lights but still had my 30 setting in the digital display showing. after about another 20 seconds it switched back on, LED went from inverter to charge - absorption heard the transformer load up again and this cycle repeated itself for about five minutes. Since the batteries weren’t too depleted, (my assumption), this finally stopped and things settled down.
I know this is not normal behavior. I searched and cannot find this problem so I seeking some thoughts on what might be at issue. There are no blinking LEDs or other indication of a fault on the inverter itself or on the control panel inside the trailer.
The area that the inverter is located in seems to have adequate ventilation and area. I know there is a fan in the inverter but now that I am thinking about it I have not heard it come on. But I do hear that transformer load up when it first starts its charge cycle whether the batteries are down a little or a lot.
Thanks so much for any help and thoughts on this and what I might start looking for.
John