Intelligent mode switching over and tripping circuit breaker

[Wescottpower]

Hello all, new to the forum here but have been hovering for a while. Just got my system completely up and running two weeks ago when my solar panels arrived. Had inverter, battery system, and sub panel in place and was using the inverter as a UPS since about this time last year. Now that the solar portion of the system is up and operating, I've been going through some growing pains getting the inverter setting correct with the help of Sungold Power tech support.

Here's my issue, when the inverter switches back and forth between AC (line) and DC, my bedroom circuit breaker in my subpanel trips every time the switch over happens. We have a portable (115v floor standing) A/C unit in there that runs pretty much all the time. When the switch over happens, it sounds like the compressor on the A/C unit stalls for about 5 seconds and the breaker trips. This is the only circuit I have issues with, the refrigerator and the 220v wall unit A/C handle the switch over without a hiccup.

My inverter is a Sungold power LFPV12k split-phase hybrid, the UL1741 model. My Line power has been fluctuating between 233-240v depending on the heat lately so I have put the inverter setting for AC at 230v, the input voltage range setting at "wide", and the frequency setting at "AF" (adaptive to main hertz). I have replaced the 15amp breaker in my sub panel, it was getting weak from my wife running the vacuum at the same time as the A/C unit. Thats a battle I don't want to pick to say the least.

My wife just messaged me and said it happened again but the A/C unit is off. Could it be the ground fault plug on the air conditioner? Could it be the voltage different between the Inverter and utility line in? Has anyone had an issue like this? All of the sub panel circuit neutrals return to the subpanel and not the main breaker panel.

Thanks,
Chris

 

[Mattb4]

Do you have a 3 prong tester? If so do a check of the bedroom outlet that you have the A/C plugged into. If possible both running as inverter powered and also when running off utility. It is possible you have a wiring problem. I doubt it is the ground fault on the portable AC since that would trip and not the outlet breaker. One question though. Is the bedroom outlet breaker a GFCI?

 

[Wescottpower]

It is not a GFCI breaker and I do not have a three-prong tester. As soon as I reset the breaker, everything is fine until the switchover happens again.

I had the wife unplug the A/C after I posted this and it hasn't tripped since so clearly the A/C unit is the issue. Time for a new one, thanks for the reply though, appreciate the help!

This is also showing me I need a bigger battery bank and/or more panels since the changeover is happening more often on overcast days for my load.

Thanks again for the reply!
Chris