Inverter Open Ground

[12VoltInstalls]

4ga is insufficient for your expected load.

1/0 is barely there imho- vastly larger than 4.

It’s shutting down because the surge sags the input and the inverter interprets either ‘overload’ or low battery. I use 2/0 for my 1200W pure sine. I’ve never overloaded on purpose but other than a few times with some 20-year-old junk batteries it’s never shut down. I’ve had new batteries for 2+ years without a single shutdown.

that’s my take on it

 

[Aquanuts]

If your microwave is drawing 10amps, that's about 1400w draw including inefficiencies. Surge could be 4200w to 5600w at startup. If other stuff runs fine from the inverter then id say it's underpowered. Is it pure sine? What size are your cables to the inverter from battery and how long?

I spoke with AIMS tech support. The problem is that the inverter is under powered for the surge of a microwave, at the size is about 3kW. Their recommendation is a 3kW/6kW for a microwave That may be a little high as I have read others say at least 2kW/4kW. Bigger can't hurt but it costs more. The issue of the open ground reading is because the neutral line is carrying voltage and must float from the ground. I asked if tying neutral to ground would damage the inverter and without hesitation the answer was yes. This information can be added to the bank of knowledge that is on this blog.

Thanks to everyone who chimed in. You helped me discover the solution, buy a larger inverter or only run the microwave on the generator.

 

[12VoltInstalls]

…and use bigger supply cables. Did you try that?