AIO off grid oddity

Another weird observation with the AIO. (Non-solar installation)
This happens when OFF GRID only. (Either by portal remote control or physical isolators in meter cupboard)
The ring main RCBO trips even though ALL items are unplugged, Testing with a socket tester (BUZZIT) shows "NO EARTH >50k ohms" ) Once GRID is reconnected the problem goes away and all tests are good.
I've checked all the earth wires, "stake" to meter cupboard busbar and from there to AIO and Gateway. All look good so the fault must be somewhere in the Gateway or AIO/inverter?
Obviously this is only a problem IF the grid is isolated from the house but still a concern-- would be interested if any other AIO customers have observed this behaviour?

Warekiwi I think the AIO does weird things on Neutral Earth bonding that may be screwing with the tester.
What voltage do you get between Neutral & Earth?

I have had this very same issue. After hours and hours of my installer on the phone to GE, GE decided that it is "something in the house".
Interesting, the you disconnect the RCBO's functional earth cable, they do not trip. This clearly indicates the problem is with the Gateway.

hoggy I'm reluctant to go OFF GRID right now as there has been so many problems with the unit in the past 12 hrs. (Mostly trying to reconnect GRID after disconnecting in the effort to get AIO to supply house outside of cheap times) It's not just the socket tester though- the main ring main RCBO trips whenever the grid is disconnected and this NEVER happens normally (using either battery to load or grid to load)

It's imbalance / leakage causing it to trip.
Without getting too technical you (or your installer, I'm not sure who I'm talking to) may find that you have voltage between Neutral & Earth when in Off Grid Mode and it's this which appears like leakage to your RCBO and tripping it.

Shouldn't the in house neutral be bonded to the earth stake when off grid. Otherwise the inverter would be floating and you would get an arbitrary voltage between neutral and earth,

nophead the AIO/gateway is supposed to do it, but I've seen that some people on here get 120V N-E when off grid. Not having one I don't know if this is intentional but it does cause issues (I believe Growatt inverters go into fault because of this and need settings changed to ignore the >30V N-E alarm)

Did you sort this?
Just curious why some people get these trips and others don't. (If it really does run 120V N-E as some report, then I do wonder if it equally runs 120V L-E but 180' out of phase. Basically like America. I really cant think of a reason why it'd do it otherwise but that would upset RCDs.
Not something you'd really think to check over here normally though.

hoggy This is exactly what my AIO is doing and my Growatt inverter throws a fault immediately when the grid fails.

NC what fault does the growatt say? Something along the lines of Neutral Earth alarm?

hoggy I don't think it says anything actually. it just turns the little leaf red and flashes. It's the inverter with the tiny little screen. Tomorrow I can manually trip it and have a closer look and see if there's an error code. My installer says I need a firmware update to resolve this. A quick google tells me that's a complete PITA to do.