That really looks like a faulty current sensor in the Multi … I’d be out of it then … how old is the Multi … maybe a warranty on the device ?
An external current sensor would be a solution …
If you are only single-phase, an ET112 would work in front of it
Hi Steffen
Its 1 years old thank you for your help.
Oh these damned holidays 
Do all the “big” loads really have to be behind the multi ?
With an external metre, you could also leave the large loads in front of the Multi. The ESS would still work.
If your main fuse was blown, your devices wouldn’t work now and/or your battery would have run out long ago.
Can your main fuse even let 100A through?
No my main fuse is 80amps
Then you should definitely reduce your input current limit to at least 80A via. Ve Configure but for VE Configure you need the MK3
If you are using devices and your battery is still charging, you can also exceed the 80A.