@FireWizard.

Thanks a lot for explaning.
I was "missing" the energy read "computed" setting.
I adjusted it and now it works fine!

Thank you for the node-red flow.

I have one question: How do you get the kWh per inverter in domoticz?
I have found another dzVents script, which uses the (once per) 15 minutes value and adds the Watts divided by 4 to get the Wh.
As I am not a software engineer ;-) , do you have that working in ...