Hi Heimo1
Please find below an alternative procedure that will help you implement the no-load functionality using ADE7880 in a uniform way, even if the phases are entering no-load condition one-by-one.
I have not checked this in the lab yet. I will definitely check the flow and let you know if it works as expected, once I get a chance. If you get a chance to check this on your setup or if you have any concerns with the above procedure, kindly let me know.
Regards
hmani