@guystewart Was the issues solved?
Even I am from Belgium, I may have same problem as on this topic.
My network is 3x230, no neutral. Only PE. Voltage PE to any phase ~115, Voltage between phases 230V.
I intend to use single Multiplus-II GX. Would it work? Will the ESS function be available?
The AC2 will not be used / connected, unless city black-out and I will need to manually disconnect from city. (Sounds strange, but I will not change house network. Not allowed.) Then connect AC2 for lights only.
So far, on forum in my area are only questions. No clear answer. @alexpescaru Looks like you are from Europe. Have you encountered this situation / setup?
I call here for help, as I am stuck for some time with solutions.