Have almost year installed Multiplus II 48/5000 GX (230V) in serial connection between grid and small house. From unknown reason I've found non-zero AC voltage between PE and N (90V~110V based on load). The PE - N voltage before Multiplus is 0V. There's non-zero PE-N voltage on AC OUT1 even I disconnect all harness from the output.
I'm using virtual switch, grid without code to avoid feeding back to the grid. The inverter/ground relay checkbox used to be unchecked in settings. On the AC IN there's 3 wire TN-S grid as well as on the output there're 3 decoupled wires. Batteries/Multiplus/house GNDs are all well interconnected with PE.
Regarding to I'm 100% sure TN-S 3 wire cable goes directly from place of decoupling TN-C to TN-S I've temp. resolved situation by activation of grounding relay (voltage PE-N felt back to 0V)... but in my country that's against valid code.
Is it case for warranty or is there anything what I can try?