We have "Tiny peakshaver" as short term solution for grid quality improvement at the end of long low voltage overhead line. Setup is three Multiplus 12/1200/50-16 (in three phase configuration) with 330Ah AGM Deep cycle battery pack. Feeding from DC to grid is not allowed, so grid code is default "None". After two day running suddenly L3 phase starts back feeding. It stopped after turned of and on inverters. After 30 min it started again, then after "System reset" via Remote console everything is back to normal.
Power Assist and Dynamic current limiter is enabled. What could cause backfeed? Currently backfeed is not confirmed by utility electricity meter.
