System was required and designed to be a hybrid operation, with grid connection. System installed 24th March and operates fine with grid connected until the Battery SOC reaches 95%. Then the Victron shuts down the Fronius and when it restarts the Victron output voltage constantly fluctuates between 226V and 258V at about 60 voltage spikes per minute. Victron unit was replaced in late July by supplier as suspected it was faulty, no change, issue still there. Have the grid switched off to reduce risk of damage to sites motors. Two different Victron dealer and their experts have not been able to provide a solution and have given up. Our location is rural and have seasonal times with low solar input, so grid was essential for these times plus we have lost the ability to export to the grid.
System comprises 7.5kw panels, Fronius Gen24 including Smart Meter, 20kw Pylontech batteries and due to issue with Victron anti islanding function had to install a ComAp MainsPro and isolating contactor. Any input to this issue would be appreciated.