The twist here is that the error ONLY happens when the grid is OFF, during the 2-4 hours of load shedding.
Syncing to the grid works perfectly every time. Never a problem when the grid is on.
Equipment:
MPII 5kva, installed for a long time, never a problem.
Latest firmware on the inverter, MPPT's and the Cerbo.
Carlo Gavazzi, so not using AC_Out1.
Grid-tied.
Tests done:
Manually testing syncing syncs perfectly with the grid.
Also disconnecting the inverter, L&N from the DB during load-shedding, the error still appears.
Checked all loads.
No DB tripping either.
Inverter output during load-shedding event:
Live /Neutral = 231v
Neutral /Earth = 0v
Live /Earth = 231v
I repeat, never a problem when the grid is on, or when it syncs with the grid, just when the grid is off due to load-shedding, that the error randomly appears
See 2022-09-19 at 2:14 am, not a problem during that load shedding event.
The one starting on 2022-09-189 at 10:16 am, had the most errors ever.
Still getting errors, just not as frequent, since I am switching off the L&N between AC_In and DB.
The actual Error:
The volts on AC-Out1 drop for no reason, eliminated loads already. Just happens suddenly, and ONLY when the grid is off.
Batteries are normally charged, volts are perfect, BMS has no errors or warnings, checked all the battery connections.
Is this a unit problem/relay?
Does anyone have any more suggestions I can check, please?
This is not a normal error, no-one seems to have reported this ever that I could find.
To take the inverter in, during the current load-shedding woes, which will take weeks to check/repair assuming there is a fault, would be a complete disaster. Am also told it would be a repair, not a swap.