The inverter detected a condition suggesting it may be islanding (grid disconnected but inverter still running) and disconnected for safety.
Common causes
Momentary grid dropout or brownoutLoose connection on main supply incomerConsumer unit MCB on grid supply briefly tripped
What to check
STEP 1
Check mains supply at the consumer unit. Confirm grid is present and MCB has not tripped. Inverter should auto-reconnect within the G98 reconnection delay (typically 20s)
STEP 2
If anti-islanding trips repeatedly, check for loose connections on the main supply incomer and consumer unit input terminals
Escalate if
Anti-islanding tripping multiple times per day with confirmed grid present -- potential inverter relay fault, escalate
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