How do I fix Grid Undervoltage (Alarm 1011) on a Solis?

Check the grid is present and the main breaker is on. Then: Measure voltage at the inverter AC terminals and at the consumer unit, compare the two.

Solis

UN-G-V

Grid Undervoltage (Alarm 1011)

Grid voltage below the standard limit. Variants UN-G-V01 and UN-G-V02 (transient).

Common causes

Supply faultLoose AC connectionVoltage drop under load on a long AC run

What to check

STEP 1

Check the grid is present and the main breaker is on.

STEP 2

Measure voltage at the inverter AC terminals and at the consumer unit, compare the two.

Escalate if

Voltage normal but alarm persists

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