How do I fix Grid Under-Voltage on a Solis?

Measure grid voltage at AC terminals. Check AC connections are tight and correctly torqued Then: Check MCB in consumer unit hasn't partially tripped. Check RCD upstream is fully ON

Solis

E002

Grid Under-Voltage

Grid voltage has dropped below lower limit. Inverter disconnects until voltage recovers.

Common causes

DNO supply issueLoose or high-resistance AC connectionGrid fault upstream

What to check

STEP 1

Measure grid voltage at AC terminals. Check AC connections are tight and correctly torqued

STEP 2

Check MCB in consumer unit hasn't partially tripped. Check RCD upstream is fully ON

Escalate if

Grid voltage within spec at meter but still low at inverter — suspect high-resistance joint in AC wiring

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