How do I fix Relay Fault on a Growatt?

Power cycle inverter. Listen for relay click during startup sequence Then: Check if fault is consistent or intermittent

Growatt

Error 405

Relay Fault

Internal AC or EPS relay has failed to operate correctly.

Common causes

Relay mechanical failureControl signal faultWelded relay contacts

What to check

STEP 1

Power cycle inverter. Listen for relay click during startup sequence

STEP 2

Check if fault is consistent or intermittent

Escalate if

Relay fault persists — hardware fault, escalate to Growatt UK support

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