How do I fix Internal Hardware Fault on a Growatt?

Perform a full power cycle: DC off, AC off, wait 3 minutes, AC on, DC on. Allow inverter to restart and run self-test Then: Check inverter ambient temperature and ventilation. Confirm input voltages are within spec before restart

Growatt

Error 400

Internal Hardware Fault

A general internal hardware diagnostic failure has been detected. Inverter has shut down as a safety measure.

Common causes

Transient voltage spike or power surgeExcessive heat causing component stressHardware component failure

What to check

STEP 1

Perform a full power cycle: DC off, AC off, wait 3 minutes, AC on, DC on. Allow inverter to restart and run self-test

STEP 2

Check inverter ambient temperature and ventilation. Confirm input voltages are within spec before restart

Escalate if

Returns after power cycle or appears repeatedly within a short period -- escalate with serial number and event log

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More Growatt fault codes

Error 200

AFCI — Arc Fault Detected

PV Isolation Low (RISO)

Error 300

AC Voltage Out of Range