How do I fix AC Frequency Out of Range on a Growatt?

Check frequency reading in ShinePhone. Log over time to determine if it is transient or persistent Then: If persistent, check G99 frequency response settings in inverter

Growatt

Error 304

AC Frequency Out of Range

Grid frequency is outside the permitted window (47–52 Hz). Inverter disconnects.

Common causes

Grid instabilityLocal generation imbalance on weak grid

What to check

STEP 1

Check frequency reading in ShinePhone. Log over time to determine if it is transient or persistent

STEP 2

If persistent, check G99 frequency response settings in inverter

Escalate if

Frequency persistently out of range — notify DNO

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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