Growatt
Error 300
AC Voltage Out of Range
Grid voltage is outside the G98/G99 permitted window (typically 207–253 V). Inverter disconnects until voltage recovers.
Common causes
High grid voltage from export (voltage rise)Weak grid / long cable run causing low voltageLoose AC terminal connection
What to check
STEP 1
Measure AC voltage at inverter terminals. Check ShinePhone for voltage history. Compare to G98 limits
STEP 2
If voltage is high due to export, enable Active Power Management in ShinePhone and set export limit. Check AC wiring is tight
Escalate if
Voltage persistently out of range with no obvious cause — notify DNO
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