Growatt
Error 302
No AC Connection
Inverter cannot detect the AC supply. Grid appears absent.
Common causes
AC isolator open or MCB trippedLoose AC wiring at inverterPhase missing on 3-phase systems
What to check
STEP 1
Check AC isolator and consumer unit MCB. Confirm grid present with voltage tester at isolator terminals
STEP 2
Check L, N, PE terminal connections at inverter are tight. On 3-phase, check all three phases are present
Escalate if
Grid confirmed present and wiring confirmed correct — possible AC detection hardware fault, escalate
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