FoxESS
Grid Lost
Grid Lost
Inverter cannot detect the AC grid. May be a genuine outage or a wiring/CT clamp issue.
Common causes
Grid power outageAC isolator open or tripped MCBLoose AC wiring at inverter terminalsCT clamp not fitted or fitted incorrectly
What to check
STEP 1
Check the AC isolator and consumer unit — confirm grid is present with a voltage tester at the isolator terminals
STEP 2
Check CT clamp is fitted correctly on the correct phase conductor and clamp jaws are fully closed
Escalate if
Grid is confirmed live but fault persists — escalate to Fox ESS UK support
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