Ground Fault on a Fox ESS H1 G2 single-phase hybrid inverter: The ground connection is failed
Short answer
On a Fox ESS inverter, Ground Fault means: The ground connection is failed. The inverter stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 24 September 2026 · 1 source
What it means
The manual says: The ground connection is failed.
Part involved: earth/PE connection.
When it shows: Ground connection check fails.
Likely causes:
- Earth connection failed; N-PE voltage abnormal; AC wiring fault.
Is it safe?
Switch the inverter off at its isolator and call an engineer.
| Does the inverter stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The inverter stops until the fault clears or is reset.
Resetting itself: unknown.
Manual reset: Disconnect PV, grid and battery, then reconnect (installer).
What you can check
- Read the full code and message on the inverter screen or in the FoxCloud app and note the date/time for your installer.
- Check the inverter's AC isolator next to the inverter and the solar/battery breaker in the consumer unit are ON (do not reset a breaker that trips again - call your installer).
What the engineer will check
- Check voltage between N and PE; check AC wiring and earthing arrangement (TN-C-S/TT); Fox manual action: 'Disconnect PV, grid and battery, then reconnect' - this involves DC and battery isolation and is for the installer.
Who to ask for: Qualified electrician / MCS PV installer.
Certification: Work on DC strings and inverter enclosures: competent PV installer (MCS-certified installer for warranty/SEG continuity); electrical work notifiable under Part P (England & Wales) or equivalent.
What you might notice
Sources
- H1(G2)/AC1(G2) Series User Manual ↗ · V1.0.8 · page 48 · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026