IE:00020 on a SolaX Power SolaX X1-Mini G4: IsoFault - Isolation Fault
Short answer
On a SolaX Power inverter, IE:00020 means: IsoFault - Isolation Fault. The inverter stops until the fault clears or is reset.
Reviewed 24 September 2026 · 1 source
What it means
The manual says: IsoFault - Isolation Fault.
Part involved: PV array insulation resistance (Riso).
Likely causes:
- Low PV insulation resistance; connections.
Is it safe?
| Does the inverter stop? | Yes |
|---|---|
| Severity | Fault — clears by itself when the condition goes |
The inverter stops until the fault clears or is reset.
Resetting itself: often - the inverter retests insulation at each start, so a moisture-related fault can clear later in the day as the array dries and return next damp morning.
Manual reset: no (clears when insulation test passes).
What you can check
- Read and note the exact code and time from the inverter display or app (screenshot).
- Note whether it only happens in the morning or after rain - tell the installer.
- Check the solar/battery AC isolator and the consumer-unit breaker/RCD are ON (do not reset a breaker that trips again immediately).
- Do not touch panels, DC cables, connectors or the DC isolator.
- Where the SolaX manual says 'press the ESC key to restart the inverter', a homeowner can do that on the display. Steps that say 'disconnect PV+/PV-/battery' are for the installer only.
What the engineer will check
- Insulation-resistance test each string PV+ and PV- to earth (per IEC 62446-1 / BS 7671 Section 712).
- Inspect MC4 connectors, cable damage (rodents/roof edges), water ingress in DC isolators/junction boxes.
- Check module frame earthing.
- Disconnect strings one at a time to find the faulty string.
Who to ask for: PV installer with insulation tester.
Certification: Electrician competent in grid-connected PV (BS 7671 Section 712; IET Code of Practice for Grid-connected Solar PV), ideally the original MCS-certified PV installer; brand-approved/trained installer to keep manufacturer warranty.
What you might notice
Sources
- X1-MINI G4 User Manual Version 9.0 (Version 09, 30 Jun 2026) ↗ · 9.0 · page PDF p.97 · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026