BE09 on a SolaX Power SolaX X1-Hybrid G4: CellImblance - battery unbalanced fault
Short answer
On a SolaX Power battery, BE09 means: CellImblance - battery unbalanced fault. The battery keeps running with some functions stopped. An engineer is needed to fix the cause.
Reviewed 24 September 2026 · 1 source
What it means
The manual says: CellImblance - battery unbalanced fault.
Part involved: Battery BMS internal protection/fault.
Likely causes:
- Battery BMS-reported condition; manual says contact SolaX (via installer).
Is it safe?
Switch the battery off at its isolator if the code comes back.
| Does the battery stop? | Partly |
|---|---|
| Severity | Fault — needs a manual reset once the cause is fixed |
| Engineer needed? | Yes |
The battery keeps running with some functions stopped.
Resetting itself: protection states may clear when conditions normalise; hardware faults do not.
Manual reset: installer/manufacturer.
What you can check
- Read and note the exact code and time from the inverter display or app (screenshot).
- Do not open the battery. If it is hot, swollen, smoking or smells, keep away, switch off at the AC isolator if safe and call the installer (and 999 if fire).
- 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
- Read BMS logs.
- Check cell voltages/temperatures.
- Update BMS firmware if the manual says so.
- Arrange RMA via installer.
Who to ask for: Battery installer.
Certification: Electrician competent in electrical energy storage (BS 7671 Chapter 57; IET Code of Practice for Electrical Energy Storage Systems), ideally the MCS battery installer (MIS 3012); brand-approved installer to keep warranty.
What you might notice
Sources
- X1-Hybrid-G4 3.0/3.7/5.0/6.0/7.5 kW User Manual Version 3.0 (Version 03, 2024-08-08), doc 320101081103 ↗ · 3.0 · page PDF p.126 · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026