2001 on a Huawei SUN2000-L1 single-phase hybrid-ready inverter: PV string open-circuit voltage exceeds max operating voltage (Major)
Short answer
On a Huawei inverter, 2001 means: PV string open-circuit voltage exceeds max operating voltage (Major). 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: PV string open-circuit voltage exceeds max operating voltage (Major).
Part involved: PV input.
Likely causes:
- Too many PV modules in series. Cause ID 1=PV1, 2=PV2.
Is it safe?
| Does the inverter stop? | Yes |
|---|---|
| Severity | Fault — needs a manual reset once the cause is fixed |
| Engineer needed? | Yes |
The inverter stops until the fault clears or is reset.
Resetting itself: no.
Manual reset: Alarm disappears after PV array configuration is corrected.
What you can check
- Read the full code and message on the inverter screen or in the FusionSolar 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 string series configuration vs max voltage.
Who to ask for: MCS-certified solar PV installer (DC/string work) or the original 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
- SUN2000-(2KTL-6KTL)-L1 User Manual (Copy, AU) ↗ · Issue 06 · page PDF p.87 (printed 79-80) · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026