2033 on a Huawei SUN2000-L1 single-phase hybrid-ready inverter: Grid voltage below threshold or LVRT duration exceeded (Major)
Short answer
On a Huawei inverter, 2033 means: Grid voltage below threshold or LVRT duration exceeded (Major). The inverter stops until the fault clears or is reset.
Reviewed 24 September 2026 · 1 source
What it means
The manual says: Grid voltage below threshold or LVRT duration exceeded (Major).
Part involved: grid voltage.
Likely causes:
- Grid abnormality.
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: yes.
Manual reset: Recovers automatically when grid normal.
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).
- If it happens occasionally it is a short grid disturbance and clears itself; if frequent (especially sunny afternoons) ask your installer to check local voltage with the DNO.
What the engineer will check
- Check grid voltage; with DNO consent adjust threshold via app/SmartLogger; check AC switch/cable.
Who to ask for: Installer, with DNO (network operator) if grid supply is at fault.
Certification: None for homeowner checks; any grid-protection setting change needs installer and DNO consent (G98/G99).
What you might notice
Sources
- SUN2000-(2KTL-6KTL)-L1 User Manual (Copy, AU) ↗ · Issue 06 · page PDF p.88 · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026