Huawei · PV inverters · Huawei SUN2000-KTL-M1 (three-phase inverter, 3–10 kW, battery-ready)
Alarm 2037Grid underfrequency
Name in the manufacturer's documentation (fault list): Grid underfrequency
[1]
In plain words (editorial)
The grid frequency is lower than the local standard allows; the inverter shuts down. If it happens only occasionally, the grid was temporarily abnormal and the inverter recovers automatically once the grid is normal again.
When to call a service technician: If it happens frequently, contact your installer – the grid values may need to be checked with the local power operator; protection thresholds may only be changed with the operator's consent.
✎ editorial – written from the cited sources, not a manufacturer statement. Status: draft.
For technicians
Possible causes (source text)
- Power grid exception: the power grid frequency is lower than the frequency required in the local standard.[2]
Steps given by the manufacturer (source text)
- If the alarm occurs occasionally, the power grid may be abnormal temporarily. the device automatically recovers after detecting that the power grid becomes normal.[3]
- If the alarm occurs frequently, check whether the power grid frequency is within the allowed range. if not, contact the local power operator. if yes, modify the power grid underfrequency protection threshold after obtaining the consent of the local power operator.[4]
What the device does (source text)
- The device is shut down.[5]
⚠ Work on refrigerant circuits, mains electricity and PV DC wiring is for qualified technicians only.
The Polish page has more detail (plain-language explanation, safe checks, guides): Read in Polish →
Sources
Every statement has a footnote to the document and PDF page. “Quote verified” means the quote was found automatically in the text of that page.
- [1] Inverter Alarm Reference (Issue 14, 2026-06-15) (EDOC1100345192 Issue 14) , p. 44 official manufacturer document quote verified
2037 Grid underfrequency
- [2] Inverter Alarm Reference (Issue 14, 2026-06-15) (EDOC1100345192 Issue 14) , p. 44 official manufacturer document quote verified
power grid exception: the power grid frequency is lower than the frequency required in the local standard.
- [3] Inverter Alarm Reference (Issue 14, 2026-06-15) (EDOC1100345192 Issue 14) , p. 43 official manufacturer document quote verified
if the alarm occurs occasionally, the power grid may be abnormal temporarily. the device automatically recovers after detecting that the power grid becomes normal.
- [4] Inverter Alarm Reference (Issue 14, 2026-06-15) (EDOC1100345192 Issue 14) , p. 44 official manufacturer document quote verified
if the alarm occurs frequently, check whether the power grid frequency is within the allowed range. if not, contact the local power operator. if yes, modify the power grid underfrequency protection threshold after obtain…
- [5] Inverter Alarm Reference (Issue 14, 2026-06-15) (EDOC1100345192 Issue 14) , p. 43 official manufacturer document quote verified
the device is shut down.