Overtemperature Huawei — Thermal Derating
At a glance
- Severity
- WARNING
- Domain
- INVERTER_FV
- Reference standard
- IEC 62109-1 / IEC 62109-2
- Product / context
- Internal overtemperature
What it means
The inverter reduces its output power (thermal derating) to protect internal components from overheating. Production drops significantly during midday hours, especially in summer.
Probable causes
- Ambient temperature above 45 degrees C in the room or cabinet housing the inverter.
- Internal cooling fans faulty or blocked by dust and debris.
- Clogged air filters (on inverters with forced filtered ventilation).
- Inverter directly exposed to solar radiation without adequate shielding.
- Insufficient ventilation space: minimum clearances between inverters or from the wall not met.
Where to start
Measure the ambient temperature in the room/cabinet where the inverter is installed using a calibrated thermometer. Is the temperature above 45 degrees C?
Full guided diagnosis in the app
The diagnostic tree for this fault has 7 guided steps with measurements, checks and resolutions. You'll find it in ElectraIQ, one of the five IndexOS apps: free, works offline.
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The same fault on other brands
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