F153 fault in WEG CFW900 Drive indicates a Power Internal Air Overtemperature. This means the ambient air inside the drive exceeded critical limits, triggering a protective shutdown.
Cause:
Internal air overtemperature fault.
- High ambient temperature around the inverter (>50 °C) and high output current.
- Defective internal cooling fan (when applicable).
Remedy:
Check local cooling conditions, clear air blockages, and ensure cabinet fans are running correctly.
