F0068 fault in WEG CFW500 Drive indicates Motor Overtemperature on a dedicated input. This means the motor’s PTC thermistor detected excessive heat, triggering a hardware-level thermal protection trip.
Cause:
- Overload on the motor shaft.
- High start/stop duty cycle.
- High ambient temperature around the motor.
- Loose contact or short circuit (3 k9 < RPTC < 0 k1).
- Motor thermistor is not installed.
- Motor shaft is stuck.
Remedy:
Check the motor shaft and driven load for mechanical blockages. Optimize duty cycles. Measure thermistor circuit resistances and secure connections.