PTC Motor Temperature Fault

What does PTC mean?

This fault is triggered when the PTC (Positive Temperature Coefficient) thermistor embedded in the motor windings detects an over-temperature condition. PTC thermistors provide rapid thermal protection due to their steep resistance change above a nominal temperature. This indicates the motor's temperature has reached a critical threshold. Ignoring this fault can lead to rapid motor insulation degradation and ultimate motor failure.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Inspect the motor's cooling fan and fins for obstructions or malfunction, ensuring effective heat dissipation.

2. 4

   Check for mechanical overload on the motor or driven equipment that contributes to excessive heating.

3. 5

   Ensure PTC parameters in the VSD (e.g., sensor type, trip thresholds) are correctly configured.