Motor thermistor over temp

What does 11 mean?

The motor thermistor indicates an over-temperature condition, or the thermistor itself may be disconnected or improperly wired. This suggests the motor is overheating, which can lead to severe damage if left unaddressed. Select whether the frequency converter issues a warning or an alarm in 1-90 Motor Thermal Protection.

• Actual motor winding temperature exceeding the thermistor's trip threshold (e.g., 140°C for PTC).
• Open circuit or high resistance in the thermistor wiring (e.g., between terminals 50/51 or dedicated thermistor inputs).
• Short circuit in the thermistor wiring, causing an erroneous low resistance reading (for NTC) or an open circuit reading (for PTC).
• Incorrect selection or faulty thermistor/PTC relay input setting in drive parameters (e.g., P1-90, P1-91).

Click steps to track your progress.

1. 1

   Measure the resistance of the thermistor at the motor connection box, and compare it to the thermistor's temperature-resistance curve.

2. 2

   Check continuity of the thermistor wiring from the motor's terminal box to the drive's thermistor input terminals (e.g., 50/51 or X30/X31).

3. 3

   Inspect the thermistor input terminals on the drive for loose connections, corrosion, or signs of overheating.

4. 4

   Verify parameter P1-90 (Motor Thermal Protection) is set correctly for the thermistor type (e.g., PTC, NTC) and P1-91 (Thermistor Connection) is enabled.