Motor thermistor overtemp
Danfoss · VLT HVAC Drive High Power
Was bedeutet ALARM 11 ?
The motor thermistor indicates an overtemperature condition, or it may be disconnected. The frequency converter can be configured to issue either a warning or an alarm based on parameter 1-90 Motor Thermal Protection. This fault protects the motor from thermal damage.
Häufige Ursachen
- Motor operating under excessive mechanical load, leading to winding overtemperature.
- Motor cooling fan failure or obstructed cooling fins.
- Thermistor cable breakage or loose connection at the motor or frequency converter terminals (e.g., terminals 53, 54, 55, or dedicated thermistor inputs).
- Faulty motor thermistor (PTC, NTC, KTY) sending an incorrect resistance signal.
- Incorrect parameter setting for P1-90 (Motor Thermistor Function) or P1-91 (Thermistor Source).
Reparaturschritte & Checkliste
Klicken Sie auf Schritte, um Ihren Fortschritt zu verfolgen.
- 1
Verify the motor temperature using an external non-contact thermometer to confirm actual overtemperature.
- 2
Measure the resistance of the motor thermistor at the frequency converter's thermistor input terminals (e.g., 53/54, or specific AIN) and compare to its datasheet values.
- 3
Check the wiring continuity and connections of the thermistor cable from the motor to the frequency converter.
- 4
Inspect the motor's cooling fan and cooling fins for blockages or damage.
- 5
Review parameter P1-90 (Motor Thermistor Function) to ensure it is correctly enabled and configured for the thermistor type.
- 6
Reduce the mechanical load on the motor or verify its sizing for the application.