EL
ErrorLib
Brands
||
  1. Home
  2. Danfoss
  3. VLT AutomationDrive FC 301/302
  4. 20
About·Privacy·Terms

ErrorLib — Industrial Fault Code Library

Disclaimer: ErrorLib is an independent technical reference tool. While we aim for accuracy, always verify with the manufacturer’s official service manuals before performing maintenance on industrial equipment. ErrorLib is not affiliated with the brands listed.

20

Temperature input error

Danfoss · VLT AutomationDrive FC 301/302

What does 20 mean?

The temperature sensor connected to the drive's input is either not detected, improperly connected, or providing an invalid signal. This prevents the drive from accurately monitoring temperature.

Common Causes

  • Disconnection or open circuit in the temperature sensor wiring connected to the drive's analog input terminals (e.g., 53/54).
  • Faulty temperature sensor (e.g., PT100, NTC thermistor) providing an out-of-range signal (e.g., too high or too low resistance).
  • Incorrect wiring of the sensor to the drive's terminals (e.g., 2-wire sensor connected to 3-wire input, reversed polarity).
  • Drive's analog input parameter (e.g., P6-10 Sensor Type, P6-11 Low Value) incorrectly configured for the specific sensor type.
  • Damage to the drive's analog input circuit on the control board, preventing accurate signal reading.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Power down the drive, disconnect the temperature sensor wires from the drive's input terminals (e.g., 53/54).

  2. 2

    Measure the resistance of the temperature sensor across its leads; compare to the sensor's specified temperature/resistance curve (e.g., PT100 should be 100 Ohms at 0C).

  3. 3

    Inspect the entire length of the sensor wiring for breaks, insulation damage, or loose connections.

  4. 4

    Verify the analog input configuration parameters (e.g., P6-10 Analog Input Type, P6-11 Analog Input Low Value, P6-12 Analog Input High Value) are correct for the installed sensor.

  5. 5

    Temporarily connect a known good reference resistor (e.g., 100 Ohm for PT100) to the input terminals to simulate a valid sensor reading.

Browse all codes in this manual (66)
Verified technical data. Last updated: April 2026

Related Faults

#14Earth (ground) fault#32Motor phase W missing#36Mains failure
Source: Danfoss VLT AutomationDrive FC 301/302
View Official PDFSearch more codes in this manual