CU: Temperature sensor fault

What does A03520 mean?

An error occurred during evaluation of the temperature sensor, which is expected to be an Ni1000 or PT1000 connected via an analog input (AI2 or AI3). Possible causes include wire breakage, the sensor not being connected, or a short circuit leading to a measured resistance that is too low. This can result in inaccurate temperature monitoring and potential overheating if not addressed.

• Open circuit (wire breakage) in the temperature sensor cable connected to analog input AI2 or AI3.
• Short circuit in the temperature sensor cable or sensor element itself (e.g., Ni1000, PT1000).
• Incorrect sensor type configured in drive parameters (e.g., P0601, P0602 for sensor type) not matching the physical sensor.
• Analog input terminal (e.g., AI2, AI3) on the control unit is defective or miswired.
• Loose connection at the control unit's analog input terminals (e.g., X124 terminal block) or sensor terminals.

Click steps to track your progress.

1. 1

   Power down the drive system and disconnect the temperature sensor from AI2 or AI3 terminals (e.g., X124).

2. 2

   Measure the resistance of the temperature sensor directly at its terminals using a multimeter (e.g., PT1000 should be ~100 Ohms at 0°C, Ni1000 ~1000 Ohms at 0°C).

3. 3

   Check the continuity of the sensor wiring from the sensor to the drive's AI2/AI3 terminals (e.g., X124 pin 6, 7, 8).

4. 4

   Verify the temperature sensor type parameter (e.g., P0601 or P0602 for the specific AI) matches the installed sensor (e.g., set to 1 for Ni1000 or 2 for PT1000).

5. 5

   If possible, connect a known good sensor to the AI2/AI3 terminals and check if the alarm clears.