HF damping module: Damping voltage too high

What does 237502 mean?

The damping voltage within the HF damping module has exceeded its alarm threshold. This can be caused by a motor harmonic with high amplitude coinciding with the output filter's resonance frequency, or by the current controller excessively exciting the output filter's resonance. If the damping voltage continues to rise to an unacceptably high level, it will trigger fault F37002 (likely 237002).

• Resonance between motor harmonic frequencies and the output filter (HF damping module) causing voltage amplification.
• Incorrect motor parameters (e.g., P0304, P0305, P0310) entered into the drive, leading to an inaccurate motor model.
• Open circuit or degradation of damping resistors within the HF damping module, impairing its voltage suppression.
• Excessive motor cable length or incorrect cable type, leading to increased reflections and standing waves.
• Output filter component failure (e.g., capacitor degradation, inductor saturation) within the damping module.

Click steps to track your progress.

1. 1

   Verify motor data (P0304-P0310) in the drive parameters against the motor nameplate and correct any discrepancies.

2. 2

   Check parameter P0290 (Motor cable length) and ensure it is accurately set for the installed cable.

3. 3

   Use an oscilloscope to measure the voltage waveform at the drive output terminals (U, V, W) to identify harmonic content.

4. 4

   Inspect the HF damping module for visible damage to components (resistors, capacitors, inductors) or loose connections.

5. 5

   If accessible, measure the resistance of the damping resistors within the module and compare to design values.