Troubleshooting

The following table is to be seen as a “First Aid” box. There can be a large number of different reasons for a fault, depending on the particular conditions in your system. The fault causes described below are mostly those which directly influence the motor. Peculiarities which show up in the control behavior can usually be traced back to an error in the parameterization of the servo drives.

Information about this can be found in the documentation for the servo drives and the commissioning software.

Error

Possible cause

Measures to remove the cause of the fault

Motor does not move

  • Servo drive not enabled
  • Break in setpoint lead
  • Motor phases in wrong sequence
  • Brake not released
  • Drive is mechanically blocked
  • Apply ENABLE signal
  • Check setpoint lead
  • Correct the phase sequence
  • Check brake control
  • Check mechanism

Motor runs away

  • Motor phases in wrong sequence
  • Correct the phase sequence

Motor oscillates

  • Break in the shielding of the feedback cable
  • Amplification to high
  • Replace the feedback cable
  • Use the motor default values

Error message: brake

  • Short-circuit in the supply voltage lead to the motor holding brake
  • Voltage too low
  • Faulty motor holding brake
  • Eliminate short-circuit

  • Increase the voltage
  • Replace the motor brake

Error message: output stage fault

  • Motor cable has short circuit or earth leakage
  • Motor has short circuit or earth leakage
  • Replace motor cable
  • Replace motor

Error message: feedback

  • Connector is not properly plugged in
  • Break in cable, cable crushed or similar
  • Internal error
  • Check the plug connector
  • Check cables
  • Read out the error messages

Brake does not grip

  • Required holding torque too high
  • Brake faulty
  • Check the design
  • Replace the motor brake


For multi-axis systems there may be further hidden reasons for faults.