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Motor controller fails to start with Estop error: "MC: Position estimator or encoder invalid, ictl st 2.000, error info 10.00"

The encoder or estimator are not initialised yet. Ensure a 'start' parameter is issued before starting the alignment procedure. See Rotor Position Alignment section.

Motors with high cogging torque

Some combinations of motor poles and slots produce high cogging torques. Depending on the severity of the cogging torque it may not be possible to perform certain motor control tasks, such as:

  • Encoder linearisation,
  • Satisfactory speed control at low speeds,
  • Satisfactory position control without applying very high gains.

There is not much to be done for the encoder linearisation task, and this may task may have to skipped for motors with high cogging torque. However, JCS motor cogging compensation can help significantly with the speed and position control.