Closed Loop Calibration

The calibration procedure executes each time the closed loop is enabled. The calibration procedure aligns the stator position with the motor shaft position. During this calibration procedure, the motor shaft must be able to move freely. The motor will move slightly at very low speed.

You can view the feedback status In the Drive_Diagnostic > Feedback_Status window.

If the Feedback_Active LED is green, the system is working in closed loop. Otherwise a red LED indicates a potential issue. See the object Feedback_Status for details.


The calibration procedure is necessary to align the encoder mounted on the motor rear shaft at the stator position.

Two calibration procedures are available:

  • Feedback_Calibration_Full

  • Feedback_Calibration Light

Feedback_Calibration_Full

In this modality, the motor shaft moves slightly. The motor shaft must be free to move.

During the procedure, the system recognizes if the motor is on mechanic limit and tries to move in the opposite direction. After each switch-on of the drive, this procedure should be executed to activate the closed loop.

TheFeedback_Status.Full Calibration bit and Feedback_Status.Active bit are set after a sequence is successfully executed.

Feedback_Calibration_Lite

In this modality, the motor shaft does not move. This is only done when the alignment between the stator position and the rotor position without the motor shaft is moved.

The Feedback_Status.Active bit is set when a sequence is successfully executed.

The Feedback_Status.Full_Calibration_Done bit gives information about the execution of the Feedback_Calibration_Full procedure.

Some considerations

The calibration procedure is executed in the following conditions:

The Feedback_Status.Full_Calibration_Done bit is cleared if Error_Register.Motor_Feedback_Error is set together with one of these alarms: