Error Position

Motion Block

Description

Error Position returns the difference between where the motor is commanded to be and its Actual Position. For a stepper motor the Actual Position is the number of counts that have been transmitted to the drive section so the Error Position is reporting how well the electronics is expressing the trajectory. For a servo motor the Actual Position is the motor shaft position as reported by the encoder. In this case the Error Position reports how well the motor is physically tracking the trajectory. The Error Position is monitored and if it is found to be greater than the Error Limit, the motor is turned off. The Error Limit can be changed with the Set Error Limit block.

Escapes

The Error Position block does not produce any escapes.

Examples

This Show Event displays the error position

Plotting the error position of a servo indicates how well the motor is performing. This block list is from the Scope Package. Indicating Error Position for the scope probe assignment makes this the information that will be shown:

Related Topics

Error Limit
Set Error Limit
Actual Position
Commanded Position
Destination Position
Capture Position