Deflection

Command

<axis> DFL

Description

The Deflection command is an indirect measurement of the torque being applied to the motor shaft available when the motor is in tracking mode. The numeric range of Deflection is from -1 to 1. If there is no applied torque the rotor will closely align with the null torque position of the motor field and have no deflection. As torque is applied the rotor will move from this nominal position like a spring. The Deflection register value will increase in magnitude up to a magnitude of 1 when the maximum torque is being applied. If the rotor is displaced beyond this maximum torque location the rotor will move but because of the tracking effect the field will move with it sustaining maximum torque. In this condition the deflection will either be 1 or -1 depending on the direction of the applied torque. When the applied torque is reduced the rotor will return to the nominal position and the deflection will move back to 0.

Deflection is different from Rotor Lead Lag. Rotor Lead Lag indicates how much the motor field has rotated to prevent the motor from stalling. Deflection is how much the rotor has been moved within a single step.

Escapes

Reading deflection does not produce any escapes.

Examples

The following command reads the deflection of an unloaded motor shaft:

Related Topics

Tracking
Rotor Lead Lag