Stepper Motor Technical Note: Determining Torque Sensitivity And Holding Torque Of Two Phase Permanent Magnet Stepper Motors

Frequently the torque sensitivity of a two-phase stepper motor is not specified in the vendor's published literature. This important, intrinsic stepper motor parameter is easily calculable.

One method to determine the torque sensitivity is utilizing the specification or measurement of the back emf in volts/(k steps/sec) and the full step angle. Often, a stepper motor vendor specifies the back emf and step angle. In any case, both are easily ascertained by testing.