How to Limit the Output Torque of a Stepper Motor?

There are three main methods to limit the output torque of a stepper motor:

1. Adjust the Driver's Output Current

his is the most direct method. By reducing the current that the driver supplies to the motor, you lower the motor's output torque. The vast majority of drivers on the market provide either external DIP switches (as shown in the figure) or software tuning options to adjust the output current. If you feel the current motor torque is too high, you can reduce it by a few steps.

Disadvantage: This method reduces torque across the entire speed range.

2. Use the Driver's Torque Limiting Function

This is a smarter method, implemented by the driver's internal algorithm. By setting a parameter (e.g., torque limit percentage) via tuning software, the motor's output torque will not exceed the limit regardless of the stepper motor's speed.

Disadvantage: This method requires an advanced driver. The vast majority of pulse-type controllers do not support this function. Only some high-end custom drivers offer it, resulting in a higher cost.

3. Reduce the Motor Speed

Due to the inherent torque-speed characteristic of stepper motors (torque is inversely proportional to speed – the higher the speed, the lower the torque), reducing the motor speed is another direct method. Refer to the motor's torque curve, find the speed corresponding to your desired torque, and adjust accordingly.

Disadvantage: This method is not suitable for constant-speed applications, as speed changes may cause adverse effects.

In summary, please choose the most appropriate method based on your actual operating conditions.

Updated on: 28/05/2026