Feature

Stepper motor vs servo motor: Which is right for your application?

In today’s industrial marketplace, it can be confusing and challenging to choose the correct motor for an application. As well as all the different types of motor, the information provided on each is often either too basic or too technical to be helpful. In this article, Mike Keefe of KEB America explains the differences between stepper and servo motors, and when it is appropriate to use each technology.

04/01/2022 16:06:14

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A stepper motor is a type of brushless DC motor. It is designed to provide a certain number of defined steps per revolution. For example, a motor with 200 steps/revolution will offer a position resolution of 1.8°/pulse (360°/200 pulses). Each time
the motor is pulsed by the stepper controller, it will move in the forward or reverse direction, according to the number of pulses received. In the aforementioned example, 100 pulses would cause the motor to rotate 180°.

Advantages of stepper
motors

A stepper motor is able to offer open-loop positioning, which is a big advantage over open-loop induction motors, which are not able to provide positioning. Most stepper motors do not include any feedback, which lowers the overall cost of a stepper
and control solution. Their low cost is a primary reason for their widespread use. One advantage in industrial applications is that stepper motors can be run with a DC-powered stepper drive. They do not require larger inverters that input 230/460VAC, or
bulky fusing and cabling, which can be quite significant with multi-axis applications.

Limitations of stepper motors

It is possible for a stepper to ‘lose’ position. This can happen if it does not provide sufficient torque to move the shaft and load...

Read the full article in DPA's January issue

Written By Sophia Bell

Sophia Bell is the Group Editor of DPA, Connectivity, and PBSI. She joined the team in 2020 as Assistant Editor after achieving a First-Class Honours BA in English Literature and Film Studies from the University of East Anglia. In her current role, she leads the editorial strategy, driving digital growth and ensuring each title continues to deliver trusted, relevant insight for engineering and manufacturing professionals.