Stepper Motor 101

Stepper Motors Are Constant Power Devices. They Are Brushless, Electric Motors Capable of Dividing Complete Rotations into a Sizeable Number of Steps

Katherine BonfanteBy Katherine Bonfante, Managing Editor, Digital Media

When it comes to designing and integrating industrial machines—or any machine at all—I'm not an expert. To me, a motor is something noisy that makes a machine run. I honestly don't know how it works or what the difference is between one motor and another. All I know is that if they are working properly the machine probably will get the job done.

Asking around my pool of experts, I found out that stepper motors are constant power devices. They are brushless, electric motors capable of dividing complete rotations into a sizeable number of steps. Stepper motors can be controlled without any feedback mechanism, but they must be sized properly, according to the application.

I logged on to to learn more about these devices, and found a number of informative articles and white papers that helped me to better understand these industrial components.

Executive editor Jim Montague wrote "Invasion of the Stepper Motors," in which he explains how developers have added new capabilities to stepper motors and how they are now using these in a broad range of applications. Some developers even push stepper motors into servo-motor territory, he details.

This article also explains how Roger Klish, owner of Machine System Integrators in St. Paul, Minn., used stepper motors at the University of Minnesota's Bell Museum of Natural History to animate a gopher within one of the museum's exhibits when visitors walk by. Read the article at to learn more about this project.

Guest writer Don Talend wrote "Step Into a Niche," in which he covered how stepper motor performance has a suitability for high-speed applications that require substantial precision. High-speed, precision industrial applications benefit from the latest advancements made in stepper motor technology, Talend says.

Some of the proper uses that Talend talks about in his article include label application and cylindrical plastic joint welding. The niche that these motors have found in high-volume applications goes beyond variable reluctance (VR) and permanent magnet (PM) designs. Read this article at to learn more about the niche and the benefits stepper motors bring.

You can also visit our Machine Builder Forum ( to tell us what you know about stepper motors. Post your questions or share your expertise.

Do you use steppers for applications where others might choose to use servos these days? Let us know by logging on to our forum at and sharing your story.

To learn more about stepper motors, visit our online library at and read the latest articles, news, white papers and products on this subject.