When Using a Closed-Loop Stepper Motor, Is There a Way to Suppress the Electromagnetic Interference Generated by the Motor Cable?

Currently, all our closed-loop motors and their extension cables have only the encoder cable equipped with a shield. The motor power cables (including the extension cables used with them) do not have a shield. Considering that some application scenarios have a low tolerance for electromagnetic interference (EMI), we also offer custom shielded cable services. However, this requires additional cost and lead time.

Of course, we also supply raw cable materials, allowing you to make your own shielded cable:

https://www.omc-stepperonline.com/awg-20-high-flexible-with-shield-layer-stepper-motor-cable-cm-20s

In addition to ordering special shielded cables before purchase, the following measures can also effectively suppress EMI from motor cables:

• Add a ferrite core (nickel-zinc material) to the motor cable at the end connected to the driver.
• Ensure good electrical connections between the motor housing, the driver, and the control cabinet's metal plate, and connect them all to a common ground.
• Wrap aluminum foil around the motor cable, covering it as completely as possible from end to end.
• Shorten the cable distance between the driver and the motor as much as possible. Excessively long cables act as "antennas" that radiate interference.
• Separate high-power cables (e.g., motor power cables, mains cables) from low-voltage signal cables (e.g., encoder cables, pulse control signal cables). If space is limited, maintain a separation of at least 10 cm or use a metal partition.

If a single measure cannot effectively suppress the EMI, combine multiple measures according to the actual situation.

Updated on: 28/05/2026