Back EMF Test in Servo Motor Repair and Maintenance

The Back EMF test is performed to detect potential power losses that may occur in the rotor magnets of long-running synchronous servo motors due to the heat they are exposed to.

The power losses occur in the magnets of the rotor of synchronous servo motors as a result of the heat they are exposed to, which is dependent on the current they draw. This situation leads to power (torque) loss in the motors. The servo motor draws more current to perform its work, resulting in more heat generation, and over time, the magnets lose more power and become unable to function properly.

In response to this issue, customers often report power loss, torque loss, thermistor errors, and overheating complaints.

As part of the repair and maintenance process, all synchronous servo motors that come to our workshop undergo a Back EMF test to identify potential magnet problems.