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Brushless servo motors are being used in industry for many different applications. However, the primary industrial use for these motors is in automated machinery for the accurate positioning of the workpiece or work tool. The brushless servo motor will have many features that are different than the standard AC induction or brush type DC motor. Most service centers are familiar with the operation and characteristics of three-phase induction motors and with DC motors with a commutator and brushes.

For years, electric motor repair facilities have been routinely rewinding the common three-phase electric motor. With the complexity of some of the newer technologies, the chance for error is signifcantly increased. We have had to become more observant and heighten our awareness. Here are a couple of examples that one service center encountered, and where we were able to identify the data and rewind the motor successfully.

Brushless servo motors ARE electric motors; therefore many of the tools needed to test them are already available in an electric motor service center. In this article, we've listed some instruments and tools that will be needed to service servo motors.