Servodisc Brush Replacement Comments

Unlike our other brush motor products, Kollmorgen does not sell replacement brushes for our Servodisc motors.

Servodisc motors are a unique product where the brushes can outlast other parts of the motor such as the commutator. Typically, the first item that wears out is the commutator, not the brushes. The commutator surface on Servodisc motors is very thin.  If about 2/3 of the layer wears down, then the armature is basically shorted...we've done life testing to verify this. This happens after about 1.2 Billion revolutions. If you ran the motor 24/7 at rated speed of 3,000 RPM, life expectancy is approximately 280 days. This can vary depending upon the application. Obviously, if the motor runs intermittently, or at slower speeds, then the life expectancy goes up

Also, they are difficult to take apart and reassemble, and there is no easy way to replace the brushes on them. To replace the brushes the motor has to be completely disassembled. This is due to the brushes being axially (parallel to the shaft) placed within the motor, not radially (perpendicular to the shaft) placed from the outside like standard brush motors.

For these reasons we do not sell brush kits for servodisc motors and only do in house repairs. We recommend returning the motor via RMA to evaluate the motor and replace the armature and brushes if needed.  Another option would be to purchase a new motor.