Variable Frequency Spindle Drives are motor controllers that adjust the speed for your spindle motor. Specifying the right variable drive is important. When doing so, you help minimize downtime, optimize energy consumption, system efficiency, and reduce stress on your machinery, helping them remain in service longer. GTI can provide variable frequency spindle drives (VFDs) for any motorized spindle application. They can be specified based upon source power, horsepower, speed and torque needs as well as environment, mounting and enclosure configurations.