Stepper motors have high torque to hold position but AC servo motors have much faster travel speed as well as high torque. Also with feedback loop servo motors keep accurate position within 5thou. In this example, both machines are running at full speed. Servo CNC on the right travels 2500 inches per minute with 50 in/sec2 acceleration while stepper runs at 900 inches per minute max speed without stalling at 20 in/sec2 acceleration
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