When you look for this answer, many pages on google you searched out may give you lots of data, and official explanation about the definition of stepper motor, servo motor, torque, terminology such words you may not familiar at all. And you feel so uncomfortable, do I have to study these very well, then can come to know which cnc router configuration I should choose for best choice? Stepper motor or servo motor?
Servo Motor
Stepper Motor
I believe there must a way which can tell user how to choose, and this way must be much easier for user to understand and considering user’s benefit. Yes, it is. I am a file mover, I also searched a lot on google and listed some points of difference for servo and stepper, hope it is easier for cnc router purchaser to understand.
if only considering this point, stepper is winner, its cost is lower than servo motor that has same power rating. Servo motor is more expensive, especially servo motors made in Japan, Germany . Servo motor we use is made in Japan, which is rather expensive than stepper motor made in China. Well, the stepper motor company we use is also cooperated with the manufacturer from Germany.
Servos are excellent in applications requiring speeds greater than 2,000 RPM and for high torque at high speeds or requiring high dynamic response. Steppers are excellent at speeds less than 2,000 RPM and for low to medium acceleration rates and for high holding torque.
Because of the way stepper motors are constructed and operate they have very good repeatability with little or no tuning required. Servo motors can have very good repeatability if setup correctly. The encoder quality can also play into repeatability. So if you requires high precision work, we suggest you servo motor and driver to purchase.
Servo motors are very efficient. Yielding 80-90% efficiency given light loads. Stepper motors consume a lot of power for outputting, much of that is converted to heat. Stepper motors are usually about 70% efficient. This is also a good feature help you to decide which one to choose.
Because the current draw of a servo motor is proportional to the load applied, heat production is very low comparing stepper motor. Stepper motors draw excess current regardless of load. The excess power is dissipated as heat.
Servo motors produce very little noise. Stepper motors produce a slight hum due to the control process. However OMNI offer high quality driver, and it will decrease the noise level.