Rated Voltage vs Torque Curve

Newbie question:
The SY20STH42-0804A stepper motor data sheet states rated voltage of 4.32v but the Torque Curve is calculated at 24v.
Am I missing something? Isn’t rated voltage kind’a like the max voltage? I don’t see anything on the data sheet that would suggest you can safely apply 24v.
Sorry if this is an obvious question but it puzzles me.

Hello, John.

For stepper motors, the rated voltage is the voltage at which each coil draws the rated current. When you are using a current limiting driver (like any of our stepper motor drivers or Tic controllers), you can safely use a higher operating voltage. By using a higher voltage in combination with active current limiting, the current is able to ramp up faster, which lets you achieve higher step rates than you could using the rated voltage.


Thanx for the reply. Got a lot to learn about steppers and controllers.

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