# Tic voltage ratings

hello,

Being New to this subject and needing the max torque i could get out of stepper motors, I picked the largest tic motor controllers to play with. however, I have noticed that it is impossible to get stepper motors that go as high as 40 volts. so, what am I missing here?

thank you,

Hello.

It sounds like you are just looking at the rated voltage specification for some stepper motors. Is that correct? Or are you actually measuring something with an actual system, in which case can you post more details and some pictures?

In general, stepper motor’s typically have relatively low voltage ratings, but you can power them from higher voltages as long as you are using a stepper motor or controller with properly configured active current limiting. By using a higher voltage along with active current limiting, the current is able to ramp up faster, which lets you achieve higher torques and step rates than you could using the rated voltage.

The most important thing you can do to get the maximum possible torque from a stepper motor is to make sure you select a driver or controller, power supply, and motor that will work well together. There is guidance about that in the “Choosing the power supply, Tic, and stepper motor” section of the Tic user’s guide.

- Patrick

Hello Patrick,

Yes you are correct, I am going with the motor’s rating. it is confusing since i assumed that it would be an specific rating or at least max rating. it seems like it is really the minimum voltage required. thank you for the explanation and I have a question about the torque. the motor spec shows a torque value which I am assuming is related to the rated voltage. how would I go about calculating the torque if I am providing voltage way higher than the spec. the motor is rated for 2.5V and I am planning to provide 40V. do I assume that the 40 volt is the actual number and calculate the torque from there or do i need to use some type of coefficiency factor?

thank you again,

Unfortunately, there is not a straightforward way to calculate how much torque you will be able to get from your stepper motor since it depends on several factors such as the supply voltage, your target step rate, the current limit, the microstepping mode, the driver you are using, and how the driver is configured. The best way to get a sense of what the motor can do is typically by looking at a pull-out torque curve for it. Those are usually provided for our stepper motors in the manufacturer’s datasheet, which is available on the motor’s product page under the “Resources” tab.

- Patrick