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I have a Prusa MK2.5 which runs at 12 V, the Prusa MK3 runs at 24 V.

I noticed that on Prusa's webpage, they list the stepper motors as being compatible with both the MK2 and the MK3 even though they run at different voltages.

My question is: are stepper motors typically tuned for specific voltages (like most fans are), or are these stepper motors compatible with both 12 and 24 V systems?

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    $\begingroup$ if they say its compatible, chances are high that a current limiter on the motor controller is expected to take effect and prevent frying if set correctly for the motor. check controller. big ones have a set of switches. little ones have a trim pot. $\endgroup$
    – Abel
    Dec 19, 2021 at 22:14
  • $\begingroup$ if you use two power supplies.... toms3d.org/2019/05/25/use-the-wrong-parts-on-any-3d-printer $\endgroup$
    – Trish
    Jan 24 at 0:00
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    $\begingroup$ There is an excellent answer found on SE Electronics! Basically there is a difference between the constant voltage applied or one applied through a sophisticated controller! The stepper is probably rated for 4 V (continuous) or something close to that, a good rule of thumb is to use between 10 and 24 times the motor’s nameplate voltage, so it will work at 40~80 V. $\endgroup$
    – 0scar
    Jan 25 at 15:17

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The steppers have two voltages in the specifications: nominal voltage and maximum voltage for the electrical insulation between windings.

The nominal voltage is basically never that high. The motors from Prusa are likely rated at 4-5 V operating voltage: the voltage you apply from the control board is higher, but as soon as the current reaches the value you set, the chip starts cutting intermittently the voltage, so 12-0-12-0-12... and the average value never goes above those 4-5 V.

The second value, the insulation, is the one you must NEVER exceed, even when operating intermittently, but it is likely 30 V or more.

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Without having the exact model number of the motor to check the data sheet, this can't be answered. Glancing at the link you supplied, I didn't see either a data sheet or a model number I could use to get a data sheet.

Typically stepper motors overheat when they are run at too high of a voltage. However, the advertised voltage for the motor could be the lowest voltage at which it works.

For a real answer, you'd have to look at the manufacturer's datasheet for the motor, which should include minimum and maximum voltages and graphs showing current vs. voltage vs. force graphs, and possibly duty cycle graphs.

Also, in some cases, if you run a motor at a higher voltage than it is rated for, it may produce back EMF that is larger than the motor controller is prepared for, and it could burn out the controller. However, if the controller is designed for 24v, this is less likely of a problem.

Note also that there are conversion kits, where you place a small board between the controller and the motor that fixes the voltage for the motor.

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