# Voltage of nema17

Hi
In many blocks I find this Nema 17 vor MPCNC:

# STEPPERONLINE 5 Stücke Nema 17 Schrittmotor/Stepper Motor Bipolar 59Ncm 2A 4 Drähte w/ 1m Kabel & Verbinder für 3D DRUCKER/DIY CNC (2,2V)

The Voltage ist 2,2V. Is this right?
Why can I buy a Nema 17 with 2,2v, 3V or 12V?

I want to use: DRV8825 Driver
The CNC V3 Shield get 12V 5A

How manage the Driver the different voltage from the Nema17?
Or is the bandwidth of Nema 17 till 24V?
Motorgröße|Betriebsspannung

Nema 8~Nema 17|12~24VDC

Thanks Volker

The voltage specificatuon is a bit … misleading.

The voltage will be relative to the motor’s inductance, so it has a bearing on how fast the motor can react, but overall, what matters is the current rating.

This is because the stepper drivers regulate the current by varying the dury cycle of the power supply to provide effectively lower voltage until the specified amount of current flows.

Therefore what is required is that your power supply voltage is higher than the motor specified voltage. This is slightly complicated by the fact that the motor itself acts as a voltage generator when it turns, which lowers the available voltage to drive the steppers. This basically limits the maximum speed that the stepper can turn, or at least the available torque at the top end speeds.

Tl;dr: Don’t worry about it. The stepper drivers take care of voltage.

If you were to hook up a DC power supply directly to the motor leads and leave it for a while (motor not turning), the rated voltage is the voltage at which it would overheat. Or stated another way, the rated voltage is the voltage that would produce the rated current given the resistance of the windings.

We don’t use the motors this way, so it does not matter. The motor controller maintains the current below the rated current, and that is enough.

The rated voltage matters for unipolar motors when using a ULN2003 for example because you are basically applying DC through the motor and the current is determined by the supply. But for our purposes the voltage rating can be ignored.