NEMA 42 Stepper Motors

ATO offers two series of NEMA 42 stepper motors: One is 2 phase 4 wires bipolar nema 42 stepper motor with 1.8 degree step angle, another one is 3 phase 6 wires nema 42 stepper motor with 1.2 degree step angle. They provide high holding torque in many industrial applications. The price we present to you will be lower than other online shops.

Stepper motor FAQs

What is holding torque?

Holding torque refers to the torque at which the stator locks the rotor when the stepper motor is energized but not rotating. It is one of the most important parameters of the stepper motor, usually the torque of the stepper motor at low speed is close to the holding torque. Since the output torque of the stepper motor decreases with the increase of speed, and the output power also changes with the increase of speed, the holding torque has become one of the most important parameters to measure the stepper motor. For example, when users need a 2N.m stepper motor, they refer to a stepper motor with a holding torque of 2N.m unless otherwise specified.

What is detent torque?

Detent torque refers to the torque at which the stator locks the rotor when the stepper motor is not energized.

How accurate is the stepper motor? Does it accumulate?

Generally, the accuracy of the stepper motor is 3-5% of the stepping angle, and it does not accumulate.

What is the allowable surface temperature of the stepper motor?

If the temperature of the stepper motor is too high, the magnetic material of the motor will be demagnetized, resulting in a decrease in torque and even loss of step. Therefore, the maximum temperature allowed on the surface of the stepper motor should depend on the demagnetization point of the magnetic material. Generally speaking, the demagnetization point of the magnetic material is above 130℃, and some are even as high as 200℃, so the surface temperature of the stepper motor is completely normal at 80-90℃.

Why does the torque of the stepper motor decrease as the speed increases?

When the stepper motor rotates, the inductance of each phase winding of the motor will form a back electromotive force. The higher the frequency, the greater the back electromotive force. Under its action, the phase current of the motor decreases as the frequency (or speed) increases, resulting in a decrease in torque.

How to reduce the vibration and noise of the 2 phase hybrid stepper motor at low speed?

• If the stepper motor just works in the resonance area, you can avoid the resonance area by changing the mechanical transmission such as the reduction ratio.
• Adopt the driver with subdivision function, which is the most commonly used and easiest method.
• Change to a stepper motor with a smaller step angle, such as a 3 phase or 5 phase stepper motor.
• Switching to AC servo motor can almost completely reduce vibration and noise, but the cost is higher.
• Add a magnetic damper to the motor shaft.