3320_0 - 28STH32 NEMA-11 Bipolar Gearless Stepper Motor


This tiny stepper with a rear shaft has a 1.8° step angle and 520 g·cm of torque at low speeds.

Product Description


This NEMA-11 motor generates 600 g-cm of holding torque at 0.67 Amps. It comes with the rear shaft exposed, so you can mount an encoder or shaft coupler.

When connected to a 1067 - PhidgetStepper Bipolar HC, the 3320 has a maximum speed of approximately 426 RPM.


Motor Controller and Connection


The 3320 stepper motor connects to a bipolar motor controller such as the 1067 - PhidgetStepper Bipolar HC.

The following diagram shows how to connect the motor wires to the board connectors to produce a clockwise rotation in the stepper motor when increasing position. To wire for counter-clockwise rotation when increasing position, reverse the red and blue wires.


Note: Make sure to unplug the power cord from the motor controller before switching wires around.

The rear shaft of this motor can be equipped with the HKT22 Optical Encoder for applications where you need to keep track of the exact position, velocity, or acceleration of the motor.



Mounting Bracket


The mounting holes on this motor are compatible with the 3337 - Mounting Bracket (NEMA11).


Product Specifications


Motor Properties

Motor Type Bipolar Stepper
Manufacturer Part Number 28STH32-0674B
Step Angle 1.8°
Step Accuracy ± 5 %
Holding Torque 600 g·cm
Rated Torque 520 g·cm
Maximum Speed (w/1067 Motor Controller) 426 RPM
Acceleration at Max Speed
(w/1067 Motor Controller)
2.2E+06 1/16 steps/sec²


Electrical Properties

Recommended Voltage 12 V DC
Rated Current 670 mA
Coil Resistance 5.6 Ω
Phase Inductance 3.4 mH


Physical Properties

Shaft Diameter 5 mm
Rear Shaft Diameter 3.9 mm
Mounting Plate Size NEMA - 11
Weight 111.4 g
Number of Leads 4
Wire Length 300 mm




warning Connecting the motor directly to a power supply will destroy the motor and void the warranty. If you want to check your motor make sure it is connected to a constant current / chopper drive controller.