Skip to content


SKU 193321

3321 - 28STH32 NEMA-11 Bipolar Stepper with 27:1 Gearbox

Sold out
Original price €56,01 - Original price €56,01
Original price
€56,01 - €56,01
Current price €56,01

All prices are VAT included

Out of stock
Request Quantity Discount and Information

This NEMA-11 motor has an integrated Planetary gearbox with a 26 103 / 121 :1 ratio. 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 3321 has a maximum speed of 120 RPM. At the output of the gearbox, the step angle approximately 0.067°. When using the step angle in calculations, you should derive the exact step angle by dividing 1.8° by the gearbox reduction ratio.

The 3321 stepper motor connects to a bipolar motor controller such as the 1067 - PhidgetStepper Bipolar HC.

The following table 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.

Wire Color Black Green Red Blue
Board Connector TO B C D

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.

Motor Properties

Motor Type Bipolar Stepper
Manufacturer Part Number 28STH32-0674B / 28JXS40K27
Step Angle 0.067°
Step Accuracy ± 5 %
Holding Torque 16.1 kg cm
Rated Torque 14 kg cm
Maximum Speed ​​(w/1067 Motor Controller) 120RPM
Acceleration at Max Speed
(w/1067 Motor Controller)
1.8E+06 1/16 steps/sec²

Electrical Properties

Recommended Voltage 12V DC
Rated Current 670 mA
Coil Resistance 5.6 Ω

Physical Properties

Shaft Diameter 6 mm
Rear Shaft Diameter 3.9mm
Mounting Plate Size NEMA - 11
Weight 217.5 g
Number of Leads 4
Wire Length 300 mm

Gearbox Properties

Gearbox Type Planetary
Gear Ratio 26 103121 : 1
Backlash Error 1 12 °
Maximum Strength of Gears 20 kg·cm
Shaft Maximum Axial Load 25 No
Shaft Maximum Radial Load 35 No


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.