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SKU 342827

2827 - 131:1 Metal Gearmotor 37Dx73L mm with 64 CPR Encoder

by Pololu
Original price €42,14 - Original price €42,14
Original price
€42,14 - €42,14
Current price €42,14

All prices are VAT included

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This gearmotor is a powerful 12V brushed DC motor with a 131.25:1 metal gearbox and an integrated quadrature encoder that provides a resolution of 64 counts per revolution of the motor shaft, which corresponds to 8400 counts per revolution of the gearbox's output shaft. These units have a 0.61"-long, 6 mm-diameter D-shaped output shaft.

Key specs at 12 V : 80 RPM and 300 mA free-run, 250 oz-in (18 kg-cm) and 5 A stall.

These motors are intended for use at 12 V, though in general, these kinds of motors can run at voltages above and below the nominal voltage (they can begin rotating at voltages as low as 1 V). Lower voltages might not be practical, and higher voltages could start negatively affecting the life of the motor.

Using the Encoder

A two-channel Hall effect encoder is used to sense the rotation of a magnetic disk on a rear protrusion of the motor shaft. The quadrature encoder provides a resolution of 64 counts per revolution of the motor shaft when counting both edges of both channels. To compute the counts per revolution of the gearbox output, multiply the gear ratio by 64. The motor/encoder has six color-coded, 11" (28 cm) leads terminated by a 1×6 female header with a 0.1″ pitch, as shown in the main product picture. This header works with standard 0.1″ male headers and our male jumper and precrimped wires. If this header is not convenient for your application, you can pull the crimped wires out of the header or cut the header off. The following table describes the wire functions:

Color Function
Red motor power (connects to one motor terminal)
Black motor power (connects to the other motor terminal)
Green GND encoder
Blue Vcc encoder (3.5 – 20 V)
Yellow A output encoder
White encoder B output

The Hall sensor requires an input voltage, Vcc, between 3.5 and 20 V and draws a maximum of 10 mA. The A and B outputs are square waves from 0 V to Vcc approximately 90° out of phase. The frequency of the transitions tells you the speed of the motor, and the order of the transitions tells you the direction.


Size: 37D x 72.5L mm 1
Weight: 235 g
Shaft diameter: 6 mm

General specifications

Gear ratio: 131:1
Free-run speed @ 6V: 40rpm 2
Free-run current @ 6V: 250mA 2
Stall current @ 6V: 2500mA 2
Stall torque @ 6V: 125 oz in 2
Free-run speed @ 12V: 80 rpm
Free-run current @ 12V: 300 mA
Stall current @ 12V: 5000 mA
Stall torque @ 12V: 250 oz·in
Lead length: 11 in


1 Length measurement does not include gearbox shaft or the raised area immediately around it.
2 This motor will run at 6 V but is intended for operation at 12 V.