47:1 Metal Gearmotor 25Dx52L mm MP 12V with 48 CPR Encoder
This gearmotor consists of a medium-power, 12 V brushed DC motor combined with a 46.85:1 metal spur gearbox, and it has an integrated 48 CPR quadrature encoder on the motor shaft, which provides 2248.86 counts per revolution of the gearbox’s output shaft. The gearmotor is cylindrical, with a diameter just under 25 mm, and the D-shaped output shaft is 4 mm in diameter and extends 12.5 mm from the face plate of the gearbox.
Key specs at 12 V: 160 RPM and 200 mA free-run, 85 oz-in (6 kg-cm) and 2.1 A stall.
In general, these kinds of motors can run at voltages above and below their nominal voltages; lower voltages might not be practical, and higher voltages could start negatively affecting the life of the motor.
|Size:||25D x 64L mm|
|Shaft diameter:||4 mm|
|No-load speed @ 12V:||160 rpm|
|No-load current @ 12V:||200 mA|
|Stall current @ 12V:||2100 mA|
|Stall torque @ 12V:||85 oz·in|
|No-load speed @ 6V:||80 rpm1|
|Stall current @ 6V:||1050 mA1|
|Stall torque @ 6V:||42 oz·in1|
|Lead length:||8 in2|
|Motor type:||2.1A stall @ 12V (MP 12V)|
1This motor will run at 6 V but is intended for operation at 12 V.
2May vary by a few inches.
MATLAB script to plot motor performance curves for Pololu brushed DC gearmotors
This MATLAB script, written by Ali Asgher Mansoor Habiby, plots speed, power, current draw, and efficiency as they vary with torque when you input the gearmotor specifications. It also prints the resistance of the motor, and the current draw and torque at which maximum efficiency and maximum power occur.