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SKU 342276

99:1 Metal Gearmotor 25Dx54L mm HP 6V with 48 CPR Encoder

by Pololu
Original price €36,58 - Original price €36,58
Original price
€36,58 - €36,58
Current price €36,58

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This gearmotor consists of a high-power, 6 V brushed DC motor combined with a 98.78:1 metal spur gearbox, and it has an integrated 48 CPR quadrature encoder on the motor shaft, which provides 4741.44 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 6 V: 97 RPM and 550 mA free-run, 210 oz-in (15 kg-cm) and 6.5 A stall.

These cylindrical brushed DC gearmotors are available in a wide range of gear ratios and with five different motors (two power levels of 6V motors and three power levels of 12V motors). The gearmotors all have the same 25 mm diameter case and 4 mm diameter gearbox output shaft, so it is generally easy to swap one version for another if your design requirements change (though the length of the gearbox tends to increase with the gear ratio). All versions are also available with an integrated 48 CPR quadrature encoder on the motor shaft.

Note: Stalling or overloading gearmotors can greatly decrease their lifetimes and even result in immediate damage. For these gearboxes, the recommended upper limit for instantaneous torque is 200 oz-in (15 kg-cm); we strongly advise keeping applied loads well under this limit . Stalls can also result in rapid (potentially on the order of seconds) thermal damage to the motor windings and brushes, especially for the versions that use high-power (HP) motors; a general recommendation for brushed DC motor operation is 25% or less of the stall current.


Size: 25D x 66L mm
Weight: 103g
Shaft diameter: 4 mm

General specifications

Gear ratio: 98.78:1
Free-run speed @ 6V: 97 rpm
Free-run current @ 6V: 550 mA
Stall current @ 6V: 6500 mA
Stall torque @ 6V: 210 oz in 1
Lead length: 8 in 2
Motor type: 6.5A stall @ 6V (HP 6V)
Encoders?: Y


1 This is a theoretical value; stalling the gearbox output shaft is likely to damage the gearbox.
2 May vary by a few inches.

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