298:1 Micro Metal Gearmotor HP with Extended Motor Shaft
This gearmotor is a miniature high-power brushed DC motor with a 297.92:1 metal gearbox. It has a cross section of 10 × 12 mm, and the D-shaped gearbox output shaft is 9 mm long and 3 mm in diameter. This version also has a 4.5 × 1 mm extended motor shaft.
Key specs at 6 V: 100 RPM and 120 mA with no load, 70 oz-in (5 kg-cm) and 1.6 A at stall.
These tiny brushed DC gearmotors are intended for use at 6 V, though in general, these kinds of motors can run at voltages above and below this nominal voltage, so they should comfortably operate in the 3 – 9 V range (rotation can start at voltages as low as 0.5 V). Lower voltages might not be practical, and higher voltages could start negatively affecting the life of the motor. The micro metal gearmotors are available in a wide range of gear ratios—from 5:1 up to 1000:1—and with four different motors: high-power with long-life carbon brushes (HPCB), high-power with shorter-life precious metal brushes (HP), medium-power (MP), and low-power. The HPCB version (shown on the left in the picture below) can be differentiated from versions with precious metal brushes (shown on the right) by its copper-colored terminals and slightly less shiny case. Note that the HPCB terminals are 0.5 mm wider than those on the other micro metal gearmotor versions (2 mm vs. 1.5 mm), and they are about 1 mm closer together (6 mm vs. 7 mm).
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With the exception of the 1000:1 gear ratio versions, all of the micro metal gearmotors have the same physical dimensions, so one version can be easily swapped for another if your design requirements change. Please see the micro metal gearmotor comparison table for detailed specifications of all our micro metal gearmotors. This dynamically-sortable table can help you find the gearmotor that offers the best blend of speed, torque, and current-draw for your particular application. A more basic comparison table is available below.
Some versions of the gearmotors are available with an additional 1 mm-diameter output shaft that protrudes from the rear of the motor. This 4.5 mm-long rear shaft rotates at the same speed as the input to the gearbox and offers a way to add an encoder, such as our magnetic encoder for micro metal gearmotors (see the picture on the right), to provide motor speed or position feedback.
Note: Stalling gearmotors can greatly decrease their lifetimes, occasionally resulting in immediate damage to the gearbox. This is especially true for the higher gear ratios, such as the 298:1 and 1000:1 versions, which can generate enough torque to damage themselves. The stall torque values given for the two 1000:1 motors are theoretical, and we strongly recommend you avoid stalling them. Prolonged stalls (on the order of seconds) can result in thermal damage to the motor windings and brushes, especially for the versions that use high-power (HP) motors.
Exact gear ratio: 25×34×37×35×3812×9×10×13×10≈297.92:1
Gearmotor Dimensions
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| Micro metal gearmotor dimensions (units in mm). |
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The gearbox has a long (0.365" or 9.27 mm), 3 mm-diameter D-shaped metal output shaft, and the brass faceplate has two mounting holes threaded for M1.6 screws (1.6 mm diameter, 0.35 mm thread pitch). The gearmotor weighs approximately 0.35 oz (10 g). Versions with the extended motor shaft have a 1 mm-diameter round shaft that protrudes 4.5 mm from the rear of the motor, between the two motor terminals; this is not pictured in the above dimension diagram. In terms of size, these gearmotors are very similar to Sanyo’s popular 12 mm NA4S DC gearmotors, and gearmotors with this form factor are occasionally referred to as N20 motors.
The gearbox on the 1000:1 and 1000:1 HP micro metal gearmotors is 12.5 mm long. All of the other micro metal gearmotors have 9mm-long gearboxes, as shown in the above dimension diagram.
