Pololu High Power N20 Motor 6V
N20 Motors are tiny brushed DC motors with integrated gearboxes. N20s are compact and lightweight and extremely useful for fairyweights and antweights. The Pololu N20 High Power Motor is a miniature high-power, 6 V brushed DC motor with a 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.
N20s are staples in the UK and are becoming more popular in the US as fairyweight robots become more common and lowering the motor weight to allow more weight to be devoted to weapons is more of a priority. They are a classic from the early days of robot combat and they are still very common today. The combination of relatively low cost, minimal weight plus power makes them ideal for US fairyweight bots. They have also been used with success for US antweight bots, depending on the gear ratio.
Physical Specifications for Pololu N20 High Power Motor
|Output Shaft Style||D-shaft|
|Motor Type||Brushed DC|
|Output Shaft Support||Brass Case|
|Gearbox Style||Straight Cut Spur|
|Connector Type||Male Spade Terminal|
|Total Length:||26mm, with shaft 40mm|
|Gearbox Diameter:||12mm x 10mm|
|Mounting Holes (2):||M1.6 9mm apart|
Operating Specifications for Pololu N20 High Power Motor
|No-load speed @ 6V:||590 rpm3|
|No-load current @ 6V:||0.10 A4|
|Stall current @ 6V:||1.6 A|
|Stall torque @ 6V:||0.86 kg·cm|
|Max output power @ 6V:||1.3 W|
|Extended motor shaft?:||Y|
|Motor type:||1.6A stall @ 6V (HP 6V)|
Performance at Maximum Efficiency Specifications for Pololu N20 High Power Motor
|Max efficiency @ 6V:||0.38|
|Speed at max efficiency:||490 rpm|
|Torque at max efficiency:||0.15 kg·cm|
|Current at max efficiency:||0.32 A|
|Output power at max efficiency:||0.75 W|
Note: Stalling or overloading gearmotors can greatly decrease their lifetimes and even result in immediate damage. The recommended upper limit for instantaneous torque is 2 kg-cm (25 oz-in); 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 Pololu N20 High Power Motor; a general recommendation for brushed DC motor operation is 25% or less of the stall current.
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.
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.
Husarion has a great article about calculating your ideal motor size here: