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Our 20D gearmotors with long-life carbon brushes are now available with extended motor shafts
Last month when we introduced versions of our 20D gearmotors with long-life carbon brushes, we mentioned units with extended motor shafts were in the works. Well, I’m happy to announce that option is now available for both the 12V CB and 6V CB 20D gearmotors, making it possible to use them with encoders like our magnetic encoder kit. The following table shows our full selection of 20D gearmotors, which has now grown to 72 options:
Rated Voltage |
Brush Type | Stall Current @ Rated Voltage |
No-Load Speed @ Rated Voltage |
Approximate Stall Torque @ Rated Voltage |
Single-Shaft (Gearbox Only) |
Dual-Shaft (Gearbox & Motor) |
---|---|---|---|---|---|---|
12 V | long-life carbon (CB) |
1.6 A | 570 RPM | 26 oz-in | 25:1 12V CB | 25:1 12V CB dual shaft |
450 RPM | 33 oz-in | 31:1 12V CB | 31:1 12V CB dual shaft | |||
225 RPM | 58 oz-in | 63:1 12V CB | 63:1 12V CB dual shaft | |||
180 RPM | 75 oz-in | 78:1 12V CB | 78:1 12V CB dual shaft | |||
140 RPM | 85 oz-in | 100:1 12V CB | 100:1 12V CB dual shaft | |||
110 RPM | 110 oz-in | 125:1 12V CB | 125:1 12V CB dual shaft | |||
90 RPM | 130 oz-in | 156:1 12V CB | 156:1 12V CB dual shaft | |||
72 RPM | 160 oz-in | 195:1 12V CB | 195:1 12V CB dual shaft | |||
57 RPM | 200 oz-in | 250:1 12V CB | 250:1 12V CB dual shaft | |||
45 RPM | 250 oz-in | 313:1 12V CB | 313:1 12V CB dual shaft | |||
36 RPM | 290 oz-in | 391:1 12V CB | 391:1 12V CB dual shaft | |||
29 RPM | 350 oz-in | 488:1 12V CB | 488:1 12V CB dual shaft | |||
6 V | long-life carbon (CB) |
2.9 A | 590 RPM | 22 oz-in | 25:1 6V CB | 25:1 6V CB dual shaft |
470 RPM | 28 oz-in | 31:1 6V CB | 31:1 6V CB dual shaft | |||
230 RPM | 54 oz-in | 63:1 6V CB | 63:1 6V CB dual shaft | |||
190 RPM | 62 oz-in | 78:1 6V CB | 78:1 6V CB dual shaft | |||
150 RPM | 72 oz-in | 100:1 6V CB | 100:1 6V CB dual shaft | |||
120 RPM | 87 oz-in | 125:1 6V CB | 125:1 6V CB dual shaft | |||
93 RPM | 110 oz-in | 156:1 6V CB | 156:1 6V CB dual shaft | |||
75 RPM | 130 oz-in | 195:1 6V CB | 195:1 6V CB dual shaft | |||
60 RPM | 170 oz-in | 250:1 6V CB | 250:1 6V CB dual shaft | |||
46 RPM | 220 oz-in | 313:1 6V CB | 313:1 6V CB dual shaft | |||
37 RPM | 260 oz-in | 391:1 6V CB | 391:1 6V CB dual shaft | |||
30 RPM | 310 oz-in | 488:1 6V CB | 488:1 6V CB dual shaft | |||
6 V | precious metal |
2.9 A | 590 RPM | 22 oz-in | 25:1 6V | 25:1 6V dual-shaft |
470 RPM | 28 oz-in | 31:1 6V | 31:1 6V dual-shaft | |||
230 RPM | 54 oz-in | 63:1 6V | 63:1 6V dual-shaft | |||
190 RPM | 62 oz-in | 78:1 6V | 78:1 6V dual-shaft | |||
150 RPM | 72 oz-in | 100:1 6V | 100:1 6V dual-shaft | |||
120 RPM | 87 oz-in | 125:1 6V | 125:1 6V dual-shaft | |||
93 RPM | 110 oz-in | 156:1 6V | 156:1 6V dual-shaft | |||
75 RPM | 130 oz-in | 195:1 6V | 195:1 6V dual-shaft | |||
60 RPM | 170 oz-in | 250:1 6V | 250:1 6V dual-shaft | |||
46 RPM | 220 oz-in | 313:1 6V | 313:1 6V dual-shaft | |||
37 RPM | 260 oz-in | 391:1 6V | 391:1 6V dual-shaft | |||
30 RPM | 310 oz-in | 488:1 6V | 488:1 6V dual-shaft |
Note: Stalling or overloading gearmotors can greatly decrease their lifetimes and even result in immediate damage. In order to avoid damaging the gearbox, we recommend keeping continuously applied loads under 50 oz-in (3.5 kg*cm) for the versions with precious metal brushes and under 70 oz-in (5 kg-cm) for the versions with carbon brushes (the ones with “CB” in the name). Stalls can also result in rapid (potentially on the order of a second) thermal damage to the motor windings and brushes, especially for motors like this that can deliver a lot of power for their size; a general recommendation for brushed DC motors is to limit continuous current to approximately 25% of the stall current.