PG71 Planetary Gearbox with RS775 Motor and Encoder Question

[Mike Marandola]

Originally Posted by wilderbuchanan

with planetary its around 64 rpm and without its around 5000 rpm

The motor speed is still roughly the same with and without the reduction.

[wilderbuchanan]

i'm confused because the planetary gearbox reductions is 71:1

[cgmv123]

Originally Posted by wilderbuchanan

i'm confused because the planetary gearbox reductions is 71:1

The encoder is on the motor shaft, before the 71:1 reduction happens. The specs for the encoder account for this:

Total Counts per revolution: 497 (7 Counts per motor rotation multiplied by gearbox reduction, 71)

[Mike Marandola]

Originally Posted by wilderbuchanan

i'm confused because the planetary gearbox reductions is 71:1

Yes so the motor inputs about 5,700 revolutions per minute (due to the gearbox efficiency it is more like 5,300 RPM), and after the 3 stage planetary reduction it is about 75 RPM. You can multiply the 75 RPM output speed by the 71:1 reduction and get 5,325 RPM. This is the motor speed even with the reduction with no load.

[Al Skierkiewicz]

As the motor used on this device is a legal motor, the AM-2161, I would expect the part with gearbox and encoder attached would also be legal. It is best to ask this of the Q&A. The AM part AM-2971 simply assembles the three parts into one for a discounted price.

[kitare102]

What are you going to be using the motor for? I can't imagine any applications in which 5000rpm alone is useable.