Need CIM Motor Specifications

[Andy Baker]

Originally Posted by expiredzbyte

CIM Motor:

Stall Torque: 2.22 N-m … 19.472 lbs/inch
Stall Current: 107 A
RPM: 5,500
Free Current: 2.3 A
Peak Power: 321 W

This is what we are being told, from the motor's specifications. This is what we've all be designing to over the past 2 years since we started getting these motors in 2002.

But...

I don't believe them. Seriously. This thing seems to spin at more rpm than 5,500 at free speed. I'd bet a Coke that the free speed is more like 6,000 rpm (Mt. Dew sucks - there, I said it). Last year, there were some people who tested this motor and showed different numbers than what it is rated, but I can't remember who did it nor what their results were.

We put one on a gearbox a few weeks ago and the output speed of the gearbox seemed higher than the calculated speed if there were no efficiency losses. While I have gotten better at designing gearboxes over the past couple of years, I seriously doubt if I have found a way to increase the power of these motors through super-efficient gear reduction.

If someone has the tools to test this thing, will you post your results?

Andy B.