[Richard Wallace]

Originally Posted by Schmitty!

I measured the no-load speed and current of several of the motors we received in the 2006 KOP with an optical tachometer and Fluke DMM. I got the following results:
Small CIM #1 +12.00V: 5370 RPM 2.06Amps
Small CIM #1 -12.00V: 5412 RPM 2.00Amps

Small CIM #2 +12.00V: 5209 RPM 2.00Amps
Small CIM #2 -12.00V: 5374 RPM 2.13Amps

Large CIM #1 +12.00V: 2665 RPM 0.700Amps
Large CIM #1 -12.00V: 2738 RPM 0.790Amps

Large CIM #2 +12.00V: 2752 RPM 0.802Amps
Large CIM #2 -12.00V: 2686 RPM 0.690Amps

Fisher-Price #1 (without gearbox) +12.00V: 16224 RPM 1.06Amps
Fisher-Price #1 (without gearbox) -12.00V: 16579 RPM 1.03Amps

I am planning on grabbing the remaining no-load measurements tonight. So far the measurements I've taken fall in line with what I expected based on the datasheet values. I'm very happy to see that the Fisher-Price motor is a 12V motor!

Does anybody have a dynomometer test stand that can be used to capture the torque data? I can set up a test at stall to capture the stalled torque constant, but from previous experience it is more accurate to capture the torque constant while the motor is spinning under a known load. I don't have access to a dyno at my current job.

I have a Magtrol HD-715 dynamometer and Sorenson DCS 20-150 switchmode power supply in my day-job lab. I did a quick 12V test of the large CIM motor this morning. With the motor coupled to the dyno and no load (apart from dyno friction) applied the speed was 2710 RPM and the current was 1.5 Ampere. Peak efficiency was about 85% at 43 oz-in, 2470 RPM drawing 7.7 Ampere. Peak shaft power was about 218 Watts at 193 oz-in, 1530 RPM drawing 33.5 Ampere. The maximum steady load that I applied was 283 oz-in, 750 RPM drawing 51 Ampere. I did take the loading up to about 350 oz-in momentarily without stalling the motor, but did not leave it there long enough to record steady data.