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Unknown DC motor Specifications

  1. Feb 8, 2008 #1
    Me and another person were rummaging through one of my colleges labs looking for usable parts for my groups product design course. We found this medium size motor that weighed about 2-3 pounds. The problem is that there were no stickers at all that indicated its specifications. There were a few numerical engravings, but without words it was hopeless. We hooked it up to a 12 V power source and it powered up fine. Does anyone know of an easy apparatus we can set up to test for its specifications? Maybe hook it up to an arm and having the arm depress a scale?
  2. jcsd
  3. Feb 9, 2008 #2


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    A dynamometer will help identify some of it's properties.


    What was engraved on the motor? Is it DC or AC?

  4. Feb 10, 2008 #3
    It's a DC motor. I'll post what was engraved on the motor on monday. I put the motor in my schools machine shop for storage, and they're not open on the weekend.... Also I'll check if they have a dynometer that I can check out.
  5. Feb 10, 2008 #4
    just find some tachometer, find its rpm.
    get a multimeter, find its rotor resistance.
    everything can be pretty much calculated from these two
  6. Feb 10, 2008 #5


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    The best way is to be able to apply a varying load on the shaft and then measure the current and voltage. That way you can vary the speed and get a calculation on power at various speeds. That will give you a complete motor curve that you can then use for whatever application you want. A dyno is exactly what this is for. You can try to improvise the loading mechanism though.
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