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12v dc small motor, speed control, please help

  1. Feb 27, 2012 #1
    Hi anyone
    I have 7 small 12v dc motors RF-500 TB, max efficiency 0.08 amp max speed 2180 rpm.
    These motors are just holding plastic reflectors of an american police car's roof barlight, they are individually fitted in seperate pods with their own 50 watt bulbs.
    I need 5 pods to spin slower than the other 2, but all to spin alot slower than when the cars 12v supply is added from the battery ( 2180 rpm the reflctor would take off!!!).
    I have asked several parts distributors, They can supply the part but can't tell me what part i need ( Head against brick wall).Any help with what i need and where to get it would be really really appreciated.
    Thanks in advance
  2. jcsd
  3. Feb 27, 2012 #2
    Shouldn't be a terribly difficult project. Since the load on the motors is constant, a simple voltage or current regulator can probably do the trick.

    Some additional info will help:
    Do the motors need to run synchronously (as a set of 5, and/or the "faster" pair), or can the speed vary a small amount between each motor?

    Define "a lot slower" -- 10 rpm, 100 rpm, 1000 rpm?

    Is this a one-time project, a couple of dozen units, or continuing production?

    Are these the motors? http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_238511_-1
  4. Feb 27, 2012 #3

    jim hardy

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    i think you'll want gear-motors.
  5. Feb 28, 2012 #4
    Hi pantaz, Thanks for your reply.
    I would need the 5 to run about 100 rpm and the other 2 about 50 rpm if poss, and no they don't have to be spot on synchronised really.
    This is a one time project for now and a learning curve for me. It is a traffic cop friend of mines american police car that he run's for fun for shows etc.
    The motor in your link looks like the one.
    Thanks for your interest.
  6. Mar 5, 2012 #5
    I'd try servocity.com and look for gearmotors.
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