Electric Bike Generator Issues

Discussion in 'Electric Bicycles' started by jjmoen, May 19, 2011.

  1. jjmoen

    jjmoen New Member


    I have a 1/8 hp motor that we were hoping to use as a generator. It is supposed to turn at 810 rpm when supplied with 230 V and 2.7 A. When we spun it at 810 rpm, we only got 4 V though. Are we doing something wrong or is the motor defective? Or does the motor not respond the same when going from mechanical to electrical as it does in reverse?

    Also, the shaft can move about 1/2" into and out of the motor. Is this a problem?


  2. loquin

    loquin Active Member

    230V... Is this AC (from a wall outlet) that you're applying to the motor? (and, you're not in the U.S., I assume...) AC motors do not provide an output when being turned externally. (unless they are altered internally to convert them into an alternator.)

    If it's a DC motor, then they can act as a generator when spun, if they are permanent magnet motors. Stepper motors can also act as a generator when spun.

    As far as the shaft runout - that is not a good sign...
  3. HseLoMein

    HseLoMein Member

    IF you can supply a voltage to one of the coils on an AC motor, you will get a voltage. The reason this happens, is becuase an AC motor is built similarly to a Alternator, there are two coils that spin, unlike a DC motor that 1 coil and a magnent. Get a permanent magnent motor, it will make a great generator