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Homemade Electric Crank Generator Not Producing Voltage

  1. Mar 16, 2014 #1
    This is a homemade generator I've been trying to make using a hand crank, neodymium magnets and two copper coils. It doesn't work. If anyone has any suggestions on how to configure the magnets or something I am doing wrong your comments will be much appreciated.


    Attached Files:

  2. jcsd
  3. Mar 16, 2014 #2
    You expect to guess how is supposed to work just from that picture?
    Where are the magnets? And what is moving?
  4. Mar 16, 2014 #3


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    Unfortunately, the single view of your generator attached to the OP doesn't provide enough detail of the layout to judge why you are having problems. Several views from different angles would give a clearer picture of its construction.
  5. Mar 16, 2014 #4

    there's magnets on either sides of the wheel and the copper coils at the bottom are connected with more copper wire running beneath the wheel.

    Attached Files:

  6. Mar 16, 2014 #5
    I'm in grade 11 and have next to no knowledge on how this stuff works.
  7. Mar 16, 2014 #6
    It probably is working but the emf you are inducing is very small and you are unable to detect it. To get a big voltage you need to get a large rate of change of flux so you need strong magnets, large coil(s) and fast movement.
    From the picture it seems you have magnets fixed along the axis of the disc. If so the magnetic field is strongest along this axis and is mainly missing the coils.Also the field seems to be at a fixed and fairly long distance from the coils. Arrange it so that the magnets can move closer to the coils and arrange the orientation of the magnets so that their poles can approach and retreat from the coils.
    Try fixing the magnets with the right orientation close to the circumference of the disc.
  8. Mar 16, 2014 #7
    should i put the magnets on the edge of the disc instead of the side maybe... if you look at the first picture they're already incredibly close to the coils
  9. Mar 16, 2014 #8
    Should the magnets be alternating poles from north to south?
  10. Mar 16, 2014 #9


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    I think it would be easier to move the coils. The poles of the magnets should be pointing at the hollow section of your coils like the following:

  11. Mar 16, 2014 #10


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  12. Mar 16, 2014 #11
    should I reorient the coils then so they're perpendicular to how they are now?
  13. Mar 16, 2014 #12
    I would try to stick an iron rod in the copper coils.
  14. Mar 17, 2014 #13
    You should do both: put an iron core in each coil and place them so the axis is horizontal and perpendicular to the plane of the wheel.
    Each magnet will pass through the gap between the two horizontal iron cores.
    Still not the best setup but you may get a measurable voltage.

    In the current position the flux through the coils is very small as the field is mostly parallel to the wire loops .
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