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Homopolar generator

  1. Dec 16, 2011 #1
    I've made a homopolar generator using Al disk, its giving me a output voltage of around 0.1V but shockingly der is no current !! a checked the resistance of the disk its very low as required, i checked for every other problem like : improper contact , smoothness of the disk , symmetry of the field , speed , proximity of the field , insulation of the rotor shaft with the disk , using a thick disk ( around 5 mm ) etc....but there is no current !! can anybody tell me what might have gone wrong....?? homopolar generator is supposed to generate high current at low voltages i want to verify it, can anybody suggest any other way of producing very high current it doesnt matted at what voltage ii just want high current.
  2. jcsd
  3. Dec 16, 2011 #2
    What are you using for a load? How are you measuring the current?
  4. Dec 17, 2011 #3
    The problem is you almost certainly got too much resistance in your circuit. Say you want 10 Amp then since your voltage is 0.1V, R got to be lower than 0.01 Ω which is not easy to do.

    The way I generated a high current in the past is by using a small toroid mains transformer. Thread one or two loops of thick cupper wire through the hole and solder the ends of the wire together. Make sure some of this wire runs outside the transformer. I was able to generate 300 Amps and more. But of course that is ac and not dc. But make sure the primairy coil is not overheating and be careful with the mains voltage.
  5. Dec 18, 2011 #4
    @pantaz : i simply used the multimeter to check the V and I.
  6. Dec 18, 2011 #5
    @ per oni : the resistance of my disk is 1 ohm...should hav atleast shown 0.1 o some amps but it dint show any...should i go fr Cu disk ?.... I even supplied 5amp @12V between the periphery and the centre to see if it atleast rotates but it dint rotate too !
  7. Dec 18, 2011 #6
    Thanks fr replying guys.
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