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Converting frequency to current for an ac generator

  1. Oct 10, 2004 #1
    before anyone has a good laugh at me, I am studying environemental engineering and have to do a course that has some electronics it.

    i have a single phase alternating current (50 Hz) generator that produces 120 volts. I need to calculate the current from this information.

    can anyone help me???

  2. jcsd
  3. Oct 10, 2004 #2
    With nothing but that open circuit, there's no load, therefore no current.

    That would be zero amps.
  4. Sep 23, 2009 #3
    If you had a known load, and knew the resistance of said load you could figure the amp draw by using Ohm's law, E=IR.
  5. Sep 24, 2009 #4


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    Have a look on the side of the generator. There should be a metal plate that gives more information than that.
    If there is a number like 500 VA this will tell you the generator can deliver 4.16 amps (500 VA / 120 V = 4.16 A).

    At the very least, there may be a makers name and model number which you may be able to check on Internet or with some phone calls.

    Failing all that, you can get some 120 volt lamps and start wiring them (safely!) across the generator and then measuring the output voltage. If you are already getting 120 volts out of it, field coil excitation has been supplied internally.
    Measure the total current when the 120 volts drops by, say, 10 % with constant speed drive.

    But testing it yourself should be a last resort. Try to find the maker's data.
  6. Sep 24, 2009 #5


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    Staff: Mentor

    5 year old thread...
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