Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Portable Generator Remake Help

  1. Dec 19, 2012 #1
    Hello everyone, I am new to this forum and this is my first post. I have an old generator that I have been working on. It is a rotating-armature 3-phase generator with a commutator. I tore everything off of the shaft because there was a short somewhere and I planned to remake the generator myself for a little learning experience.

    The stator electromagnet seemed fine when I plugged it into a battery, so I left them alone. Then I drilled 12 holes in the shaft. I did this so there would be six "poles" to wrap wire around. I would then use the six poles to make three separate windings.

    Anyways, I got the bolts glued into the holes at the perfect amount of length, they are very close to touching the electromagnet, but they never actually do. Just for a test run, I took a 60ft roll of 16awg wire and wrapped it around two bolts approximately 50-100 turns. I didn't count. I rigged up some slip rings and soldered the connections there, used a multimeter and it fluctuated between 0.01 to 0.14V. This sounds very wrong because the original wire that was wound was 12awg and I would say it had approximately the same amount of turns.

    I found a transformer in the circuit and tested it out. I put a 120VAC connection on it in series with a light bulb(so it wouldn't short circuit) and it returned 0.07V with the leads one way, I then reversed the leads on the voltmeter and it showed 0.01-0.03V.

    Anyways, that's a little background on my story. Here are some minor questions I have now. I would appreciate if you guys could help out.

    Why do I get different voltages when I switch the leads with the voltmeter?
    Wouldn't that much of a jump in voltage greatly decrease the current?
    Whenever I diagnosed it in the beginning, the commutator outputted 1V and it is supposed to be 20V. I know transformers wont work with DC, so how does that jump up?

    Do most generators use a transformer to get to 120VAC or 240VAC? I would think they would just wind the amount of turns needed.
     
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted



Similar Discussions: Portable Generator Remake Help
Loading...