Electronics How do I know how much current a wire can take?

Discussion in 'Modding' started by tribaloverkill, 9 Jun 2005.

  1. tribaloverkill

    tribaloverkill Who needs sleep,... bah.

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    I have to hook up two 120mm 105CFM YS-TECH fans to one set of wires. I believe the wire I have is either 22 or 20 guage. Will this size wire be able to power these two fans without a problem? The wire is rated up to 300v but what about current? I don't know to much about this kinda of stuff. Thanks.
     
    tribaloverkill, 9 Jun 2005
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  2. shotgunefx

    shotgunefx What's a Dremel?

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    You might find this chart handy.

    How much do the fans draw?
     
    Last edited: 9 Jun 2005
    shotgunefx, 9 Jun 2005
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  3. Ghlargh

    Ghlargh What's a Dremel?

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    if the wire is shorter than a meter, it should get warm to the touch before you notice any large problems with voltage drops.

    If it starts smoking, that is a good sign that it's too thin.
     
    Ghlargh, 9 Jun 2005
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  4. tribaloverkill

    tribaloverkill Who needs sleep,... bah.

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    Well,... it's a 12v fan and it mentions 5.52w on the back so the current should be .46A? I know if I run them paralleled the current over the wire would be doubled. That wouldnt work anyways because there wouldnt be enough voltage to get them going anyways. SoI would have to run them in a series. This would mean that only .46A would be running through the line total right? If so then 22 or 20 guage should be fine. right?
     
    tribaloverkill, 9 Jun 2005
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  5. cpemma

    cpemma Ecky thump

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    No, cos the fans would only get 6V each, current would be about half the rated 0.46A. The fans need to be in parallel, each then get 12V and the source supply wires deliver 0.92A, 0.46A to each fan. 20G will run them fine.
    Code:
    Series:

12V-------Fan 1-------Fan 2------0V


Parallel:

12V------+--------+
         |        |
       Fan 1    Fan 2 
         |        |
0V-------+--------+
     
    cpemma, 9 Jun 2005
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  6. Wolfe

    Wolfe What's a Dremel?

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    when you smell burning insulation, you know you've gone too far.
     
    Wolfe, 9 Jun 2005
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  7. tribaloverkill

    tribaloverkill Who needs sleep,... bah.

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    Thats right I forgot. It's been awhile since I've played my some LEDs. So in series the volts is devided between fans and the current is .46. In parallel the volts is 12 and the current is doubled in the power lines. Gotcha. Thanks. I'll be needing your site soon mr cpemma. I need a voltage/ current regulating circut for my LCD screen and a variable one for the fans. Thanks again.
     
    tribaloverkill, 10 Jun 2005
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  8. cpemma

    cpemma Ecky thump

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    No, the current's halved as well. A fan on 6V doesn't draw as much current as the same fan on 12V, and because it's a series circuit current is the same all the way round it.
     
    cpemma, 10 Jun 2005
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