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Error tolerance in coil design (number of turns)

  1. Mar 20, 2012 #1
    I am designing a coil which will have 2100 turns of 30AWG wire.
    The bobbin diameter is 1.045" and the length is 1.28"

    From my calculations I will use about 8,420 inches of wire.
    I tried an online calc but they did not take into account that the wire I am using has a heavy insulation so it's diamter is about .0115".

    As we know things is the real world are usually somewhat different.

    My question is how much of an error tolerance I should expect in terms of wire length for the 2100 turns? And should I expect to use more or less wire than calculated?

    Any help/suggestions would be greatly appreciated.
  2. jcsd
  3. Mar 21, 2012 #2
    Layer wound or random wound?
    If layer what is layer insulation?
    If random wound, depends on winder. Assume maybe 60% fill?
  4. Mar 21, 2012 #3
    Is this a math exercise? Like how many balls can you fit in a can?!!!

    Just get extra wire and wind it, point is you want to have extra to make sure you have enough!!!
  5. Mar 21, 2012 #4


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    Science Advisor

    You could go back to the online calculator and tell it you have 26 gauge wire. This has a diameter of 0.0159 inches which is close enough to your wire with its thick insulation.

    But it is an imprecise business and difficult to calculate exactly, so you do need to have some spare wire.

    The main problem may be how many turns you can fit on your bobbin.
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