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Insulation affecting the current carrying capacity

  1. Jul 12, 2007 #1
    HI.... i wanted to do an extensive project on electricity and i thought of something. When i take a normal conduucting wire with a plastic insulation on it, and connect it in a circuit, does the insulation affect the current carrying capacity of the wire? i mean to say in one case if i apply a potential to it and suppose with the help of an ammeter find that lets say 10 amps of current is flowing through it....and in another case if i take the same conducting wire but this time without the insulation coating, will more current flow? like does the insulating material affect the current conducting capacity of the wire? i know we might get a shock if there was no insulation....but is this phenomenon possible? will more current flow? and if it will then how can i design an elaborate practical experiment...i mean for my project i need to take experimental readings and collect the numeric data....so how do i design the circuit?
  2. jcsd
  3. Jul 12, 2007 #2


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    Science Advisor
    Homework Helper

    Assuming that your are talking about DC current, or AC of low enough frequency that we don't have to worry about skin effects or waveguide modes.
    The insulator does have an effect in that it increases the temperature of the wire and so increases it's resistance (which then further increases the temperature). When designing high power electrical installations you have to take into account the insulation and ductwork's cooling effects to specify how big the wires must be.
  4. Jul 12, 2007 #3
    The research experiment....

    thanx a lot for clearing my doubt but is there any other reason, maybe any othe minute reason....thats why i have heard that in huge transformers there are fuse lage boxes or something like that in which conductors are kept without insulation so that electricity can flow in large amounts....and the whole thing is covered by an insulated box so that nothin touches the interiors.....is it true? thanks a lot....but now i need to design an elaborate experiment to prove this by observing and taking numerical data...how do i do this? how will the circuit diagram be? please reply soon....
  5. Jul 12, 2007 #4


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    Do you understand the basics of electricity? It would be best if you understood a bit more about voltage, current and resistance before you spend much time crafting experiments. Do you have a technical library near you? If so, please check out the book, "The Art of Electronics" by Horowitz and Hill. I think you will get a lot of value out of it, and the first chapter or two will explain enough of the basics that you will be ready to spend some quality time experimenting.

    Last edited by a moderator: Apr 22, 2017
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