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Minimum gauge wire to connect low-current LEDs? — Parallax Forums

Minimum gauge wire to connect low-current LEDs?

LittleTykeLittleTyke Posts: 34
edited 2009-03-04 00:25 in General Discussion
Maplins in the UK do a light-duty flexible wire, specification: 10/0.1mm copper, nominal conductor area: 0.0785mm2

Would this be adequate gauge from a 74HC759 or 74LS240 pin to a low-current LED up to 1.8 metres distant? I have a number of such wires to run in a very small space so the thickness of the wire is crucial.

Comments

  • skylightskylight Posts: 1,915
    edited 2009-03-03 12:47
    If its the one from the light equipment cable section its states 1000v working voltage at 0.5 A (500W max)·, distance is <2 metres with the load being very small so volt drops not an issue with BS7671 regs and it being ELV.
  • dandreaedandreae Posts: 1,375
    edited 2009-03-03 15:04
    This thread is being moved to the Sandbox.

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    Dave Andreae

    Parallax Tech Support·
  • PhilldapillPhilldapill Posts: 1,283
    edited 2009-03-03 19:24
    LittleTyke, using the resistivity formula, I'm getting a total resistance of about 0.4 ohms for your wire at 1.8m long. If you are pulling 50mA, the voltage drop is about 0.02V - which should be negligible.

    To find the resistnace of a material, take the resisitivity value(1.7 x 10^-8 for copper), multiply that by the length, and divide by the cross sectional area. The area and length should be in meters^2 and meters.
  • Carl HayesCarl Hayes Posts: 841
    edited 2009-03-04 00:25
    Translating all the above, YES -- it will work perfectly well and be quite safe.

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    · -- Carl, nn5i@arrl.net
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