How far can you place a resistor from a LED?

Discussion in 'The Projects Forum' started by Jeeep, Oct 1, 2016.

  1. Jeeep

    Thread Starter New Member

    Jun 16, 2015
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    0
    I want to make an 3x3 LED module that will be about 4 feet from the control board that provides 12v. Do I need to put the resistor on the 3x3 LED circuit board or can I put the resistor on the control board circuit board?
     
  2. MrChips

    Moderator

    Oct 2, 2009
    12,447
    3,363
    It doesn't matter where you put a series resistor. It can go on the +ve leg or the -ve leg, anywhere along the daisy chain.
     
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  3. wayneh

    Expert

    Sep 9, 2010
    12,145
    3,055
    Ditto. It could literally be a mile away and work fine. In that case the resistance of the wire would add to the resistor value, but distance per se is irrelevant.
     
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  4. #12

    Expert

    Nov 30, 2010
    16,321
    6,818
    I wouldn't flinch at the idea of a 100 foot distance. LEDs aren't very smart and they aren't very picky. They don't care about high frequencies or the small amount of inductance in the wires, only resistance. It's hard to imagine a wire that won't carry 10ma or 20 ma for 100 feet, but I could calculate one. Something around 30 gauge.
     
  5. Sensacell

    Well-Known Member

    Jun 19, 2012
    1,132
    267
    As long as it's just LED's- you don't specify what exactly you mean by "3 X 3 module"
     
  6. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    7,392
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    The only consideration I would place is how easy it is to short something out... Place the resistor on the side where it helps lesson the chance of releasing magic smoke.

    That would place the resistors closest to the controller.
     
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