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Resistor question

  1. Dec 8, 2006 #1
    hello, im new here.. so please excuse my..um. n00bishness
    im sorry if this under the wrong area, i doint know which area of physics it might be under, i just remember reading about resistors back in HS physics...which was years ago..

    I'm currently building a shed lighting system through the use of luxeon leds.

    after some series led resistor calculations, I need a 15 ohm, 1.8 watt capable resistor. as far as I know there are none manufactured under the specs. I was wondering, is there a way to pair two 15 ohm 1/2 watt resistors to achieve this requirement?

    for reference:
    Led: RX1W luxeon lambertian die x 4
    vf: 3.4 [typ] @ 350 ma.
    Vin: 12V @ variable current

    Thanks in advance
    Last edited: Dec 8, 2006
  2. jcsd
  3. Dec 8, 2006 #2


    User Avatar

    two won't do it (not enough power and wrong resistance) but four will do it. two in series and the two series pairs in parallel. (or the other way around.) you'll get 15 ohms and 2 watts.
  4. Dec 9, 2006 #3
    Thanks, since the resistors normally come packaged in 6 packs.

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