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Selecting the correct diode

  1. Jun 15, 2010 #1
    I need to know what diode to use for the following spec:

    I need to use this for my motorcycle. I have 2 xenon headlamps working on my bike but 1 lamp lits up for low beam and the other for high beam, now I need to light up both which means I've got to use a diode. Need to know which is the best diode for this purpose?

    Battery output: 12v, 4A
    Headlight output: 12v, 35w
    Xenon Ballast input voltage, 9-16v
  2. jcsd
  3. Jun 15, 2010 #2
    Post a schematic. If you have a single ballast and two arc lamps you can't run them both.
  4. Jun 16, 2010 #3
    I have two ballast individually for both the lamps. But when i turn on the low beam one bulb lights up n for the high beam the other bulbs lights up. I need both the bulbs to light up when i turn on High beam. Th e output voltage for the bulb is 12v, 35w.

    Attached Files:

    • 1.bmp
      File size:
      255.5 KB
  5. Jun 16, 2010 #4


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    [PLAIN]http://dl.dropbox.com/u/4222062/lamps.PNG [Broken]

    The diode would be carrying about 3 amps, but should be rated for about 6 amps. It would need to be the type you can mount on a heatsink. Insulate the heat sink from ground.
    Last edited by a moderator: May 4, 2017
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