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LEDs power question(newb)

  1. Jul 12, 2007 #1
    first of all HELLO evry1,i am new here!!
    I have a motorcycle and I wanna do something special to it so I decided on putting some LEDs on.
    I buyed 20 pre-wired LEDs (http://cgi.ebay.com/20x-Blue-LED-La...8QQihZ005QQcategoryZ66948QQrdZ1QQcmdZViewItem)
    The only problem now is the power,can someone tell me what kind of battery(ies) I need?
  2. jcsd
  3. Jul 12, 2007 #2
    According to the specs, the LEDs have an input voltage of 9 to 14 volts.

    This leads to many possibilities. Do you want to tap the power from your motor's battery, or provide a separate power source?
  4. Jul 13, 2007 #3
    I want a separate source because I have enough room
  5. Jul 13, 2007 #4
    Well, firstly, is there any power/current/voltage rating of the LEDs that you have bought? You need to know that before you can provide a power source.

    the consumption of LEDs are generally very low, so battery replacement would not be very often. (If you're wondering about power consumption too)
  6. Jul 13, 2007 #5
    Thank you very much for the information Tw15t3r !!
    The 20 LEDs are 12V DC with Forward Voltage (V) 3.2 ~ 3.8 (I don`t really know what that means :redface:)
    I think that the motor battery will do the job
  7. Jul 13, 2007 #6
    Hmm, yes, it should work. Guess ur problem is solved then.

    For the record, 3.2-3.8V forward, would mean that, connected the right way (LEDs connected the wrong way won't light, and if too high a voltage the wrong way... boom.) it can tolerate 3.2-3.8V. So I'm probably guessing about 4 LEDs are in series with each other, so since each can take 3.2-3.8V, total, ends up with around 9-14V. Hope it helps.
  8. Jul 13, 2007 #7
    Thank you very much for all!!!
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