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SOmewhat simple LED wiring

  1. Aug 2, 2008 #1
    Hi. New here. I'm not necessarily a newb at wiring I've used solder before and have wired up other simple wiring diagrams. I'm hoping someone can help me with a task I'm looking at doing. I'd like to wire up a set of LED taillights. 48 red led's in the brake circuit and about 24 in the turn signal circuit. The brake light will require a SPDT relay to switch from being illuminated and braking. I have a diagram but have no idea what kind of resistor values I will need. It's a 12V system. Any help is much appreciated
    These are the specs on the red LED's I have:

    Material: InGaN
    Emitting Colour: Red
    Lens Type: Water clear
    Reverse Voltage: 5.0 V
    DC Forward Voltage: Typical: 1.9 V Max: 2.3 V
    Wave Length: 625-635nm
    Luminous Intensity: Typ: 15,000 mcd
    DC Forward Current: 20mA
    Viewing Angle: 20±5degree
    Lead Soldering Temp: 260oC for 5 seconds
    Intensely Bright

    This is the wiring diagram I intend to use:
  2. jcsd
  3. Aug 6, 2008 #2
    The problem that you are going to have with someone responding to your request, is that you are messing with a safety system on a vehicle. There is not only a liability issues, but also a moral issues. If you want to do the math yourself it is very straight forward. What you are trying to do is all covered in ohms law. You can use the resistors as current limiting devices, so you only have to worry about the voltage drop across the resistors you are going to be designing with. Also another thing to concider is the safety where your circuit will be located. Will it get wet? Will it get dirty? Will it be able to withstand the physical jarring of normal vehicle travel?
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