12v LED tail lights on 24v system

Discussion in 'General Electronics Chat' started by Slimsound, Apr 2, 2014.

  1. Slimsound

    Thread Starter New Member

    Apr 2, 2014
    5
    0
    Hi,

    I am new to this, and so would like some advice.

    I am building a toy car for my son and using a 24volt mobility scooter motor and electronics to power it.

    I have some 12v LED tail lights and some 12v LED headlights to use on it, what do I need to put on line to make it all work?

    I do not know anymore about the LED lights unless someone can tell me how to work it out?

    Do I need a 12v regulator inline on both or just a resistor?

    Thanks in advance for all your help
     
  2. inwo

    Well-Known Member

    Nov 7, 2013
    2,433
    315
    If it was me, and it was a "toy" car. No safety issues. I'd connect them in series across the 24 volts.
     
  3. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,551
    2,374
    My Aurora has DTRL's in series the same way!
    As inwo says and You just need a series resistor for the LED's.
    Max.
    ,
     
  4. Slimsound

    Thread Starter New Member

    Apr 2, 2014
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    Thanks guys, please could you just elaborate on the series resistor? I am not an electronics trained person.
     
  5. MaxHeadRoom

    Expert

    Jul 18, 2013
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    2,374
    Do you have any info on the LED's?
    If they state 12v they may already be conditioned for 12v.
    Max.
     
  6. crutschow

    Expert

    Mar 14, 2008
    13,019
    3,235
    You need to know the current the LEDs take at 12V. Then you add a resistor in series with value R = 12V / Iled.
     
  7. #12

    Expert

    Nov 30, 2010
    16,304
    6,814
    I'm afraid you have wandered off the idea from inwo. Two lights in series need no resistor if they were built for 12 volts each (with their own internal limiting resistor).
     
    ErnieM and inwo like this.
  8. ian field

    Distinguished Member

    Oct 27, 2012
    4,415
    784
    More info on the LEDs would be a good idea.

    If they just have internal resistors then no problem shoving them in series for 24V, if they have internal switch mode regulators - they may not share equally.
     
  9. inwo

    Well-Known Member

    Nov 7, 2013
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    Op called them 12V lights. I'm pretty sure he could wire them to 12V

    It should be a small step to explain a series connection.
     
  10. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,551
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    Most automotive replacement from 12v incandescent to LED's require no resistor.
    Max.
     
  11. Slimsound

    Thread Starter New Member

    Apr 2, 2014
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    0
    Thanks everyone,

    This is the item number for the headlights I bought, 221360513476, it just says 12v but a guessing the will have all the correct resistors in them.
    The tail lights have got three resistors in them each so I thing I will just wire them in series.

    Many thanks

    Sorry for being dumb
     
  12. Ahmad Hassan_1450013929

    New Member

    Dec 13, 2015
    1
    0
    it can be worked by the aid of the concept (Potential Divider )
    and its easy that you can do it by your self
    Just let us first say that have
    Vs (Voltage source) =24 volt
    V led(voltage for the LED you have)=12 v
    Solution..
    you need to introduce 2 resistance and the values for those resistance will be calculated by the following equation:
    V led = Vs*(R1/R1+R2)
    12 = 24*(R1/R1+R2)
    from solving the last equation we will found that R1 = R2
    So technically if add any two resistance in series equal each other (they can 1kohm 7 1Kohm or they can be less )
    and then you connect you LED in Series to any one of them you will have voltage on the resistance equal 12v and it the required voltage ;)

    Note : those resistance will added in series to each other and you lamp will be allocated in parallel to the R that gives you the required voltage drop.
     
  13. #12

    Expert

    Nov 30, 2010
    16,304
    6,814
    The Thread Starter (Slimsound) was last logged in 20 months ago. He/she probably got the lights running, let the children wreck the toy car, and forgot about it. If you only answer recent questions, you are more likely to find an audience that still visits this site.
     
  14. ian field

    Distinguished Member

    Oct 27, 2012
    4,415
    784
    Aliens watch all our communications.
     
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