Ad Widget

Collapse

Announcement

Collapse
No announcement yet.
X

Some LED How to's..Updated

Collapse
  • Filter
  • Time
  • Show
Clear All
new posts

  • Some LED How to's..Updated

    Below are some tips and formulas needed to
    create LED conversions.

    Related web sites:
    (cheap LEDs, unknown quality, outragous shipping!)
    Hebeild

    (good prices, good shipping, good service)
    Super Bright

    For calculations
    (thanks Jax..)

    First decision, after color, will be power.
    1000 MDC (unit of LED "brightness") = 1 Candle power.
    Most lamps used on motorcycles vary from 2 to 10 CP..
    However you will need to "play" with the number of LEDs
    needed to fit your application. The turn signals I made,
    though I was replacing a 3 CP (3000MDC) bulb were
    made with 6 10KMDC LEDs. (60 CP)
    This was partly due to the "angle" of the LEDs and
    partly due to the subjective nature of comparison.
    (side by side) I also wanted to spread the LEDs out
    so that I avoided the single bulb in the middle effect.
    See my results at the end...

    Next will be the viewable angle.
    For applications where you need "bulb" like performance
    go with a wide angle:
    40 degree


    For applications where you want a spot (plate lights)
    or are useing several all viewed from a narrow angle
    (or are using a colored lens like turn signals)
    you can choose narrow:
    15 degree:


    Once you have these you can find the specs from the
    supplier. Ex:


    A load resistor is needed. An LED has such low resistance that some load needs to be added to the circuit to prevent effecting a short. This resistor allows the LED to run in its optimum rated level so it lasts as long and provides the power it is rated for. Always use the actual max voltage of your application!

    Use this formula in selecting the load resistor.


    Plug in your numbers:


    Order up your LEDs..
    And buy you resistors.
    I suggest at least 1/2 watt resistors for constant use lights.
    Running lights and such.
    1/4 watt will be fine for LEDs seeing intermittant use.
    Brakes, turnsignals. However this is a "weak link"
    Always over build if you can..

    After they arrive test them out.
    Wire a resistor to your 12v+
    Then touch one lead to the resistor and the other to the 12v-
    If the LED does not light switch leads.
    One LED lead will be longer than the other.
    For the life of me I can never remember which one is what..
    Once you have it figured out make a note of it
    For sanity leave the LED on for an hour or so.
    Keep an eye on the temperature of the resistor.
    If it appears to be getting hot you will need a higher wattage unit.

    To create a replacement part for my LP turn signals I
    first removed the bulb holder:

    I then traced the lens to a piece of cardboard.
    I trimmed it to where it fitinto the housing and
    then figured out LED placement.

    Crappy photo I know....
    The two holes at the far end hold the Lexan in place using the housing screws


    Once the templet was complete I laid the template over
    a sheet of Lexan, traced the outline and transfered the LED locations.
    (I used a center punch to go through the card into the lexan.)
    Lexan is available in the glass section of home improvment stores for use
    in replacing window panes, it is sold be the inch so for a project like this
    is very cheap.


    I drilled the holes for the LEDs very close to the actual LED size so that
    they needed to be "pressed" in. This allows me to skip the gluing portion
    Next press in the LEDs so that the + leads are facing the same way.


    To speed things up I twisted each resistor around a drill bit
    about the same size as the LED lead.


    Solder up the resistors.
    One for each LED soldered to the + tail.
    Cover with some shrink tubing..
    I then carefully folded the leads so that I could solder them up
    together. (sorry no pictures of that)
    Solder the resistor wires (free ends) together and this is your
    plus "wire". Solder all the ends of the LEDs together (use some
    extra wire if needed) and this is your ground.
    Attach two wires (or solder in the "salvaged" stock wires.)
    Use a meter to verify the polarity of the incoming voltage and try
    them out!

    Add some RTV to keep out the rain..
    Put the parts together and go..

    My result was this:

    Turn signal, nice brightness and fuller light distribution.

    I did the same for the rear light.
    I traced a shape that would fit inside the shell.
    I mounted it using 1/4 -20 screws
    But they fit into two existing holes in the shell and
    to make it reversable I didn't want to change the shell.

    Running light:

    The next generation will spread them out a bit..

    Stop light:

    Stop light.

    NOTE
    In my design I used single resistors for each LED.
    This way any one resistor burning out means that only a single
    LED goes out not the whole sheebang.. Resistors are pennies a piece.
    And don't add much work..



    NOTE
    Rapid flashing.
    The flasher, or relay that controls the on/off cycle of your turn
    signal is controlled by current. Current flowing through the
    flasher to the turn signals heats it, once heated enough it turns off the
    turn signal, it cools, turning it on etc, etc.
    With LEDs the current is so low the flasher goes into "fault"
    mode. It flashes twice as fast. This is designed to tell you that a
    bulb is out.. (who walks around the car every day to check?)
    Nifty for a car annoying (maybe) if you switch to LEDs..
    So you need to increase the load:
    this gadget does it..


    The resistor simulates the light bulbs.

    But you can wire one yourself (if you want) with a large 5-6 ohm resistor
    and a few diodes.. The big resistors (really big!) can be purchased through
    car stereo suppliers (example:Webber Speakers ) at a very nice price..
    However $15 aint bad. Buying the wrong size resistor could result in a fire.
    There are also special relays that do not have "fault" mode or are adjustable.
    These are more expensive and I have not researched Motorcycle applications.

    Note: HS2020 says that for a few $ you can pick up a 2 prong flasher relay form AutoZone. This will work with low resistance applications.
    Her is the How to for that:
    Questions, answers and posts pertaining to electrical mods and problems

    Some stick with the rapid flashing.. Like pulsing headlights and stop lights they grab attention (maybe) better than standard...
    Last edited by Black_peter; 03-14-2008, 09:34 AM. Reason: spelling

  • #2
    Great piece Peter should be a sticky ...by the way if you want to use only 1 resistor...this site comes in handy..but I like the reason you gave for using one resistor for each one...

    Good judgement comes from experience, and often experience comes from Bad Judgement :smt084
    Help Support Katriders.com via Motorcyclegear.com
    Welcome to KatRiders.com! Click here to Register

    nah nah nah nah nah nah JAX! (special thnx to sexwax)

    Comment


    • #3
      Yeah, I leave that up to the individual...
      I liked playing it safe..
      Plus the my AUX light (converted rear reflector)
      has burned/ lost 3 out of 6 LEDs..
      So I'm glad I went 1 for 1...
      I'll add your link to the main pst Jax.. Thanks

      Comment


      • #4
        AWESOME black_peter, that is what i have been looking for.

        “Programming today is a race between software engineers stirring to build bigger and better idiot-proof programs, and the universe trying to produce bigger and better idiots. So far, the universe is winning.”

        Comment


        • #5
          could you tell us what you did for the flashing aspect of your flashers? heavy duty relays, or just do what you said and that is good?

          “Programming today is a race between software engineers stirring to build bigger and better idiot-proof programs, and the universe trying to produce bigger and better idiots. So far, the universe is winning.”

          Comment


          • #6
            Do you mean to make them flash
            correctly? Nothing.. I:
            a. have not completed my conversion
            b. dont really mind the double flash.
            However I have edited the post with information
            about preventing double flash.

            Comment


            • #7
              yep that is what i meant. thanks black_peter

              “Programming today is a race between software engineers stirring to build bigger and better idiot-proof programs, and the universe trying to produce bigger and better idiots. So far, the universe is winning.”

              Comment


              • #8
                Uh , stickied !
                I am a fluffy lil cuddly lovable bunny , dammit !



                Katrider's rally 2011 - md86

                Comment


                • #9
                  Geez, its stickied

                  Great stuff peter, thanks for all the hard work you put into it for the benefit of everyone!

                  Comment


                  • #10

                    Yeah , I wanted to come back to this one later ! Too much to read this late at night !
                    I am a fluffy lil cuddly lovable bunny , dammit !



                    Katrider's rally 2011 - md86

                    Comment


                    • #11
                      just one more question from me and i leave it alone, how about getting brake light to do or simulate the dual fillament bulb? just have some turn off and all on during braking?

                      “Programming today is a race between software engineers stirring to build bigger and better idiot-proof programs, and the universe trying to produce bigger and better idiots. So far, the universe is winning.”

                      Comment


                      • #12
                        Good one..
                        Ok added pics and text..
                        I appreciate all your input!

                        Comment


                        • #13
                          Originally posted by md86
                          Uh , stickied !
                          The man with the sticky touch!!

                          Comment


                          • #14
                            Didn't read this yet, if you're going to use multiple L.E.D.'s just connect them in series up to 4 or 5 L.E.D.'s depending on there forward voltage, you won't need a resistor (btw assume the operating voltage is 14,7 volts)

                            Comment


                            • #15
                              Now this is a awesome write up B_P!!! well done and very informative. This is the kind of stuff that makes this site better than all the rest IMHO!!
                              TDA Racing/Motorsports
                              1982 Honda CB750 Nighthawk, 1978 Suzuki GS750 1986 Honda CBR600 Hurricane; 1978 Suzuki GS1100E; 1982 Honda CB750F supersport, 1993 Suzuki Katana GSX750FP. 1981 Suzuki GS1100E (heavily Modified) http://katriders.com/vb/showthread.php?t=94258
                              Who knows what is next?
                              Builder of the KOTM Mreedohio september winning chrome project. I consider this one to be one of my bikes also!
                              Please look at this build! http://katriders.com/vb/showthread.php?t=91192

                              Comment

                              Working...
                              X