Quick question about wiring LED lights?

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01-14-2007, 09:03 PM

#21

son209

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You don't have to solder the LEDs onto a board. Most LEDs are 3volts and have two legs on them. The longer leg is the positive side. Take four or five of the LEDs and series them together and you won't need to put a resistor in line.

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01-14-2007, 09:38 PM

#22

reggie 00

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Quote:

Originally Posted by Kyle95sr5

Kevin you just confused the crap out of me! Those last pictures just totally lost me. So with the first pictures, the smaller guage wires are just jumpers from where you had to continue either the postivie or negative path or what? So I was wrong, you have to connect the cathode and anode? Can you please use like...lamens terms. I get some of it but big words confuse me

Man are you trying to drag some old info out of my old mind or what

The simplest way is to start by drawing it out on paper. Each LED has a + and a - .
Each of these terminals need to get to the respective "battery wire", weather it be in parallel w/ a resistor, or series /w no resistor. All the PCB is is a way to interconnect them. What you have seen is just a wired version. The big pics will be burned to basically have the wires inside, much cleaner.

It has been so long since i had to design this (16yrs) I am catching the flow, and slowly clearing the cob webs. You seem to be on the right track don't get frustrated just yet. might be easier if someone just drew it out on paper

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01-14-2007, 09:39 PM

#23

Keggo

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Quote:

Originally Posted by Kyle95sr5

It just goes like this:

...+LED-.....+LED-.....+LED-.....+LED-... The resistor can go in front of the first led, or after the last one. Basically, just hook solder a jumper wire from the negative of one led to the positive of the next... soldering them in line with eachother. Don't use the method of not using a resistor and using a bunch of leds to pad the voltage down... that is a horrible way of doing it and puts a lot of stress on the first led in the string.

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01-15-2007, 05:27 AM

#24

midiwall

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Quote:

Originally Posted by Keggo

Don't use the method of not using a resistor and using a bunch of leds to pad the voltage down... that is a horrible way of doing it and puts a lot of stress on the first led in the string.

Agreed, but you'll still have voltage drop from each of the LEDs in the string. Getting enough current to the LED farthest from the resistor will still put a lot of load on the first LED.

I'm "okay" with 2, maybe 3 LEDs in series, but that's it. Anything else should be done "the right way" which is to run them in parallel on common anode (or cathode) and a resistor on each LED:

Code:

+ -----+-----+-----+-----+
       |     |     |     |
       R1    R2    R3    R4
       |     |     |     |
       D1    D2    D3    D4
       |     |     |     |
       |     |     |     |
- -----+-----+-----+-----+