Need some LED help from some Electrical Geeks!

Tuffguy #2 · 10-26-2007, 11:19 AM

I'm building my own LED arrays from loose LED's. I will use them as blinkers in my eurotail. I'm basically drilling holes and installing the wiring behind the eurotail. I'm pretty good with soldering and basic wiring.

I want to wire them up like this.
X X X X X X X
X X X

Do i have any option but to wire them all up in parallel? The resistance calculator says that series is not possible with only 12.6V supply. Current limiting Resistor calculator for leds

These are the LED's i'm using http://www.customdynamics.com/pdf/5mm%20red%20LED.pdf

Bought from here Motorcycle LED Light Bulbs

These are the inputs i have been using.
12.6V
2.2V drop
30mA
10LED's

I have heard that it is not a good idea to wire up LED's in parallel. LEDs 101
"You can put LEDs in series with only one resistor for the whole series string. Add up the voltages of all the LEDs in the series string. This should not exceed 80 percent of the supply voltage if you want good stability and predictable current consumption. The dropped voltage will then be the supply voltage minus the total voltage of the LEDs in the series string.

Do not put LEDs in parallel with each other. Although this usually works, it is not reliable. LEDs become more conductive as they warm up, which may lead to unstable current distribution through paralleled LEDs. LEDs in parallel need their own individual dropping resistors. Series strings can be paralleled if each string has its own dropping resistor. "

Penny for your thoughts guys. I want them as bright as possible. I don't think i have to worry about the life on them or burning them out, even if i do give them as much juice as they can take. The blinking will allow them to cool between cycles. They'll never me on for very long.

Thanks for any help!!!!!!!!!

Tuffguy #2 · 10-26-2007, 01:03 PM

I think i figured it out. I'll hook them up like this.

R1 X X X X X
R2 X X X X X

The LED manufacturer says that for on and off applications you can max out the current rating on the led's. Good news.
I'll update w/pics next week!