LED Back lights!

I've been to an electronics shop and they've gave me a different resistor and said it should work so going to try that first then if that fails i'l try your way :rolleyes:
 
I found out where i was going wrong with the wiring and also found this site to help me...
http://www.projectx.com/Kits/LEDNotes/

I've decided to wire the led's in parallel groups of 18, 19, and 11 and using one resistor for each group. the site tells you exactly what resistor to use. The reason my resistors was getting so hot was because i was using 1/4 watt resistors instead of 10 watt for brakes and 5 for sidelights :eek:

Il try and get the right ones tomorrow and will let you's know what happens fingers crossed :wall:
 
Whoops....were you using a resistor on each LED then ??

What is the forward voltage of the leds you have ?? Most are around 2v to 3v so how can you use 19 of them on 12v ??

You want to work it out on the max voltage when the car is running (14v ???), divide that by the Fv of the LED and use that number of leds in series with a resistor (ignore the poin whatever). Just run a load of parallel circuits with that number of LEDs in each one..

leds5kb.jpg



When I looked into this I was gonna use all the LEDs for side and brake. I was looking at wiring a few std diodes into the power wire before the leds. When they are on sidelights the power travels through those first to drop the brightness. When the brakes are applied the power comes in after the std diodes so they run at full brightness...
 
Im still running them in parallel but instead of 91 for the tailgate lamps each and 101 for the car body lamps im splitting it up into sections of 18 19 and 11 and using 1 resistor for each 18. The problem was that i didn't have enough current to run them all causing the resistors to get far to hot hopefully this way will fix it. I can't run them in series because i've wired them all in now and that would mean buying another 400 led's and starting all over again.
The forward voltage of the resistors is 2v and 20ma so im using resistors to run them at 10ma for side lights and 20ma for brake lights hopefully the 10ma should be bright enough
 
can't you use a 12v transformer

so use a transformer to cut the voltage down and then use a relay so when u brake it triggers the relay and runs the transformer ? may be easier
 
The supply voltage MUST be greater then the sum of the forward voltage of your leds in a series circuit..

So for 2v LEDs you can only run 6 from 12v. See my pic above, you need to run lots of parallel circuits with 6 in each.

Actually it's better to keep to a max of 80% of the total voltage, so 80% of say 14v is 11.2v. That means a max of 5 leds per series circuit...

Darren, I mentioned regulating the voltage earlier...
 
markbuts3 said:
The supply voltage MUST be greater then the sum of the forward voltage of your leds in a series circuit..

So for 2v LEDs you can only run 6 from 12v. See my pic above, you need to run lots of parallel circuits with 6 in each.

Actually it's better to keep to a max of 80% of the total voltage, so 80% of say 14v is 11.2v. That means a max of 5 leds per series circuit...

Darren, I mentioned regulating the voltage earlier...
Click to expand...

sorry i never seen it i was thinking of running all the leds on a 3 volt rail not running the leds on a parallel circuit
 
That looks really nice. I opted for LED bulbs as it's easier, and then discovered the bulb mounts in at an angle... :roll:
 
Oz. said:
That looks really nice. I opted for LED bulbs as it's easier, and then discovered the bulb mounts in at an angle... :roll:
Click to expand...

I used led bulbs at first and something must have happened in the bulbs cos they turned my high level brake light into a stop and tail light :confused:

I've had the lenses off about 4 times on each light and the last time i had to take it off i hadn't even fitted it properly, just taped it on so i could use my car whilst doing it. I took it off by just pulling with it only resting on the top and its smashed straight down the centre and up the indicator AHHHHHH STRESS!!!!!!!!!!! :wall:

I've finally got all my led lights done i'l post up a pic tomorrow when i can get a good one :D
 
Finished pics :D .....

The camera doesn't show them as good as they really are
 

Attachments

  • picture021.jpg
    picture021.jpg
    155.1 KB · Views: 145
  • picture022.jpg
    picture022.jpg
    254.7 KB · Views: 127
I think the side lights are too bright but im just going to let the police decide lol if they pull me then they are and if they dont then they're not :lol:
 
As long as the lights are even, get brighter when you brake, and are not insanely bright (ie majorly offesnive to the eyes) then I think you'll be fine...
 
I'l try and get some pics of in the dark but haven't yet because i've been trying to make the sidelight less bright. I've wired 1 single dash bulb in series with every lamp and its done the trick, all sorted :D
 
You must log in or register to reply here.
Back
Top Bottom