good place to get super bright led's?

[mattsdragons]

im trying to find a pair of super bright led's that run at about 18v

sort of explosion style yet i can only seem to find 12v or 24v, but no 18v

can anyone help out here?

[typhoon_driver]

Ebay farnell rs components.

Leds can work at any dc voltage within reason. You need to put a resistor in series with the led. There are calculators online which allow you to work out what size resistor you need

[mattsdragons]

i dont want to over volt them, so if they run bright at 18v, they should be fine at 16.8v

[typhoon_driver]

you don't understand LED theory. LEDs don't run at 12v or 24v but at much lower voltages such as 3v. The 12v and 24v surface mount LEDs have a resistor in series inside the casing that reduces the voltage that the LED sees to the 3v value (the remainder sits across the resistor). You can do this far cheaper yourself by buying a bog standard LED and soldering a resistor to it then hooking it up to your battery supply.

Find any LED on rs components, throw the values for the LED into this calculator and bingo, you know what resistor you need for that specific LED.

http://led.linear1.org/1led.wiz

You will be lucky to find a surface mount LED that runs on 18v that doesn't cost you a bomb. Save yourself some cash and make it yourself.

[mattsdragons]

ah, I get that

learn something new every day

[PJ-27]

Nice little calculator, turns out I've been putting far too much resistance on mine.

[terry]

I bought these off ebay last week for under £4 for both of them , they are 12v each so I will wire them in series at 30v with a resistor inline. That led calculator is awsome I will use that quite soon !

[Laser]

That is bright.