Help: Understanding LED & Resistors....

[jvirusvirus]

Need help understanding LED's

I want to start a lil project so I can move up to a bigger project but 1st need to understand how and which LEDs and resistors I need.

Basicly the big project(not really but to me yes its big lol)what I want to do is a set of Taillights that are LEDs but don't know which of Leds I need and resistors.

So today I went out and bought a PCBoard and 4 5mm Red LEDs. 2.6volts * 28mA * 10mcd ( Dont really understand what thats telling me). But already burned one LED I connected it to a 9v Infinity Gold Alkaline batter and affraid of doing anything else lol.

A little help please

 

[dorkiedoode]

Need help understanding LED's

I want to start a lil project so I can move up to a bigger project but 1st need to understand how and which LEDs and resistors I need.

Basicly the big project(not really but to me yes its big lol)what I want to do is a set of Taillights that are LEDs but don't know which of Leds I need and resistors.

So today I went out and bought a PCBoard and 4 5mm Red LEDs. 2.6volts * 28mA * 10mcd ( Dont really understand what thats telling me). But already burned one LED I connected it to a 9v Infinity Gold Alkaline batter and affraid of doing anything else lol.

A little help please

read up on this for the basics

http://www.theledlight.com/ledcircuits.html
http://www.gizmology.net/LEDs.htm

you'll need a resistor calc to find the right resistor

http://ledcalc.com/

for your situation
supply voltage 9v
voltage drop across led 2.6
desired LED current 1-28ma for your led (higher the brighter)

it should then output a resistor, for your case would be 270 Ohm for a 28ma single LED on a 9v source. I'm no electrical engineer but you can learn the basics by searching the web about leds.

 

[jvirusvirus]

So lets say i would run 2.6 into a 9v battery i would still need a resistor no matter what? or there times that i would not need the resistors or its always

 

[finch13]

^ what he said. Those LED calculators can be a real life saver.

You need to read up on Ohm's Law and the fundamentals of electricity (volts, amperes (current), and resistance (Ω or Ohms).

 

[jvirusvirus]

will do for now ill put everything from soldering to pcb to leds away lol didnt buy resistors. btw any cool side that have led projects or something like that?

 

[dorkiedoode]

will do for now ill put everything from soldering to pcb to leds away lol didnt buy resistors. btw any cool side that have led projects or something like that?

hidplanet has a thread just for leds! go check it out, they have amazing projects there.

 

[kevinbo03]

+1 for ledcalc.com

 

[RedRyder]

Cool man. But like Finch said, do your research...you can get into some money and problems if you go into it blindly. I think it's cool you're attempting it though.

 

[jvirusvirus]

Lol yea I know doing the research but they just dont write in my language lol

but yea I just bought the tools and a lil pcboard not the led or the resistors though.....

I kind of get it but how would i know how much volts the tail lights get? and what would happen if I dont meet the full power of what it gives what happens to the left over power......

 

[jvirusvirus]

Wow now this site I understand more than others

http://www.kpsec.freeuk.com/components/led.htm

Gets into detail,.....lol or maybe i just need to read it over and over again each day and it just sinks in hahahaha