Light up with LEDs today!

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LED DIY Help Page

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Disclaimer: The following information is to be used as a guide, as it involves electronics
Please be aware of the dangers involved as it only takes a few miliamps to hurt someone
Please have a read of the following website to read more about electrical safety:

Shortcuts: Introduction | LED Info | Wiring Info | Resistors Info | Lumens Calculator


What is LED ?

It stands for Light Emitting Diode (LED) which is a semiconductor diode that emits light when an electric current is driven in the forward direction of the diode. LED technology is becoming one of the major innovation of the lighting industry. There are multiple uses of LED lighting. Traditionally, LEDs were used in indicators, number-display panels, lab & testing instruments. As LED technology continues to strive, we now use LEDs in traffic lighting, signage & advertisement lighting, decrotive lighting and also in some automotive applications. Street lamps and house lighting is currently being developed.

This guide will assist you with LED project ideas and also tools which are required. Happy Reading.

Tools Required:

dotSoldering Iron
For non-demanding purposes, an electric powered (20-40W) soldering iron easly purchased from Dick Smith for under $10. If mobility becomes an issue or you want to work around the car without having to work your way around the power cable, you might want to get a butane gas soldering iron and look for the Iroda brand.

I recommend a general purpose electronics grade flux-cored 60/40 (tin/lead) solder. There are non-lead containing solder but sometimes don't flow as well as the leaded ones do.

(***Precaution: Lead vapour is hazadous to your health, do your soldering work in a well ventilated environment, or even better, buy yourself a small fan and blow the fumes elsewhere)

As LEDs generally don't use much current and is generally a low voltage/low current circuit, wire selection isn't normally an issue. However, its always better to check the current running through the circuit. For normal operations, a cable with >1Amps rating is in most cases sufficient.

A good bench is always good, preferably something not conductive.

dotPower Source
A good idea is to have a good 12V DC power source ready for testing your LEDs. Some options: Old car battery, a charger with a 12VDC output or a small 12VDC battery.

A good tool to test the voltage/current/resistors - a must for a electronics project!

Now we've got everything covered, what's left is the components and this is what our store provides you with. Whether it be LEDs, Resistors or PC Boards. Keep reading this guide and you'll learn how to wire up a LED circuit.


Project ideas:

There are a whole variety of things you can do with LEDs, Here are just some ideas!

dotCar Lighting:
Map/Dome/Boot/Licence Plate Lights, Turn
Indicators, Tail Lights or just General Illumination

dotRC Vehicles:
From the headlights to the tail lights or anywhere you want them to light up

dotFish Tank:
For mood light or general illumination (Precaution: Water)

Can use LEDs to light up your PC Case

General Information about LEDs
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So What exactly is a Light Emitting Diode (LED)?

dota semiconductor device that has the ability to emit light
dotable to deliver low power consumption compared with traditional incandescent bulbs
dotlong-life when used appropriately (>50,000 hours)
dotalways use resistors or a LED driver when powering LEDs
dotnever look directly at an operating LED as it may damage your vision

dotcomes in variety of viewing angles and intensity which are used in various applications

So what is LED Brightness or MCD or Lumens?

LEDs are commonly described in terms of their millicandellas or MCD for short. MCD is a measure of brightness at the light source. However that's not the whole story. LEDs are also come in a variety of viewing angles or in other words how wide the light is projected. This is what determines the Luminous flux of the LED which is measured in Lumens (Lm). Lumens is the measure of light that actually falls on a plane or surface.

Below is a MCD to Lumens calculator providing that you know the viewing angle.

MCD - Lumens Calculator

millicandellas(mcd) Half Angle* (degrees)
Total Light Output

*Half Angle = Viewing Angles / 2

So when to use what type of LED? Below is a quick overview of what type of application different LEDs are used.

Wide angle (100-180 degrees) - for basic illumination and backlight where a wide viewing area is required

Narrow Angle (20-40 degrees) - for indicators or strobe lights or where a narrow but intense beam is required
Here's a comparison between wide and narrow angle LEDs

Wide Angle 180 Degrees
230mcd @ 180 Deg.

Narrow Angle 20 Degrees
8000mcd @ 20 Deg.

wide angle blue narrow angle

Now you can work out using the calculator which LED has the greater Luminous Flux or in other words, the actualy light that falls on a sufrace. (Answer: Wide angle: 1.45 lumens, Narrow angle: 0.76 lumens)

So depending on your application, you may want to use a different type of LEDs. If you have any queries regarding which LEDs to choose, do not hesitate to send me an email us .

How to wire a LED circuit?
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For basic soldering techniques please visit Link or PDF

  • On a LED, the long leg is usually the positive terminal
  • resistors should be wired on the positive side of the power source
    Here's an schematic example:

LED Wiring Diagram

  • 12V(positive terminal) ----Resistor------LED------LED------LED-----(negative terminal)

Resistors Reference Table
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  • The following is the recommended resistor usage for LED circuits using 12V @ 20mA
  • Resistors are 1/4 watt unless otherwise indicated
  • It is NOT recommended to wire single LEDs unless you use a 1/2 watt or greater resistor (or else the resistor will overheat and burn)

For 3.3 volts LEDs (blue, white, green etc.)
1 LED - 470 ohms (1/2 watt)
2 LEDs - 270 ohms
3 LEDs - 120 ohms
4 or more LEDs - Use multiple arrays of LEDs

For 2.0 volts LEDs (red, amber etc.)

1 LED - 560 ohms (1/2 watt)
2 LEDs - 470 ohms (1/2 watt)
3 LEDs - 330 ohms
4 LEDs - 220 ohms
5 LEDs - 100 ohms
6 or more LEDs - Use multiple arrays of LEDs
  • Note: Some of our LEDs have rated currect between 20-100mA,
    which means they can run at a higher current if appropiate resistors are used

    Thanks for taking the time to read our LED Help Guide.
    We hope this has helped you in some way.

    Should you have any questions do not hesitate to contact us !
    or you can chat with me on MSN -

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