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How to connect 100,3mm White LED 6000 mcd, to 110 Volts?

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I need to connect arround 100, 3 mm white LEDs in series to 110V ( household electricity). Can just connect them all in series and hook them up to the power source or do i have to add resistors? is there any website that could give me the circuit diagrams?
I will appreciate everyones help

You can connect a number of them with a series resistor and a bridge rectifier to the 120 volt line.

The number you can connect, and the value of the resistor depend on the specifications on the LEDs. You do have specs?

Usually you have a typical Vf, a max Vf, and a nominal If. With a lot in series we can probably work with the typical. Assume this is 3 volts, and If is 50 mA. You can recalculate for different numbers.

Now we need to pick a voltage across the resistor, this serves to limit the current, as Vf changes a lot with temperature, and without a limiting resistor, you can burn out all of the LEDs. I'll pick 20 volts as the drop on the resistor. That leaves 100 volts for the diodes, and at 3 volts each, you can only put 33 in series. So you need 3 strings of 33 each, each string with it's own resistor. But they can share the same rectifier.

Resistor would be: 20v/50ma = 400 ohms
Power dissipation is 20v*50ma = 1 watt, use a 2 watt resistor. You can use 8 – 50 ohm 1/4 watt resistors in series.

Bridge, use 4 1N4004 rectifiers in a bridge configuration.

Add a 1/2 amp fuse. But while you are experimenting, I'd add a 100mA fuse to each string.

PS, you do know that 120 VAC or DC can be lethal, and cause fires?

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White iPhone 4 Delay Echoes Past Apple Issues

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Apple announced July 23 that its white iPhone 4 would be unavailable until later this year. Apple's aesthetic demands and complex production techniques have led to issues in the past.
White LED Light Kit (Warm White, Cool White) - Under Cabinet, Bar, Behind TV, Accent Lighting

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The Rise of Residential LED Lighting and What You Should Know

Almost everyone today knows what an LED light is in the most general sense, but few are aware of how fast it is set to become the main source of general lighting in both homes and businesses. Everyone from the Department of Energy to environmental advocates are pushing the pace of LED general lighting development because of the dramatic savings in energy associated with their use, and the fact that LEDs use no environmentally harmful substances like some older energy-saving bulbs (i.e. compact fluorescents which contain mercury).

Although light emitting diodes have been around since the 1960’s, their use up until several years ago was confined to such things as indicator lights in electronic devices, traffic signals and instrument panels. It wasn’t until the invention of the white LED (in the late 1990’s) that people began to take a closer look at their ability to replace incandescent lighting in homes or businesses. Being a technology that uses a semiconductor to produce light means that the output and efficiency of LED lights is improving at a rapid pace; today’s LED replacements can achieve a life span of 50,000 hours while consuming 80% less energy than a standard incandescent bulb. LEDs that produce a warm white light were invented by accident in 2005 but will allow a person to replace their incandescent bulbs with a similar color light to what they’re used to. An additional benefit of LED lighting is that only a very small amount of UV or IR radiation is emitted, making it highly useful for locations where valuable art is hung on the wall or fading may be an issue.

The current market is full of LED replacement bulbs and lighting solutions, but it is also buyer beware. There is a lot of junk on the market today that if bought and tried will surely disappoint you. Well made LED replacement bulbs are still pricey and the cheap products on the market today, a lot of them being sold through big box stores, will not last nor produce or sustain a bright enough light. On a side note, LED bulbs (LEDs don’t really need to be a bulb!) don’t usually “burn out,” instead their usable life is measured by a certain percentage decrease in brightness. The Department of Energy is using considerable resources to promote LED lighting (also called SSL, or Solid State Lighting) and just recently announced the Energy Star specifications for residential LED usage. That means in the near future you will have some assurance as a buyer that the product you are purchasing really will live up to your expectations.

In the meantime, it is important to buy your LED lighting from a trustworthy source with good customer service in case of any problems you might experience with this new technology. Companies that have established their credibility by working closely with, and traveling to, the factories making the LED lighting they carry are a good place to start your shopping. Look for the offer of a money-back guarantee if you are unsure of what you are buying and how it’s going to work. Now is the time to start using LED lighting, but be sure to shop wisely and you will save yourself both time and money in the long run.

 

About the Author

Sean Coppom is an employee at Polar-Ray, a Boulder, CO web-based business specializing in LED lighting solutions for residential and commercial customers.