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White LEDs Driven By Mains

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Im looking, just as a fun project to try, to replace the filament in an incandescent bulb with some white LEDs, to cut power useage and to get white light, rather than warm light.

First of all, Im looking at using **broken link removed** LEDs. How many should I use, per bulb, to get around a 60-80w incandescent equivalent?

For driving the LEDs, Ive found a few circuits:
**broken link removed**
**broken link removed**
**broken link removed**
https://www.electro-tech-online.com/custompdfs/2007/07/20mALEDballast.pdf
(images taken from respective pages - see url).

Which would be the best (and most cost-effective) to use?
 
You'll need a lot of LEDs to replace a 60W light bulb, you'd be much bettef off using a compact fluroscent tube (energy saving light bulb) than LEDs.

The only time LEDs are useful here is when you're replacing a halogen downlighter.
 
Those cheap LEDs are very bright because the beam is focussed into a very narrow angle. My new solar garden lights have an RGB LED that has a good spread of bright light over nearly 180 degrees.
 
wow 130,000mcd! Thats pretty high. If you watch mythbusters, the one myth about the Lights, is if its better to keep them continually on rather than turning them on and off when you leave, because of startup energy useage. It was false, and the kilowatt hours of the LED's were 1kwh, or somthing like that. Point is, that There are pre-made LED lightbulbs.
 
I didnt like the idea of CFL's because they contain mercury, and arent recycled. This wasn't so much to replace every light in the house, and around the world, just something to try and have fun with.
 
in the "incandescent light bulb" thread, i think hero posted a site about cfl's and incandescent light bulbs, i found it very informative!!!!!;) but its not just mercury, its all the electronics to drive the cfl's tube:eek:
 
Compact fluorescent light bulbs are very good but are very inexpensive now.
 
ParkinglotLust, flourescent tubes are recycledable 100%. It's not legally required for home owners or companies that use small quantities of bulbs to recycle them but the facilities do exist. If it bothers you so much get out your local phone book and find a recycler to send your spent bulbs to.
 
Under "Recycling Services", there is one listing, and it's an auto wrecker. Its really a tradeoff - burn a lot of coal to produce a lot of energy to run the incandescent lights, or burn a small amount of coal to produce a bit of energy to run the CFL's, but leach mercury into the ground in the landfills.
 
Contact Norfolk Waste Services. If they don't accept mercury lamps, I'm sure they'll tell you who will.

I used whitepages.com, and plugged in the word waste and N0E 1Y0.
 
I saw some new White LEDs the other day on ABC 'new inventers' program, they are special technology, they can run directly from the mains AC supply, ie no power supply or rectifiers are needed. (no power supply losses)
There is very little info on them yet as they are not in production as far as I Know.
One would assume they are connected in series to match the input voltage & unlike current LEDs they can tolerate reverse voltage or maybe 2 LED crystals per LED.
I am just rattling here as I know nothing yet of the technology used.

see **broken link removed**
Episode 23 July 11, 2007 (clik on the 'Browse all inventions' button to find episode)

In LED lambs we build, we use parallel groups of series strings to optimise efficiency / minimise dark areas due to failed LEDs.
One problem with series strings of LEDs for HV applications is when 1 LED goes open the whole string is out (just look at the traffic lights, some have whole areas dark). one way around this is to fit zener diodes across smaller numbers of series LED groups, this way only a few are dark if 1 is open.

The mains AC has significant voltage transients that will damage LEDs if not managed with some form of protection. Lightning would be a common source for overvoltage damage depending where you live.
 
LED lightning isn't as efficient as florescent lighting.
 
The current generation of mass-produced white LEDs is not as effective. It's about twice as good as a light bulb of the same wattage, but the energy savings aren't enough to overcome the major drawback of being expensive.

As soon as those ultra efficient LED's are both available and cheap let me know.

By the way, I'm also well aware I make a large number of typo's and I don't bother spell and grammer checking all my posts, waste of time.
 
I have some of those 130,000 MCD LEDs! They're pretty neat. Wanted to make a unique flashlight but haven't gotten around to it.

Anyhow- to power off the mains, you really do need a current mode switching power supply. The SuperTex HV9910. Tolerates even 220V inputs and has a fairly low part count. There's another SuperTex part for this too that has power factor correction but it requires a lot more external parts.

As mentioned these LEDs are quite directional, sometimes you want that but usually not for room lighting. Right now I'm really digging the Luxeon Rebel line, it's incredibly cheap and easy to work with for the kind of light they put out. They've got a 160 deg spread. They're a teeny tiny point source so without some sort of frosted housing (which regrettably reduces output quite a bit) it'll totally blind you.

http://www.futurecb.com/Store/InCategoryFullTextFilteringSearch.aspx?Keywords=lxml&SearchType=Keywords&CategoryName=41301000000&ManufacturerName=LUMILEDS+LIGHTING
 
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On the various high efficiency LEDs.

Philips LumiLEDs Rebel:
**broken link removed**

Seoul P4:
**broken link removed**

CREE XR-E:
**broken link removed**
 
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