Power LED Residential Lighting

[Ubergeek63]

I never said UL was a law so please don't put words in my mouth. It sounds like you have an axe to grind about UL. I think they provide a decent service - what would have in their place - nothing?

You actually did refer to UL as though it was an authority.

The statement of compliance to an international standard similar CE (I forget what the standards are that CE refers to and if I did I would be remembering the medical devices standards since that is what I design to) to from a reputable standards lab as opposed to that of a self serving bigoted money grubber like UL.

Note that when assigning blame for fires and such, the lack of UL certification has a lot of weight. I'm pretty sure there are similar bodies (governmental or not) in most countries. Whether they are "deceptions" or not they get to say if a product meets safety criteria.

Actually that is the deception. They do not "get to say", they BS the buyers and the public into thinking they "get to say". UL is NOT a requirement-ANY testing would hold water over no testing in court. The ONLY thing the UL is is a TEST LAB... NOTHING MORE! The little UL symbol is nothing more than a trade make that they force companies to pay protection money for. Protection money in the form of over priced tests ... As I said, they charge $5000 just to shuffle papers about.

Show me a CE and I will consider it. A VDE and you have something to brag about. UL is garbage, and while garbage is better than nothing, give me a 220V safety rated failure on 110V before you give me a UL passing grade any day!

UL is nothing more than another ego maniacal monopoly. They force companies that want to sell in the US to pay $5-20K to THEM on substandard tests that are already exceeded by the international ones that were already payed for.

Also, I know a number of experimenters that are using much more powerful LEDs than that. I don't think it is beyond them.

The power level is not the issue, what is at issue is that many power LEDs require that the thermal pad be epoxied to a heat sink and isolated from the circuit. Most experimenters that are using much more powerful LEDs are using stars, ie they are premounted.

If they can not get the thermal contact the LEDs will burn themselves out.

I have mounted ones that can be handled, worked with stars, have assembly equipment at work that can handle the silicone lens parts, and will likely have luxeon rebels in production in a year or so.

 

[transistance]

Hi Wilbe,

It hurts 100 times a second !

on1aag.

Can the human eye distinguish that high frequency of a flickering?

The general idea seems to call this a "silly" idea. I would like to use CFL's since I was able to find some below 1.5 inch thickness, and that they are very feasible in long term.

Here is my question though, the cope of the project includes a dimmer. Is this possible with an array of CFL's?

Note: The effect I'm trying to achieve here is the look of a self-illuminated ceiling. (aka Ghetto EL Panel Ceiling)

Thanks for all the input!

 

[nickelflippr]

Led Edge lit acrylic panels. Sandblasted or chemically etched (one side) tempered glass make great diffusers, and would be less dust prone than the acrylic. With the cost of dimmable fluorescent ballasts, leds could be back in the picture? Get some 12V rgb strips and controller from your favorite Hong Kong dealer and have all kinds of fun.

 

[transistance]

Led Edge lit acrylic panels. Sandblasted or chemically etched (one side) tempered glass make great diffusers, and would be less dust prone than the acrylic. With the cost of dimmable fluorescent ballasts, leds could be back in the picture? Get some 12V rgb strips and controller from your favorite Hong Kong dealer and have all kinds of fun.

I'm trying to get a face lit effect that can light up the room, not an edge lit. Kind of like the back light in LCD screens.

 

[Hero999]

You can get CFLs that can be used with standard lamp dimmers.

You can get dimmable ballasts.

I've heard that it's even possible to make your own flurocent lamp dimmer without even doing any soldering. I'll post a schematic and hopefully a link if I can find it.

Another more simple option could be to just turn more lamps on to increase the brightness and turn more off to dim.

 

[Willbe]

Above 24 Hz flicker is not detectible due to persistence of vision. . .?

I thought UL is a well-known and independent testing lab, and therefore has more credibility because of that independence (and supposed competence).
But, this may also apply
**broken link removed**)

Here's Wiki's take on these people-
Underwriters Laboratories - Wikipedia, the free encyclopedia

 

[transistance]

Some googling has revealed to me that there are specially manufactured CFL bulbs to work with dimmers. The problem is most of these bulbs have a warning to be used in an upright position and not to be enclosed - otherwise a fire hazard.

Any products that anyone knows of? Dimmable, does not have to be upright, can be enclosed CFL's, preferred less bulky - that's going to be a challenge...

 

[audioguru]

I think a movie has 24 frames per second but each frame is shown twice to reduce the flickering to 48Hz.
My LED Christmas tree lights flicker at 60Hz and it is obvious.

Interlaced old CRT TV screens had each line flickering at 30Hz and it was very obvious.

 

[Willbe]

I think a movie has 24 frames per second but each frame is shown twice to reduce the flickering to 48Hz.
My LED Christmas tree lights flicker at 60Hz and it is obvious.

Interlaced old CRT TV screens had each line flickering at 30Hz and it was very obvious.

Persistence of vision - Wikipedia, the free encyclopedia

Seems like 85 Hz might be a minimum.

 

[Nigel Goodwin]

I think a movie has 24 frames per second but each frame is shown twice to reduce the flickering to 48Hz.
My LED Christmas tree lights flicker at 60Hz and it is obvious.

Interlaced old CRT TV screens had each line flickering at 30Hz and it was very obvious.

European TV's have 25Hz interlaced frame, hardly anyone can see any flickering, at 30Hz in America it's even less visible - it's certainly not 'obvious'.

If you are one of the incredibly tiny percentage of the population who can see it, you obviously find it annoying - and you should buy an inferior picture 100Hz (120Hz for you) set.

 

[audioguru]

The interlace produces flickering when some straight thin lines are in only half of the interlace. They blink at 30Hz here and at 25Hz in Europe.

 

[Insider]

I have been working on LED Lights for more than an year now and I have found them easy, cool, and power saving as compared to CFL. There are problems with diffusing the light but the newer 170 deg LEDS are good with a 18,000 mcd rating you can get a good room light for lesser overall ownership cost. The technology is New but it is the 5th Generation Lighting and has come to stay. I am sure using Cree Led's can give you a better idea about what I am saying.
I have designed Flood Lights, Billboard Lights, Room Lights, DownLights, Pool Lights and I am quite comfortable with my clients who appreciate my hard work and dedication.

Kinetics Automation
Pakistan
fahimbaig2@gmail.com

 

[Hero999]

Here's a circuit for a fluroscent lamp dimmer. I haven't tried it so I don't know if it works.

The power factor correction capacitor mustn't be after the dimmer or it will blow the TRIAC.

You also need as switch before the circuit to turn off the transformer or it will remain on wasting energy and shortening the life of the tubes.

 

[Ubergeek63]

I have been working on LED Lights for more than an year now and I have found them easy, cool, and power saving as compared to CFL. There are problems with diffusing the light but the newer 170 deg LEDS are good with a 18,000 mcd rating you can get a good room light for lesser overall ownership cost. The technology is New but it is the 5th Generation Lighting and has come to stay. I am sure using Cree Led's can give you a better idea about what I am saying.
I have designed Flood Lights, Billboard Lights, Room Lights, DownLights, Pool Lights and I am quite comfortable with my clients who appreciate my hard work and dedication.

Kinetics Automation
Pakistan
fahimbaig2@gmail.com

Perhaps I am missing something here.... this is news how?

 

[Hero999]

He's just spamming.

It depends on the application, generally for as a high powered diffuse light source CFLs are more efficient and LEDs are more efficient for direct light sources especially where a certain colour is required and of course, they have a longer life time and reach full brightness immediately.

 

[Ubergeek63]

Can the human eye distinguish that high frequency of a flickering?

Not a chance unless it is beating with something else.

Note: The effect I'm trying to achieve here is the look of a self-illuminated ceiling. (aka Ghetto EL Panel Ceiling)

Not an easy thing to do... hanging torches or even medieval style one for effect ... lighting the room with light reflected off the ceiling works great.

150Lm is enough to read by that way if the ceiling is white. Modulating reds and ambers would give you a flickering flame effect on the ceiling... not practical and to late for this year's antics

 

[transistance]

I am going to try to implement a huge array (about 60) of 1W diffused white LED's behind some kind of diffusing semi-transparent screen. Also I will implement some kind of a rectifier circuit.

Once I get the initial design (test the brightness from different screens with a smaller array), I will put up my ideas here for some feedback and design of the rectifier.

 

[Kitrax]

Osram huh? I've played with them before, but I ended up preferring the Phillips Luxeon Star LED's... These suckers come on a "star" PCB with a built in heat spreader. Their brightest Star is the Endor Rebel which pumps out 540 lumens @700mA. They have lenses that fit over the star too...the only problem is, for an LED and a lens, it's going to cost you over $40 each. The company also sells drivers for their LEDs soyou don't have to worry about current sourcing.

These LEDs are way better than CCFLs in every way except initial price.

 

[transistance]

Osram huh? I've played with them before, but I ended up preferring the Phillips Luxeon Star LED's... These suckers come on a "star" PCB with a built in heat spreader. Their brightest Star is the Endor Rebel which pumps out 540 lumens @700mA. They have lenses that fit over the star too...the only problem is, for an LED and a lens, it's going to cost you over $40 each. The company also sells drivers for their LEDs soyou don't have to worry about current sourcing.

These LEDs are way better than CCFLs in every way except initial price.

That's an exceptionally huge price to pay. Another reason for a DIY project is to bring the price below or around the same level as commercially available products (at least in my case).

 

[Ubergeek63]

That's an exceptionally huge price to pay. Another reason for a DIY project is to bring the price below or around the same level as commercially available products (at least in my case).

The $40 is the DIY unit price!

Deal Extreme's entry level mounted LED is **broken link removed**