# High Quality Chinese Generic LED's



## jashhash (Nov 3, 2011)

Contrary to public opinion on this forum, China is beginning to produce much higher quality LED's than most people would like to think. I have been working in LED street lighting for 2 years now and can tell you that I have evaluated Chinese LED's to perform up to 130 lm/w at 350 mah. I have also run our current Chinese Generic LED model for 6000hrs (thats 9 months straight) and have tested them to depreciate only 3%. Yesterday I was just chatting with another Chinese vendor who sells a 1w LED for 55 cents and the efficiency is astounding as shown here. I will be receiving the samples shortly to verify whether or not these test results are accurate. Note that this led has a VF of 9.6v which means it contains 3 dies.


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## blasterman (Nov 3, 2011)

It's a bit of semantics when we refer to 'Chinese LED's' given it's near impossible to find a product not made in Asia. However, there is a distinction between LEDs designed and produced by Western Companies vs LEDs produced by Asian manufacturers who are simply flipping production lines at night or sharing semiconductor recipes in the black market.

Over in a salt water forum I submitted some 10watt Chinese LEDs so a member could test them with a spectrometer, and the results compared to base Cree's were pretty made for the Chinese tech. Compared to XT-Es the popular SEMI based Chinese LED that's rampant on Ebay is maybe half as efficient. If you'd like to challenge those conclusions be aware you are on the wrong side of the facts.

Given the fact that the market for cheap emitters is based on price and not performance there's no need for the Chinese to 'up' their technology. Cree, Bridgelux, Luxeon , etc., are in a race to build the most efficient emitters, or they lose business. The Chinese can sit on old tech and ride out Luxeon III based technology because they are selling at a cost per lumen perspective and they can post specs with fudged numbers few people can read. The mere fact I've pointed out so many times that a Bridgelux is not only cheaper but is actually brighter than the more expensive 10watt Ebay emitter proves this out.

Last, and perhaps most important, when I buy a Cree, Rebel, or Bridgelux emitter I've learned I can trust the specs. With the Chinese stuff you often have to reverse engineer what they are doing to figure it out and then consult a Ouija board. Not sure what the Chinese character set is for 'CRI' but it's obviously missing from Mandarin. 

The fact you feel the need to confirm the numbers for the fixture you posted kinda proves something. If the product were based on Cree, Rebel, Bridgelux, etc., and you had the bin codes an engineer could probably nail the performance within ~5% just doing the numbers. Seems you don't even trust your own product although it's not saying it has bad performance.


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## jashhash (Nov 3, 2011)

Your right there is a lot of Chinese crap out there. It does require that a person sift through all the crap and do an enormous amount of testing. But all of the American companies at some point were subject to scrutiny of independent testers on this forum and we know that CREE, Lumileds, and the other more reputable companies do fudge their performance specs. I'm not claiming that there is a single Chinese LED out there which can go head to head against the XML. Name brand LED's will always dominate the high end market. However the fact that I can buy 7 LEDs from china for the cost of a single XML (I can get XML wholesale for $3.76) means I have more buying power. Now we all know that LED's become more efficient when driven at lower driving currents. So if I take 5 of the Chinese LED's and drive them at 1/2 watt I can get more light output and higher efficiency than a single XML all for a lower upfront cost. Once again I don't think this will have any impact on where we buy flashlight LED's here on the forum because we are all enthusiasts and will always buy the best quality at whatever cost. The general lighting market however such as street lighting and residential lighting is where Chinese generics will have a great advantage.


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## evilc66 (Nov 4, 2011)

jashhash said:


> The general lighting market however such as street lighting and residential lighting is where Chinese generics will have a great advantage.



True, but it's also where they might destroy the reputation and consumer opinion of LEDs, because of the general lack-luster color performance from Chinese LEDs. When talking about direct color LEDs, there isn't a problem. China/Asia has yet to figure out how to make a good looking white LED. CRI (The Ra average at least) is not a good representation of color performance.


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## SemiMan (Nov 5, 2011)

evilc66 said:


> True, but it's also where they might destroy the reputation and consumer opinion of LEDs, because of the general lack-luster color performance from Chinese LEDs. When talking about direct color LEDs, there isn't a problem. China/Asia has yet to figure out how to make a good looking white LED. CRI (The Ra average at least) is not a good representation of color performance.



Second on this. Streetlight is NOT where Chinese LEDs will be used. To be cost effective, these do need to last 20 years. The Chinese have even scaled back their own streetlight projects as their domestic suppliers are unable to make reliable streetlights with good optics. Never mind getting an LED right, they have trouble creating proper optics.


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## slebans (Nov 5, 2011)

evilc66 said:


> True, but it's also where they might destroy the reputation and consumer opinion of LEDs, because of the general lack-luster color performance from Chinese LEDs. When talking about direct color LEDs, there isn't a problem. China/Asia has yet to figure out how to make a good looking white LED. CRI (The Ra average at least) is not a good representation of color performance.



The problem with *sweeping generalizations* is that they are often wrong. I do not agree with including all of Asia in regards to the inability to produce quality White LEDs.

China has a publicly stated goal to dominate the world market for LEDs. They have committed close to $20 Billion US dollars to R&D and local production. They have secured partnerships with many of the world's leading LED producers to build production on Chinese soil. Yes, it will take them many years to reach the same level of quality that currently exists at the pinnacle of the industry - but they will get there. I certainly would not bet against them.

Stephen Lebans


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## slebans (Nov 5, 2011)

SemiMan said:


> Second on this. Streetlight is NOT where Chinese LEDs will be used. To be cost effective, these do need to last 20 years. The Chinese have even scaled back their own streetlight projects as their domestic suppliers are unable to make reliable streetlights with good optics. Never mind getting an LED right, they have trouble creating proper optics.



From what I have read, China did not so much as scale back their Streetlight program but they basically stopped it completely. Local suppliers were not solely using Chinese produced LEDs - therefore quality was not the only issue - but a lack of enforceable standards contributed to a failure of the program. Now that standards are being put in place I believe we will see a resurgence of the program. And one thing about Chinese Government standards - once they are in place you do not want to face the consequences of avoidance.

Stephen Lebans


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## Lynx_Arc (Nov 5, 2011)

jashhash said:


> Your right there is a lot of Chinese crap out there. It does require that a person sift through all the crap and do an enormous amount of testing. But all of the American companies at some point were subject to scrutiny of independent testers on this forum and we know that CREE, Lumileds, and the other more reputable companies do fudge their performance specs. I'm not claiming that there is a single Chinese LED out there which can go head to head against the XML. Name brand LED's will always dominate the high end market. However the fact that I can buy 7 LEDs from china for the cost of a single XML (I can get XML wholesale for $3.76) means I have more buying power. Now we all know that LED's become more efficient when driven at lower driving currents. So if I take 5 of the Chinese LED's and drive them at 1/2 watt I can get more light output and higher efficiency than a single XML all for a lower upfront cost. Once again I don't think this will have any impact on where we buy flashlight LED's here on the forum because we are all enthusiasts and will always buy the best quality at whatever cost. The general lighting market however such as street lighting and residential lighting is where Chinese generics will have a great advantage.


The problem with using 5 LEDs to replace one LED is obvious when people buy a single XM-L light instead of a 3x XP-G light. It may be cheaper and more efficient to use LEDs but the space used and labor and design costs for having to use 5x the LEDs may not save you anything. I think first off they need to come up with a standard LED socket system or two for high powered LEDs so they can create a fixture and easily swap in another module 5 years from now when the LEDs go bad in it. Ease of replacement does help if you have to replace a little more often. I think 20 years is unrealistic for longevity of daily used LED lighting. Efficiency is a top consideration but durability is equally important thing. chinese generic LEDs have not proven themselves to be consistent on any front yet and the track record of chinese LED companies is such that people that want to invest millions in commercial lighting are cautious to bet on an unproven track record. 
I don't trust chinese LEDs by their word only I would trust an american source to test them over the hype that the chinese companies have been guilty of when it comes to their products. 
Essentially the chinese have a record of making a good product and when it starts selling then they have other factories making the same product trying to profit more.. quality suffers but those selling them source them wherever is cheapest such you end up with an inferior product so guaranteed performance is a huge issue.


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## blasterman (Nov 6, 2011)

> but they will get there. I certainly would not bet against them.



As long as I'm having to explain half a dozen times a week in this forum and reefing forums to somebody that a $12 10-watt SEMI based Chinese LED with a rated range of 400-800 lumens bought on Ebay *is not* a better deal than a $8.50 800 lumen Bridgelux, then indeed the Asian 
semi-conductor industry is going to win. Mostly because American consumers are too retarded to make intelligent choices based on junior high school science. Game over - inability to penetrate skull.

This has nothing to do with bigotry or flag waving, but the basic ability for educated consumers to read simple specifications. If LED #1 is more efficient, brighter, costs less and is posting reliable specs from Western company than LED #2, LED # 2 is not a better deal because it's posted on Ebay.

Frankly I don't care where the product is made. If anything, I'm more frustrated at American shell companies that design a product in the U.S., then have it made entirely in Asia at 1,000% cost mark-ups then cry foul when competing Asian companies produce clones at a fraction the price. I otherwise see no reason why the Chinese shouldn't be capable of producing LED's within a negligible performance envelope of Cree or Luxeon, but the reality is they have dumped so much junk on the market it's nearly impossible to sift through the junk and their record for protecting intellectual patents isn't exactly stellar.


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## blasterman (Nov 6, 2011)

> China/Asia has yet to figure out how to make a good looking white LED[/quopte]
> 
> If we look at the spectral graphs redfish made on Nano-Reef mainstream Chinese blue efficiency is about half an XTE. If you can't make a blue with decent efficiency, you won't make a white efficiently.


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## idleprocess (Nov 7, 2011)

blasterman said:


> As long as I'm having to explain half a dozen times a week in this forum and reefing forums to somebody that a $12 10-watt SEMI based Chinese LED with a rated range of 400-800 lumens bought on Ebay *is not* a better deal than a $8.50 800 lumen Bridgelux, then indeed the Asian
> semi-conductor industry is going to win. Mostly because American consumers are too retarded to make intelligent choices based on junior high school science. Game over - inability to penetrate skull.


The inability for some to source components from sources _other_ than E-bay, DealXtremei, etc - not known for their timely, reliable delivery of top-notch quality products - astounds me. Sure, spin wheel, maybe you'll get something amazing for nickels on the dollar - maybe you'll buy a single $1 lotto ticket and hit it big, too - but the odds are against you.

Pay a fair price for something reputable from a supplier with a return address and some history and the odds improve immensely.


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## Lynx_Arc (Nov 7, 2011)

idleprocess said:


> The inability for some to source components from sources _other_ than E-bay, DealXtremei, etc - not known for their timely, reliable delivery of top-notch quality products - astounds me. Sure, spin wheel, maybe you'll get something amazing for nickels on the dollar - maybe you'll buy a single $1 lotto ticket and hit it big, too - but the odds are against you.
> 
> Pay a fair price for something reputable from a supplier with a return address and some history and the odds improve immensely.


Exactly, chinese manufacturers don't have brand loyalty when it comes to LEDs. Generics are a crap shoot and places such as DX will switch suppliers for various reasons sometimes to get better products and sometimes to get better profits. Until quality and consistency is proven long term investment in chinese LEDs is a gamble not worth taking if you cannot afford to lose bad. I have heard of many issues with LED traffic lights and signals for just that reason. Cities cannot afford to invest in flaky products on a large scale.


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## jashhash (Nov 7, 2011)

Alright I have received the samples from China today and have run them all through integrating sphere tests. The 55 cents LED, the one I'm most interested produces 116 LM/W when driven at 1 watt, At 1/2 watt the LED efficiency is about 131 LM/W. What that means is that it takes 4 of these LEDs to equal the light output and efficiency of a T5 bin XML which costs me $3.76 wholesale. I bargained with the Chinese supplier who agreed to a lower the cost to $0.52 each which means $2.08 to replace an XML. I will be running two sample groups, one group will be running at the maximum rated output of 1w and the other group will be running 50% hotter than recommended for 3 weeks straight at which point I will test for depreciation. 
I have tested another LED model that cost $1.50 each that contains what appears to be a 1.5mm X 1.5mm die produced by Nichia. I have tested this LED to produce 135 LM/W when driven at 1 watt, and have tested it to produce 124 lm/w when driven at 1.5 watts. This $1.50 LED is performing better and cost less than a R-5 bin XPG. 

My prediction is that within 2 years China will catch up to CREE in terms of quality and performance. After 5 years I expect Chinese LED's to surpass CREE in terms of quality and performance.



> As long as I'm having to explain half a dozen times a week in this forum and reefing forums to somebody that a $12 10-watt SEMI based Chinese LED with a rated range of 400-800 lumens bought on Ebay *is not* a better deal than a $8.50 800 lumen Bridgelux, then indeed the Asian semi-conductor industry is going to win.



I'm not referring to the 10 watt arrays which really do suck. To equal the output of the Bridgelux array I would need 6 of these LED's which would cost $3.12 (maybe around $6.00 retal not $12 like your saying. 



> The problem with using 5 LEDs to replace one LED is obvious when people buy a single XM-L light instead of a 3x XP-G light. It may be cheaper and more efficient to use LEDs but the space used and labor and design costs for having to use 5x the LEDs may not save you anything.



While its true for the flashlight world that using extra dies increase cost of components such as optics, in the street lighting world this is not the case. Additional LED dies doesn't increase production cost that much simply because manufacturing is done with extremely fast CNC pick and place machines. The time difference in manufacturing an LED board with 1 LED's as apposed to 5 LED's is only a 3 second increase in production time each. 



> Streetlight is NOT where Chinese LEDs will be used. To be cost effective, these do need to last 20 years.


Last year the company I work for has sold 1.2 million dollars worth of LED street lights which use 100% Chinese manufactured LEDs. So far there have been no warranty claims on any of the fixtures sold. While all LED companies claim that their LEDs will last 60,000hrs there are very few lighting companies willing to offer warranties past 10 years. A warranty that long is way too much liability for the manufacturer. The average LED street light caries a 5 year warranty.


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## idleprocess (Nov 8, 2011)

jashhash said:


> Alright I have received the samples from China today and have run them all through integrating sphere tests. The 55 cents LED, the one I'm most interested produces 116 LM/W when driven at 1 watt, At 1/2 watt the LED efficiency is about 131 LM/W. What that means is that it takes 4 of these LEDs to equal the light output and efficiency of a T5 bin XML which costs me $3.76 wholesale. I bargained with the Chinese supplier who agreed to a lower the cost to $0.52 each which means $2.08 to replace an XML. I will be running two sample groups, one group will be running at the maximum rated output of 1w and the other group will be running 50% hotter than recommended for 3 weeks straight at which point I will test for depreciation.


Hope they didn't put their thumb on the scale and send you top-shelf product that they won't (or can't) supply when it comes time to buy in quantity. Might want to ask someone else that's been buying the same stuff in volume and test a random lot out of their inventory.



> My prediction is that within 2 years China will catch up to CREE in terms of quality and performance. After 5 years I expect Chinese LED's to surpass CREE in terms of quality and performance.


Given the recent history of Chinese industry and their apparent disregard for intellectual property, one wonders if they're actually performing the research on their own, or simply copying the recipe from companies that locate production there.



> While its true for the flashlight world that using extra dies increase cost of components such as optics, in the street lighting world this is not the case. Additional LED dies doesn't increase production cost that much simply because manufacturing is done with extremely fast CNC pick and place machines. The time difference in manufacturing an LED board with 1 LED's as apposed to 5 LED's is only a 3 second increase in production time each.


Parallelism has its price relative to high-performance serial design. Additional machine time isn't free - especially on high-speed automated equipment - you'll need to account for placing 4 more components _(in an earlier paragraph it was 3?)_ when it comes time to price out the new assembly. You also need a bit more thermal management, larger PCB's, additional optics, driver changes, etc.



> Last year the company I work for has sold 1.2 million dollars worth of LED street lights which use 100% Chinese manufactured LEDs. So far there have been no warranty claims on any of the fixtures sold. While all LED companies claim that their LEDs will last 60,000hrs there are very few lighting companies willing to offer warranties past 10 years. A warranty that long is way too much liability for the manufacturer. The average LED street light caries a 5 year warranty.


I'd say that while one year without warranty claims is a good start, it's not yet conclusive. A microswitch rated for 10,000,000 operations needs to be designed to hit something like 50,000,000 before the manufacturer can reduce failures at the 10M mark to a negligible rate.

I'm not familiar with the business model for street lights, but if your product is appreciably worse than what it preceded, it may well bode ill for your company's long-term prospects. Save for the bulbs in HPS/MH designs (and far less frequently the ballast), streetlights seem to be low-maintenance affairs that last for decades. LED designs are typically touted as having 25k-50k lifespans, which means ~5 - 10 years of operation at 12 hours/day.


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## jtr1962 (Nov 8, 2011)

jashhash said:


> While all LED companies claim that their LEDs will last 60,000hrs there are very few lighting companies willing to offer warranties past 10 years. A warranty that long is way too much liability for the manufacturer. The average LED street light caries a 5 year warranty.


It's normal business practice to only warranty a product for a fraction of the time it will generally last in service. If LED streetlights are typically warrantied for 5 years, then most will make it past the 25 year mark with no issues. If they don't, the company will be out of business. 25 years isn't unrealistic for LEDs running about 13-14 hours a day on average. That's about 125,000 hours. Data from both Cree and SSC suggest under proper conditions ( low junction temperatures, fairly low current density ) white LEDs can make it past 300,000 hours with 70% lumen maintenance. That equates to roughly 60 years of streetlight duty. The ultimate design goal for LED streetlights will probably be to have them last as long as the physical fixture they're put in. This can be anywhere from 50 to 200 years, depending upon the materials and design. The same design goal would effectively make exterior building lighting last as long as the building ( design life of most skyscrapers is on the order of 200 years ). Once LED manufacturers are fairly confident of LEDs lasting in real world conditions for 200 years, you'll start to see 50 year warranties. There is already some precendent for such long warranties with things like windows. Driver electronics probably won't last that long, but you can locate them so they're easily replaceable in the field ( bases of streetlights would be a good spot ).


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## Curt R (Nov 8, 2011)

If there is a profit in it they will do it:

WASHINGTON (AP) — "Sprinkling" sounds like a fairly harmless practice, but in the hands of sophisticated counterfeiters it could deceive a major weapons manufacturer and possibly endanger the lives of U.S. troops.
It's a process of mixing authentic electronic parts with fake ones in hopes that the counterfeits will not be detected when companies test the components for multimillion-dollar missile systems, helicopters and aircraft. It was just one of the brazen steps described Tuesday at a Senate Armed Services Committee hearing examining the national security and economic implications of suspect counterfeit electronics — mostly from China — inundating the Pentagon's supply chain.
"The failure of a single electronic part can leave a soldier, sailor, airman or Marine vulnerable at the worst possible time," said Sen. Carl Levin, D-Mich., chairman of the committee. "A flood of counterfeit electronic parts has made it a lot harder to have confidence that won't happen."

I do not trust them with my lights. Check everything.

Curt


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## deadrx7conv (Nov 9, 2011)

Sprinkling? Toss some 'Airsofts' in with the Colts...

We have a 5mm fade testing thread. Its worth a read. 

I doubt that they'll ever catch up with Cree or other quality manufacturer. They could possibly flood the market with cheap to reduce NameBrand sales causing financial stress then buy NameBrand outright. And, obviously that is what OP is pushing. I think that the typical US consumer is now looking for a little bit of quality and not just 'cheap'. We've seen how well that has worked out in the pass decade with most other discount imported products. 

And, the XPG can be run at 4w-5w. The XML can be run at 8-10w. Lets see how well those import LEDs do when stress or pushed a little. Running them at 1/2w or 1w is nothing to brag about. 

If you're producing lights that use 100's of LEDs, then there are cost savings. What is your reputation worth? 
If you're looking to use dozens of these in a single light, you need to look at bigger LEDs from Bridgelux, Sharp, Citizen, Edison, LedEngin......

With the possibility of a dysfuntional Euro, and the typical tired of being laid off and stepped on US worker, I also wouldn't count out a trade war to prevent any country from dominating any one industry. Those rare-earth exports that are limited and controlled are teaching many countries and manufacturers a lesson. Nationalism might just rear its head and make a comeback. What happens if someone wakes up to the unfair trade practice, patent/trademark infringements, rampant industrial espionage..and finally tags their 'most favored' WTO/MFN trade status?


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## sandos (Nov 9, 2011)

I just bought 2 pcs of 10W leds from ebay, they are most likely "generic chinese" ones. They didn't cost 12$ a piece though, but 5$ so I couldn't resist. Had a very nice tint but doesn't seem terribly efficient. At this price they are still interesting, especially if they are more efficient at low drive currents. To me the price per square mm of led is interesting


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## degarb (Nov 9, 2011)

blasterman said:


> It's a bit of semantics when we refer to 'Chinese LED's' given it's near impossible to find a product not made in Asia. However, there is a distinction between LEDs designed and produced by Western Companies vs LEDs produced by Asian manufacturers who are simply flipping production lines at night or sharing semiconductor recipes in the black market.



The Chinese need to work at branding (building confidence), quality control (honesty), and not stealing technology. They are good at packaging and sprinkling in just enough good 'parts' to keep the consumer contented (usually 1 good part to 2 bad).

They probably don't brand very well because they stole the patentents to make the darn things.

It is possible to compete with someone who makes 10x less, with skill and technology breakthroughs. You simply cannot compete with someone who steals your ideas. Without patents, we would still live like people did in the 1700s.


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## Nil Einne (Nov 29, 2011)

blasterman said:


> Over in a salt water forum I submitted some 10watt Chinese LEDs so a member could test them with a spectrometer, and the results compared to base Cree's were pretty made for the Chinese tech. Compared to XT-Es the popular SEMI based Chinese LED that's rampant on Ebay is maybe half as efficient. If you'd like to challenge those conclusions be aware you are on the wrong side of the facts.
> 
> Given the fact that the market for cheap emitters is based on price and not performance there's no need for the Chinese to 'up' their technology. Cree, Bridgelux, Luxeon , etc., are in a race to build the most efficient emitters, or they lose business. The Chinese can sit on old tech and ride out Luxeon III based technology because they are selling at a cost per lumen perspective and they can post specs with fudged numbers few people can read. The mere fact I've pointed out so many times that a Bridgelux is not only cheaper but is actually brighter than the more expensive 10watt Ebay emitter proves this out.


 


blasterman said:


> As long as I'm having to explain half a dozen times a week in this forum and reefing forums to somebody that a $12 10-watt SEMI based Chinese LED with a rated range of 400-800 lumens bought on Ebay *is not* a better deal than a $8.50 800 lumen Bridgelux, then indeed the Asian
> semi-conductor industry is going to win. Mostly because American consumers are too retarded to make intelligent choices based on junior high school science. Game over - inability to penetrate skull.
> 
> This has nothing to do with bigotry or flag waving, but the basic ability for educated consumers to read simple specifications. If LED #1 is more efficient, brighter, costs less and is posting reliable specs from Western company than LED #2, LED # 2 is not a better deal because it's posted on Ebay.


 
I'm not saying the Chinese emitters are a good buy. But I think your point on 10W LEDs is flawed. Anyone buying a 10W Chinese LED on eBay for US$12 is indeed an idiot because it doesn't matter what the actual specs on the LED are. 10W LEDs sell for under US$5 in single quantity. 20W LEDs sell for under US$9 again in single quantity. (I'm including shipping in both prices.) Even if you don't trust the cheapest ones, it doesn't make any sense to spend US$12 on a 10W Chinese white LED. 

Also where is this US$8.50 Bridgelux come from? Something like Newark or something? If so, remember this is likely only really relevant for those in the US and a lot of people do live outside the US. The trouble with Bridgelux is they're difficult to reliably find on places like DealExtreme, eBay, Aliexpress which ship from HK/China. Finding them on these sites is important for some because if you're only buying one or two, shipping kills the deal outside the US (and possibly parts of Europe). It doesn't matter if the LED is US$8.50 if you pay double that when you take in to account shipping. (If you're buying other things from the same site and can combine shipping, great, but if you're just a hobbyist doing a one time thing you may not be.)

Also realisticly eBay and similar small level sales must be a tiny portion of the market for LED manufacturers even cheap Chinese ones. If they're hoping to make it big by relying on selling to small scale consumers, they've set themselves up for failure. But I'm pretty sure Chinese manufacturers are competing for the wider wholesale market such as those who use their LEDs in products, like the OP. Perhaps I overestimate that market, but I'm pretty sure when someone designs a product to be product in quantity, they don't just rely on lumen specs on eBay and particularly for cheap Chinese LEDs. They can probably get more reliable specs out of the manufacturer but I'm guessing most designers will evaluate products from manufacturers before deciding what to use. Yes the manufacturers can use a variety of methods outlined like sending good samples which the production quantities don't come close to matching to try and fool such testing. And later sprinkling good with bad to make it difficult to catch even in production. 

In other words, I find it difficult to believe the Chinese manufacturers aren't competing on a dollars per lumen basis. They must be, because the only way they can compete is on cost as is always the case with no name Chinese products, and cost is meaningless in the abstract (I think we can all agree a _single_ Nichia 5 mm LED isn't going to win for home lighting against a Cree XM-L even though the Nichia is obviously cheaper.) As people have said, no one is going to buy them for consistency, or reliability, longivity, or colour performance and tint, and definitely not efficiency. They buy them for cost. And even if some of those who source them are rely so dumb as to rely on the Chinese specs without testing and these specs are wildly inflated, ultimately in a competitive market place these manufacturers are going to die. Their products won't be able to compete because when they try to sell them to businesses, government or consumers in the developed world they can't e.g. advertise wildly inflated specs because their LED manufacturer lied to them on the output. And even in the developing world, people tend to know not to trust the specs and while things can be confusing, it doesn't mean the company which tells the biggest lies wins so having an okay product usually matters. So those using name brand LEDs will be able to sell a cheaper product or make more profit if their name brand LEDs were cheaper per lumen. (Remember they can potentially choose a cheaper lower power LED from the name brand, and also bullshit about the specs of their product with the name brand LED.) 

Of course one of the ways many of the Chinese manufacturers do this is by poor overall products i.e. as I've said means poor consistency etc clearly undesirable for any one using their products. Another way is by not caring if they violate patents while copying. Which is somewhat undesirable for a business. Although some the people in charge may not personally care about such practices, they have to consider the small risk to them for using products which violate patents. From an ordinary consumer POV, some would care, some don't. (I don't want to get in to the ethics, simply pointing out that not everyone cares.) 

This doesn't mean the Chinese LEDs on eBay are the most effective on a price/lumen for consumers. They may be, they may not be, but not by enough to be worth it. You can get Cree XM-L for under US$9 including shipping from HK/China which beat the 10W and must come close if not beating the 20W. (The 20Ws often seem to be advertised as 1000-1100 lumens and based on the assumption this is likely inflated by at least 20% I'm guessing it's about 900 lumens or less so likely loses to a XM-L.) All run at close to max power of course. And even if the 20W LEDs beats a XM-L, the lower efficiency and all the other issues makes it's a questionable proposition, particularly since you'll probably be spending something on the heatsinking and PSU+driver so it's only part of the equation. And theoretically you have to spend more on the heatsinking. (I say theoretically because of course people may overestimate the heatsinking meaning they end up spending the same. Or they may underestimate and end up killing their Chinese LED.) 

When it comes to coloured LEDs these are more tricky since name brand ones are harder to source from places like DX, eBay, AliExpress. Again if you live in the US and parts of Europe you may be able to source them from local manufacturers without being killed by shipping and possibly price for small quantities. Ditto if you're buying say 10-20 (depending on price range of LED) or a regular customer with some supplier. Although even then I don't know if it's always so clear. For example, you can get 20 red '3W' for about US$23-26 all up. The price for 11 (chosen because of price break) Red XP-E from Cutter is AU$29.59 (AU is close to par with US at the moment) without shipping (or taxes if you're Aussie). For me shipping adds another AU$9.00. I know the 3W Chinese red LEDs are unsurprisingly worse then Cree XP-E's https://picasaweb.google.com/100774...AnalysisOfLEDCombinations#5604432572847116770 at 700mA and surely they're worse at 350mA too (athough it wouldn't surprise me if not by so much) but are the Cree's really worth it? Obviously they still have an reliability and longevity advantage. But tint/colour is obviously less a concern. And efficiency and heatsinking requirements would be better for the Crees but may or may not be a big concern. In other words, I wouldn't necessarily everyone choosing the Chinese ones are making a mistake. 

P.S. I'm not saying there aren't a lot of dumb buyers on eBay etc. I'm the kind of person who sometimes bids on those auctions which Chinese/HK sellers run where the price can be a crapshot, and I see how common it is the winner pays significantly more then a buy it now auction for the same product from the same or different seller.


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## jashhash (Dec 7, 2011)

I have been running 4 sample LED's in an integrating sphere non stop for a month now. All four LED's have been over driven to 1.6 watts each and the solder point temperature has been kept at a consistent 85-87 Degrees Celsius (over heated). So far the Component shows a lumen loss of less than 0.5% from initial readings. Even though the components are driven hotter and harder than spec they are still projected to run 30,000 hrs before reaching 70% initial output. In the street lighting business failure is defined as reaching 70% initial output.


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## idleprocess (Dec 7, 2011)

jashhash said:


> Even though the components are driven hotter and harder than spec they are still projected to run 30,000 hrs before reaching 70% initial output. In the street lighting business failure is defined as reaching 70% initial output.



I have difficulty imagining 30,000 hours being an acceptable lifespan for what is typically a very expensive element in a luminaire and difficult to replace - that's less than 7 years at 12 hrs/day. But I also don't claim to know the market for streetlights.

What's the projected time to 70% based on this accelerated abuse testing if you don't mind saying?


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## jashhash (Dec 7, 2011)

30,000hrs is what's expected in the accelerated abuse test. Under normal operation the LED should last 50,000 hrs.


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## jashhash (Dec 8, 2011)

30,000hrs is what's expected in the accelerated abuse test. Under normal operation the LED should last 50,000 hrs.


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