LEDs on Ebay; Lies, truths and false promises

LEDs on Ebay; Lies, truths and false promises (updated 2014)

To finish with the analysis of the lighting LED today, I am going to discuss my experiences with tests LED lamps to replace the dichroic (typical 50W halogen).
Update: I was surprised Ikea with their 600 E27 LED bulb lumens for €7, totally recommended. Also have 430 lumens for €5! They seem to be quality, SMD technology. Someone who has tried them can tell us?
Lately the LED are taking off, even if they are expensive, they represent a good investment in the long run.
However there are many stores that have them and their demand is low; they are evolving so quickly that you risk to have your expensive obsolete product and without selling at the store. In this case online stores like Ebay is an option.

Long eye: If as a consumer don't you want to carry a disappointment by buying on Ebay, you must be very careful; most try to present his product as the best true or misleading advertising by half; they tend to be Chinese lamps and the owner promises certain lumens and duration of the LED and the majority of the cases is not true.
If buy it bulbs, who gives you security that you can claim them if they give you problems within a year or two? Nobody gives you security that you respond, that they remain in the same place and even less to continue selling on Ebay. They may disappear once because they have "lined"...

Today, cheap LED lights fail to give the same light than a traditional light bulb, to obtain the same intensity, you have to pay the price; between 15 and 30 euros.
You do not take you data on prices and powers at foot juntillas because it becomes obsolete quickly; changes in the LED technology are still vertiginous, and I can not be updating every month yields and prices.
They can still replace certain points of light when a 50W halogen bulb is excessive.
When buying on Ebay, contradictions and falsehoods (proven) more common that I find the following:

  • They indicate you have more lumens of the real ones. Current consumption LED technology gives about 80/100 lumens per watt consumed, not you fiĆ©is ad that tells you to "consumption 4, 5W with 513 real lumens". That are 114 lumens per watt! A record of efficiency, right? And at a price of €9 per unit... too good to be true. The current record is in 150 lm/W, and not manufactured lamps still with that kind of materials; It would be too expensive. There are 120 lumens per watt, but they are also expensive. It is normal with this consumption have some 270 lumens, not much more.
  • They indicate that they have eg. 360 lumens and are "perfect to replace a dicroic 50W", when in reality 2 lamps would be necessary in order to give the same light; a 50W halogen gives about 18 lm/W; about 900 lumens. The announcement must indicate "Could replace a halogen of 50W", but that is never "perfect" or "ideal".
  • They promise more longevity , which are very likely to have. For example indicate 50,000 hours, when it is likely that not reach 20,000. Power LEDs are expensive, because they have greater amount of active material (which converts electricity into photons), and to reduce costs, what they do is apply more intensity and better; refrigerate Thus you get more of a same LED light but shortening his life to half or less. If you are going to a store and you look at the Philips, manufacturer of prestige, in its maximum LED lamps promise 25,000 hours; they are similar to the Chinese, with similar or better quality LEDS and with better quality covers in general.
  • The most common "deception" is to indicate e.g.. the lamp has 3 leds of 3W (3x3W) and actually consumes just 5W. Something does not block, and is possible to have 3 leds of 1W.
Do not be fooled... the most reliable way of knowing the approximate real lumens (depends on the quality of the led) is by multiplying the Watts spends 90, and if you want to replace one 50W Halogen Recessed, keep in mind that almost any dichroic LED lamp gives 900 lumens needed, at the moment you have to make you with 600 lumens that give better them (although there are, but they are more expensive).
Also you must be of the opening angle (the amplitude the focus reaches to illuminate). It is not the same 60 ° to 120 ° opening; If you want to illuminate all alike and not only a point concrete, much more generous, better. This is achieved regular plastic (polycarbonate) lenses placed on the top of the led.

To buy on Ebay with warranty it is best to check the positive feedback; If people are happy with the results, they tend to be unreliable.

What LED lamp choose? Evolution of LED technology
When choosing the type of lamp, we have to go to the most recent, and ensure higher quality, duration and light per watt. LED lighting technology has evolved as well:

(Above) The DIP LEDS are those that more problems are by design and cooling; dan among 60/70 lm/W; are the first generation of LEDs; are they still used for electronic indicators

(Above) Technology SMD (Surface Mount Device), more recent and efficient; between 70/90 lm/W but with only 50% efficiency by eliminating heat. There are many types, its main advantage is the flexibility of mounting. They are usually manufactured from 0, 1W up to 1W of power

(Above) COB (Chip On Board) technology: Linking directly to the aluminum base semiconductor allows you to effectively remove heat from the union, managing to extend its life and reducing costs. Its effectiveness is between 90 and 110 lm/W

MCOB technology (Multi Chip on board) is the latest generation of LEDs, widely used in the lighting of street lamps and tunnels today, this technology is most effective (between 100 and 140 lm/W) and cheaper to assemble than multiple small chips lamps. The most known companies are working on this technology, such as Bridgelux (USA) or Edison and Epistar (Taiwan).
There are companies as it believes that manufactured fully integrated power LEDs (from very small size), ideal for high power lamps, but their price skyrockets.

As always with LED technology, the key to its duration and power is the chip performance and the quality of the driver, but that means nothing if you do not have adequate cooling. There are some lamps, especially the first, which is manufactured using existing, crammed into glass casings, such as halogens:

I wonder it occurred what brilliant engineer make such barbarity, total absence of cooling
Fail immediately due to its total lack of refrigeration, are the first that were manufactured for consumption, and warm that they are scary, passing the 100 ° c, I do not think that they last or a year, then begin to overheat and fail, shutting down groups of LEDS until there is none, or losing all its intensity.
LA CLAVE: refrigeration and the quality of the diode. A good lamp led stays below 60 ° C operation (as discussed in the previous post), with a good design of the heatsink, and their diodes are manufactured with enough semiconductor material and quality (to better quality of led, less generated heat and longer duration). How to know which one to choose? Those who have the latest LED technology and greater surface area contact with the air.
Changing halogen bulbs to LED
Careful with the dichroic 12 volt led; usually the transformers for recessed lights give one slightly higher voltage, which negatively affects the duration of LEDS 12 volt; make sure before you buy that they are prepared to endure 14 volts, or lament it in less than a year. You will see as the leds go dark, losing brightness, to burn with the use. The ideal here is add a small transformer that secure 12V or change the type of bulb to GU10 which goes directly to 230V, and also save the consumer having the transformer.
Council: Where your recessed halogen bulbs go to 12V ( MR16 or GU5.3plug), it is better to change the system to GU10 changing just the socket (plug) and elminando transformer, for 12V transformer 50W-ready and because of itself has an even greater than the LED lamp (12W in many cases while the led can walk between 6 and 9W). In addition the potential problems are reduced operation (flashes, partial lighting of lamps, etc), and removes the buzzing transformer 50W. On this page you have further information to change them.
Any reliable shop?
I am not going to recommend any shop; I don't want to influence in a free market. Only comment that they are increasingly available in more stores, and that there are companies like Arkoslight assembled and built their own lamps in Spain, although most of the items are of foreign manufacture, I guess, but it's something to contribute to national progress.
Seek, compare following the signs for lighting, refrigeration and price, as well as the guarantee of duration, and you will be on the right track.

You buy the brand you buy, I recommend testing one hour a lamp before; If you can not touch it (rises 80 ° c), return, it won't last long. Even think you put them in small and completely watertight; sites they overheat and your life will be shortened much.

What lamp is the most appropriate?
Everything depends on the power. If we replace a halogen 50W, we will have to go to one of 8W 9W LED, that between 700 and 900 lumens, quite close to the light emitting halogen bulb of 50W, about 1000 lumens. Above all it must be refrigerated (having space to "breathe"), to greater power, greater sink and more efficient (there are more efficient than other designs), but in general the best is to take that look like these:

Image: Bazarled

Of actual 9W replaces one 50W halogen quite well, and the 3W are valid to illuminate pictures, like a 15W halogen and 6W is like a halogen 25W, but consuming only 6W. (These are values for lamps that give 100 lumens per watt, but increasingly are more efficient, so that in coming years they still illuminate more consuming less )).

Update: This is an example of good product GU10, with front opening so that air can circulate freely, and 5730 chips quality from the very best and most durable in Chinese product with 600 lumens for just € 4, I've seen it in DX.com, but safe which is also the same price in Spanish pages (DX is nothing more than one more a reseller):

GU10 lamp 500 lumens with good ventilation
And here's an example of good lamps for few euros in MR16 (GU5.3).

As I've said before, is the more recent technology used, longer and brighter will have.