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An Irreverent Look at the LED Industry

Posted March 07, 2017 12:00 AM by Engineering360 eNewsletter

Here's an in-depth look at the past, present, and future of the LED industry. This interview with Ed Rodriguez debunks myths, discusses industry trends, and recent events. He'll also tell you what he thinks many people get wrong about the LED industry.


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Re: An Irreverent Look at the LED Industry

03/08/2017 12:25 AM

A very interesting, but mostly negative, article.

I've thought about that 50,000 hour lifetime many times. 50,000 hours≈2083 days, ≈5.7 years of continuous use. I have a red LED-display clock that ran continuously for over 20 years. None of its LEDs ever failed. Every one of the 208 red LEDs in the display of my 1978 TI calculator still works (as does the calculator), and as far as I can tell, they are just as bright as they were almost 40 years ago. Obviously, it has not been turned on continuously, but the reliability has been perfect.

Now clearly the above LED examples were not driven at high current, so it is not a true comparison to LEDs intended for lighting, but they do show that, under the right conditions, LEDs can indeed last a lot more than 50,000 hours.

It's been well over 10 years since I first checked out a couple of defective red LED street stoplights. The defects were all bad solder joints; The LEDs were all good.

I've been switching over to LEDs for nearly all of my home lighting, for 6 or 8 years. There are still a few incandescents, and a few CFLs left, but you have to search to find them. I definitely prefer the color of the (mostly cool white) LEDs over incandescents; and the energy saved is considerable. I really appreciate not having to be careful to avoid burning myself on the high intensity desk/work lamps. I'm especially happy with the (just under) 4 foot work Lamps (from Costco) I've installed in my Shop area.

Early on, I did have a few partial and complete failures of LED lamps, but again, it was the solder joints or the power supplies that failed, not the LEDs, and none of those I've purchased in the last couple of years has failed.

I'm DEFINITELY pro-LED!

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Re: An Irreverent Look at the LED Industry

03/08/2017 3:19 PM

You are comparing apples to oranges. The LED's in a display are so low on power, you can't tell if they are on by touching them. I can warm my hands during a winter bike ride with my "950 lumen" bike light, and that is by touching the aluminum case, which is an obvious serious heat sink. The LED "60 watt" equivalent bulb in my local reading light by my chair gets warm enough that I really don't want to touch it. The bulb may be cool, but the heat sinks are cooking along pretty well on these miracle lights. Not as much wattage lost to heat as incandescent, but the very localized heat extraction points get quite warm. That has to cause a deterioration over time much greater than your old display LED's.

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Re: An Irreverent Look at the LED Industry

03/08/2017 3:36 PM

"You are comparing apples to oranges."

I indicated that in my second paragraph.

It is quite clear that heat sinking is a major part of designing successful LED illumination devices.

Still, I've never seen any LED lamp that would burn you instantly, like my halogen desk/work light that just burned out, used to. It clearly will not be replaced with another halogen lamp.

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Re: An Irreverent Look at the LED Industry

03/08/2017 6:36 PM

I've never heard of an LED fixture starting a fire, could you provide some examples? LED's are more efficient than incandescent or fluorescent types so they produce less heat...is this not true?

https://www.lightrabbit.co.uk/are-led-light-bulbs-a-fire-risk

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Re: An Irreverent Look at the LED Industry

03/08/2017 9:56 PM

Neither have I. Where did you see a reference to an LED fixture starting a fire? From whom are you requesting examples? (I presume the OP).

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Re: An Irreverent Look at the LED Industry

03/09/2017 7:06 PM

In the interview he calls them fire hazards....You need to click on the interview...

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Re: An Irreverent Look at the LED Industry

03/09/2017 9:22 PM

I did read the interview, and now re-read parts of it. One company had to recall some LED lamps due to overheating/smoking. Clearly there was a design flaw in the power supply/controller of that particular model(s). I consider such occurrences as a normal part of the development process. Presumably that company changed or discarded that design, or went out of business.

That certainly does not warrant a generalization that LED lamps are fire hazards!

...and now I saw your post at the bottom of the interview, and know that you were referring to the author or the interviewee of that article, when asking for examples.

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Re: An Irreverent Look at the LED Industry

03/08/2017 9:47 PM

As a matter of interest I made a box project that's just now over two years old.

It has a couple of D cells and a double throw switch. I decided that one of the LED's was so efficient that I would skip any possible 'off' position. It's either on or on. It's over two years later and yes, it's still on.

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