Anyone use up the lifetime of their LEDs?

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HBomb
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Anyone use up the lifetime of their LEDs?

Just out of curiosity, I see all these 100,000 or 80,000 or 50,000 hour lifetimes for LEDs. Has anyone actually used a light up to that point? I doubt anyone has, but I can never be sure so I thought I'd ask. What is supposed to happen when an LED reaches the end of lifetime? Does it just dim or burn out or what? I have been in the habit of tailstanding some lights as makeshift night lights and wonder if that would be wasting the LED's life. 50,000 hours is around 5.7 years on so I should be fine anyway. Especially as I buy more lights Silly I am wondering if they just put a number out there for the sake of the shock factor.

how2
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This is under optimal conditions. The led is probably driven at 350mA.

You will never get this. My Ultrafire MCU C7 Led only lasted 2 years. Look here.

M3TAL_L0RD
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LEDs just usually get dimmer. And LED lifetime is usually "measured" to 70% of lumen remaining.

HBomb
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Thanks how2, very interesting. I am usually on low for the night light use so heat won't be as big a problem hopefully. Did it die slowly or instantly?

 

Edit: I assume slowly then. Thanks for the input ML

CheapThrills
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I have a multi-5mm-LED night light, 230V and E14 socket.

It used to give some light. Now I just recently compared it to a flashlight. It is brighter than my iTP A1 on LOW but noticeably dimmer than iTP on MED.

I quess it would be near 5-20 lumens. Yes, on a 230V E14 25LED light.

 

It used to be as bright, that it had to be dimmed like with a pice of paper, not anymore...

kragmutt
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What are some estimates of the life of an XML driven at 2.8A then? Seems like most of us are doing that, although probably not for extended periods of time.

Boaz
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Solder another 3$ q-5 in it and go another 5 years

       καὶ τὸ φῶς ἐν τῇ σκοτίᾳ φαίνει καὶ ἡ σκοτία αὐτὸ οὐ κατέλαβεν

                                  https://www.gty.org/

 

    Still selling diffuser film  >…  http://budgetlightforum.com/node/42208

Oxy Moron
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In industrial and military applications, LEDs do have a projected EOL (which is part of the procurement spec) and are to be replaced before that date, if the application is critical. Think of it as LEDs having a "best before" date. Well, that's how it's supposed to work in theory. In the real world, it's just not a concern (translation: nobody, except us freaks cares, because as far as the rest of the world is concerned, if you flip a switch and there's light, it's all good :D)).

For the most part, adoption is so slow that mission critical systems are still using decade old technology (and for a very good reason: it's been thoroughly tested, we know it works and, more importantly, we what to do when Murphy's Law strikes) and where LEDs have been widely deployed, people will usually only notice when multiple LEDs fail or start to flicker at the same time.

Don
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The original quad-die LED the Luxeon V was notorious for losing a lot of lumens rather quickly - like about 500 hours to 50% and a rapid decline thereafter - an LED with a unit cost at one point of around $50.

http://www.dansdata.com/da5w.htm

 

I've used up all the life of a bunch of 5mm LEDs in about ten seconds - I should have paid rather more attention to the voltage I was feeding them from a 60A capable supply.

Burnt optical epoxy smells utterly vile.

 

The numbers from my light tests are always to be found here.

https://spreadsheets.google.com/ccc?key=0ApkFM37n_QnRdDU5MDNzOURjYllmZHI...

HKJ
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Lifetime of leds is depend on temperature, i.e. a led that runs hot will have considerable shorter lifetime.

For 5 mm leds this is often a problem, they cannot get rid of the heat from inside the plastic body, i.e. running them at a over current (as most flashlight does), will burn them out and this might happen within a few 100 hours.

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/