Which Emitters Have You Burned Up From Overuse?

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Rusty Joe
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Which Emitters Have You Burned Up From Overuse?

Have you killed (unintentionally) an LED from too frequent use? How long are your LEDs lasting? Are they living up to the “five years constant on” lifespans? I’d say, yes, but it’s ben known for quite some time that household bulb LEDs tend not to be as reliable as once thought (I myself have had a few fail).

I burned up an XPG2 in a 501B drop-in maybe six years ago. Made it to 10 minutes of runtime and then dead.

Any “browning” LEDs at present?

Correllux
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Flashlight emitters, just a couple of the Nichia 276 UV 365 that I was overdriving a bit more than Simon does in his stock S2+ light. Killed an XPL years ago but that was my fault either with too much heat/time on the reflow or perhaps a bad reflow…second trip at 3A it dimmed and died.

Household bulbs…don’t use them a ton at home but at the office where they have 10+ hours a day in various fixtures and temps, we go through quite a few. We have some large globe pendants running A21 bulbs base up, totally enclosed, around 2000 lumens (I think 18W or a bit more, can’t recall now)…those stay around 125°F which is a bit over their max spec even though they are rated for enclosed fixtures. It’s varied by brand but at best those tend to last about two years (although just had one last 2 years 4 months) and generally they crap out at 16 months give or take. This has been true whether parts of their housings have been plastic or zinc, simple mcpcbs or nicer thicker ones, potted board or not. I drilled 3/4” vent holes in the stainless top covers for those fixtures hoping to vent some heat and it doesn’t seem to have helped much at all. We have some bigger brighter corn cob bulbs in similar fixtures that, while running hotter and about the same hours per day, have lasted almost four years now (I think those are 26W). Open air bulbs seem to mostly do fine but we’ve had a number of the small decorative and fridge-sized bulbs die early deaths. Even the comparatively nice and well made Cree-branded A19 bulbs that were about $10 each didn’t last more than two years but those had very frequent power cycles.

In our flashlights, we almost always surpass specs and our heat management is far below the spec sheet optimums, so that mythical 50,000 hours claim doesn’t apply. Where the datasheets and whitepapers show lumen maintenance derating and such, it’s clear that by driving most emitters the way we do (even removing enthusiast turbo currents from consideration) we’re taking a huge chunk out of their possible lifespans. Ballparking it with something awhile back, around 22,000 to 25,000 hours seems more realistic for a robust high power white (forgive me, can’t remember which one I was musing over). That’s a lot of hours, though…pretty sure none of my lights have ever seen anywhere near that time.

Add improper reflow procedures and/or multiple reflows (most are only rated for 2 or 3 mountings) and it cuts down further. Most of the colored and UV emitters are much shorter lived even under the best operating conditions. I’d have to go look stuff up again but recently I was reading about various royal blue options and one was rated for about 10,000 hours lifespan at the pretty low datasheet spec current…in an aliexpress listing for a light using those the seller pasted the typical 50,000 hour claim…d’oh. I’ve seen UV lights advertised with 50,000 as well.

Keeping an eye on the two SFT40s I flowed…..

nicodimus22
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I still haven’t seen an LED fail, whether in a flashlight or in a light socket.

BlueSwordM
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None.

Even the light bulbs that have died on me still have perfect working emitters.

At this point, just actual driver heatsinking or derating components should be a requirement for light bulbs IMO.

My very own high current Beryllium Copper springs Gen 3:
http://budgetlightforum.com/node/67401
Liitokala Aliexpress Stores Battery Fraud: http://budgetlightforum.com/node/60547

Correllux
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I should clarify my longwinded comment above. In the household lights and such, I have seen several emitters burn (they all have been cheap plastic smd packages) and some did quit without showing any spotting or brownout. No idea how many we’ve been through…hundreds. I disassemble an awful lot of them just for a peek. Far and away it’s something on the driver that fails, rather than the emitters (most often seems to be the transformers in the lights that have them, but diodes as well…caps always seem fine). Most of those are not overdriven at all but the circuits supplying their power still seem to fall short of solid engineering. Topology and quality is all over the board and price/brand is not a guarantee.

Boaz
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none ...nada 

                 υμεις εστε το φως του κοσμου ου δυναται πολις κρυβηναι επανω ορους κειμενη

                            Dc-fix diffuser film  >…  http://budgetlightforum.com/node/42208

JenkinsMatti
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None.

Rusty Joe
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Now I want to test the limits of ALL flashlights I own with back-to-back battery change-outs when running on turbo perpetually!

Boaz
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For me turbo is a meaningless brightness level .

A  crazy high number that then drops like a stone within less then 15 seconds isn't one worth even measuring . 

 Back in the day the standard of almost all lights was one hour on high .

Maybe they were cheating back then too but not to this degree .

                 υμεις εστε το φως του κοσμου ου δυναται πολις κρυβηναι επανω ορους κειμενη

                            Dc-fix diffuser film  >…  http://budgetlightforum.com/node/42208

Rusty Joe
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Boaz wrote:

For me turbo is a meaningless brightness level .

A  crazy high number that then drops like a stone within less then 15 seconds isn’t one worth even measuring . 

 Back in the day the standard of almost all lights was one hour on high .

Maybe they were cheating back then too but not to this degree .

Those were the good days. And made complete sense.

zelee
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mine was cree xre, i’ve been using it for more than 10 years

Bob_McBob
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A bunch of my Hyperikon bulbs have failed, particularly the filament style. No surprise the company went bankrupt. I’ve never burned up an LED in a light but I sometimes do destructive testing with my bench PSU.

TIFisher
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No total burnouts, but the boost HX in my Astrolux EA02 has a fried segment from running a 21700 50E on its maiden voyage. I’m guessing the cell was crushing the tailspring, creating a sort of bypass, and the short bit of FET turbo swallowed all the juice from that fresh 4.2V. It’s pretty evident when shining on a close up surface, but it still throws the farthest of all my distance runners. I run an Sanyo 18650 GA in it now.

Lightbringer
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Not ever, at least not that I can recall.

All my daily-drivers, I don’t push too hard or use for extended periods. I also get to enjoy electricity and indoor plumbing.

Plus, for around the house, I typically “rotate” based on what I want ‘em for. Concealable “pocket-rocket”? GTmicro on momentary mode. Noises outside? SF47 or IF22A on turbo. Floody indoors light? SC31T. Kitchen-light for grubbling through cabinets? Tacklife w/ diffusion film. Etc.

Ie, not enough mileage on ‘em to matter, as it might be 30sec/wk? Well, except the SC31T, as I use that quite often for seeing what the little devils are doing in the house, looking for skeeters if I’m unexplainedly itchy, etc.

09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0

bobvoeh
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I’ve burned out some 5mm led’s when I first started modding flashlights 15 years or so ago, but nothing SMD yet. They were probably overdriven since they were just cheapo direct drive 3xAAA lights.

Henk4U2
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A few emitters did not make it, back in the good old XM-L2 days. Most of them in a led-swapping frenzy. Which tought me to pay more attention to tolerances. A few emitters were sheared off from the ledboard because of a tight fit of the centering ring in the reflector.

You are a flashaholic if you are forced to come out of the closet, to make room for more flashlights.

Unheard
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Dead LEDs in one small 12V bulb, several garden lights with PV charging.

Fixed the garden lights with resistors and the bulb with some of rngwns LEDs.

My 230V bulbs tend to die because of the driver, especially IKEA ones.

Smile, you cannot kill them all.

zoulas
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I thought LEDs don’t burn out they just get dimmer.

Unheard
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At least mine looked burned.

Smile, you cannot kill them all.

Bort
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No flashlight failures but LED lightbulbs i’ve gone through a few.
I suspect its the drivers dying and not the LED chips as all the chips stop working at the same time.

I take that back, one Convoy S2 failed but not sure why, and i can’t seem to find it and may have tossed it with e-waste without thinking a few years back.

The Journal of Alternative Facts

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acobp
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I had burned SST 40 in convoy S2+.
I open it and see that one of wires in diode has a break and I try to dedome diode and solder wire.
It works but only for 10 minutes and died again completelly.
I buy new diode at Simon store and it eorks now without problems.

kennybobby
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no failed FL emitters, but dozens of failures in the 120vac LED bulbs.

On disassembly i found tiny black dots on failed emitters. So called longer life bulbs, but most failed in the first year, maybe 1 or 2 made it 2 years. Several had just one emitter in the series string let go, but some took out the entire string.

Older versions had transformers and circuitry, now there is just a diode bridge rectifier, a capacitor, 3 resistor pads but only 2 populated, and a Joulwatt JW1981 LED driver chip.

JW1981 datasheet

Now i used to think that i was cool,
drivin' around on fossil fuel,
until i saw what i was doin',
was drivin' down the road to ruin. --JT

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Last winter I cooked an XHP-70 in my 2 cell hunting light. It was really cold out and my daughter and I were cleaning a deer and it was our only light. I think it condensed going from the house out to the field and about 20 minutes in it just got dimmer and dimmer. The dome turned black and I shut it off because the output was so low.

EDC rotation:
KR4, SST-20 FA3 4000k (favorite!)
FW3A, Nichia 4000k sw40 r9080 (second favorite)
FW1A, LH351D 3500k (third favorite)
FW1A, XP-L Hi 3A
FW3A, LH351D 3500k
FW3A, SST20 FD2 4000k
FW3A, Cree XP-L Hi 5A3
Emisar D4V2, SST20 4000k
Emisar D4V2, brass E21A 3500k (night light of choice)