how long do 5mm REALLY last?

voodoogreg

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I have gotten in the habit of hanging an ultra G from the ceiling to light the computer keyboard. I got into it when mom would be napping in the recliner, But now I enjoy the effect of the room still dark but the computer in the nice
glow of the G. And with the use of nimh's it run's pretty much 24/7 since i forget to turn it off 8 outta 10 times.

well I got to thinking about the estimated life of nichia LED's, and others (I think the CMG stuff was nichia) as to the fact that they don't live in the 50-100,000 Hr's like we had been told. So I took it down and i put two new L91 lith AA's
that metered exactly the same, and got my other ultra's that was pretty identical in beam, throw, brightness to this "G" and darkend the room and studied the beam's.

It was very apparent the G was now more then noticably dimmer. i wonder if anyone has noticed this? it's usable, but lets say i would not have picked it out of a batch of other ultra's. (i'm sure someone else also does this, If possible, open up a few and check which Is brighter, tint, etc)

I got 4 ultra's,, two G's, and two std CMG ultra's. They were my first "good" aluminium LED light's, so i know them pretty well as far as which was a little brighter, or big spill Vs hotspot etc, so I am sure of what I am seeing. (in fact my least bright ultra is now brighter then the "nite lite" G.

wadda ya think? does anyone know at rate this happens? I think i remember the ultra's are not puched real hard like say a ARC AAA. discuss.VDG
 

Stu

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That's an interesting observation, VDG. I haven't had LED's going that often, but I'm eager to hear what others say about their constant usage of similar lights. How long have you been doing this with the Ultras? More than a year?
 

voodoogreg

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Stu said:
That's an interesting observation, VDG. I haven't had LED's going that often, but I'm eager to hear what others say about their constant usage of similar lights. How long have you been doing this with the Ultras? More than a year?

I would say nearly a yr 10 mth's? and i should add i would consider it mild abuse in away. Also i am real stupid about electronic's for flashlight's, and maybe it could be the circuit losing some juice??
Yes i too want to know if other's have seen this, and theories for the reason it happen's. Not really bummed, just curious. Im was just lucky to be in this postion to know my light's
since i am picky about beam quality, and knew the differrence's of my ultra's. VDG
 

greenLED

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Since you don't really have a baseline observation telling you what the original brightness of the "G" was, any inferences you make right now will be inadequate. What you can do, is take note of the current brightness (use a light meter and setup conditions you will be able to repeat) and remeasure/compare in 3, 6, 12, months.
 

voodoogreg

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greenLED said:
Since you don't really have a baseline observation telling you what the original brightness of the "G" was, any inferences you make right now will be inadequate. What you can do, is take note of the current brightness (use a light meter and setup conditions you will be able to repeat) and remeasure/compare in 3, 6, 12, months.

I would tent to agree, with the idea of having had metered all four before and after. But I do feel my constant playing around and noting which were imo brighter/better is still pretty clear to me. I also noted each with a # I wrote inside the cap and on the inside tube of 1-4. "1" being my best, to "4" my the least bright. # 2 is the ceiling light, and now it's noticeably dimmer then #4.

Not scientificI know, but i was so anal about my little ultra's I am certain what the base line was both in memory and by # rating. By how much it is fallen off i don't know.VDG
 

SemiMan

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White -- 5-10K hours. The epoxy they are encapsulated yellows. That is one of the big differences with the high powered LEDS. You may be able to find some low power SMT parts that also have non-epoxy encapsulation. In addition 5mm has a poor thermal path making things worse.
 

voodoogreg

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SemiMan said:
White -- 5-10K hours. The epoxy they are encapsulated yellows. That is one of the big differences with the high powered LEDS. You may be able to find some low power SMT parts that also have non-epoxy encapsulation. In addition 5mm has a poor thermal path making things worse.

thanks semiman, that makes sense. I take it this does this by use not age? VDG
 

Brlux

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Hi I have had some experience with the cheepo white Chinees leds. I purchased several off ebay and used them to light up my room. I had 105 of them in the room runing of solar power and they were on nearly 24 houre a day for a little over a year. They were driven at only about ~25mA but after a year they were nearly useless. They had all dimed substantually and turned verry blue in tint. I realize that these were lower quality leds but after a year at close to their rated drive curent they were seriously degraded in under 9K hours.

Brlux
 

leukos

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voodoogreg,

are you sure there is no corrosion on the contacts? My CMG sonic requires cleaning rather frequently.
 

Kiessling

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jayflash said:
My arc AAA lost 50% of its metered brightness after about 10 cells changes in two years.

After all that isn't a surprise as the Arc puts about 50mA through the LED that is rated at 20-30mA IIRC. This is like putting 2000+mA through a LuxIII ... :eek:oo:
We never paid much attention to those little 5mm LEDs, but why shouldn't they be allowed to fail under severe overdrive?
That is why I avoid overdriven lights for quite some time now!

bernie
 

ledled

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I also wonder how Nichia & Lumileds accurately rate their LED lifespan. I don't believe they took thousands of sample in their lab & turn it on for 10 years continuously to test. I'm very conservative on overdriving Leds as I don't believe they last the advertised hour driven at spec or even 1/4 of that.
 

voodoogreg

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leukos said:
voodoogreg,

are you sure there is no corrosion on the contacts? My CMG sonic requires cleaning rather frequently.

absolutely. I have a pretty major cleaning regiment.(search for "lubing your light" type threads, i lay it out in detail, no use repeating here) so that is not it.

Kinda OT on my own thread but does anyone know what the little hole in the head is for? I used a plastic pick and it goes pretty deep, but i can't see into it. Didn't know if it was an adjustment port of some kind.

I also tried different batt's, alki, lithium, nimh still the same result's. VDG
 

Moat

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Hi, VDG - I believe the hole in the circuit board is where the un-cured potting compound/epoxy is injected, after the board is crimped into place.

FWIW, I have two 2001 vintage V2.5 Arc AAA's - one unused, and one that's been in my pocket since new - and used regularly. It's probably only seen 6-8 battery changes, but had no perceptible difference in brightness when compared to the unused one, after four years. That is... until I recenty installed a C0 bin CS Nichia!

Although, the V2.5's didn't drive things as hard as later versions, AFAIK.
 

voodoogreg

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Moat said:
Hi, VDG - I believe the hole in the circuit board is where the un-cured potting compound/epoxy is injected, after the board is crimped into place.

FWIW, I have two 2001 vintage V2.5 Arc AAA's - one unused, and one that's been in my pocket since new - and used regularly. It's probably only seen 6-8 battery changes, but had no perceptible difference in brightness when compared to the unused one, after four years. That is... until I recenty installed a C0 bin CS Nichia!

Although, the V2.5's didn't drive things as hard as later versions, AFAIK.

thanks Moat. I had that musicians mind set of being something I can trim and return brightness. (A lot of guitar effects have one or more trim pot's in them for fine tuning before you close the box up.)


Hmm, I think ARC and CMG both used nichia's, I wonder how much current is going to the LED in the ultra in comparison to the ARC. I had read here somewhere that the ultra is not OD'ed or only a little overdriven, making it such a good light for camper/outdoorsy types.

Could it be battery related? I use the ROV IC3 nimh's, and love em. Not had much problem with them. could it be? (calling silverfox!) VDG
 

Moat

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voodoogreg said:
I had that musicians mind set of being something I can trim and return brightness. (A lot of guitar effects have one or more trim pot's in them for fine tuning before you close the box up.) [ENDQUOTE]

Har! Like this fellow pedalgeek's latest aquisition - a Blackstone Appliance Mosfet Overdrive... bristling with trimpots and replaceable caps. Understood!!

I had measured an Ultra's drive current at one time, and from (foggy) memory, it drives the LED at around 65-70ma with a fresh alkie... and visually appears (to my eyes) harder driven than an Arc AA in side-by-side comparison (the Arc supposedly around 45-50ma, which seems about right). In any case, IMO the Ultras are significantly overdriven, but also appear less so when ran with NiMH (I use the ROV IC3's as well).

FWthat'sW.
 
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PhotonWrangler

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I built a little device that uses a 5mm white LED as it's power LED. I've had this device running 24/7 for about 2-1/2 years now. The LED isn't a Nichia. It appears subjectively to be a little bit dimmer than I remember it when I first powered it up, but it's still quite bright.
 

voodoogreg

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Moat said:
voodoogreg said:
I had that musicians mind set of being something I can trim and return brightness. (A lot of guitar effects have one or more trim pot's in them for fine tuning before you close the box up.) [ENDQUOTE]

Har! Like this fellow pedalgeek's latest aquisition - a Blackstone Appliance Mosfet Overdrive... bristling with trimpots and replaceable caps. Understood!!

I had measured an Ultra's drive current at one time, and from (foggy) memory, it drives the LED at around 65-70ma with a fresh alkie... and visually appears (to my eyes) harder driven than an Arc AA in side-by-side comparison (the Arc supposedly around 45-50ma, which seems about right). In any case, IMO the Ultras are significantly overdriven, but also appear less so when ran with NiMH (I use the ROV IC3's as well).

FWthat'sW.

Blackstone, WORD! killer pedal,keep playing with it till you get "your" tone. I mainly a tube OD guy and if needed use a boost into the amp for solos slide parts, But the BS is the only pedal along with a radial classic that sound like a real tube being clipped. I use both often in session's when an engineer is impatient :ohgeez: :whistle: good buy brother!

Well, well, since the ARC run's hotter, I gotta think this is just normal with my (ab)use. enjoy that pedal. if your into boost's you you may want to look at the one i make: www.lockhartfx.com lets talk gear sometime in the cafe sometime! peace bro. VDG
 
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Moat

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Wow - sweet pedal, with great reviews on HC! I've never used a boost, but there's always room on the pedalboard... if not, just build a bigger one... eh?! My amp search gene is currently highly active (Bad Cat CubII on order) - when I get THAT settled on (if ever...?!), I'll certainly give your boost a try, pronto. Congrats on that thing, man!!

Sorry for the OT, everybody...

I've found that a Nichia CS upgrade to an original (low output) Infinity is about 70% as bright as a stock Ultra - that might be a good long-term, lumen maintenance option for this kind of use, as I don't think the LED is overdriven at all in the original version.
 

offroadcmpr

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I wonder what manufactuers define as a total life. Slight dimming, half brightness, or until it not longer produces any light whatsoever. It is most likely the last one. Kinda like battery runtime plots. Sure it produces light for 80 hours, but it only produces useable light for 3 hours. After 80 hours you can not even read a book when the light is 6 inches away.
 
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