Well I ordered a Z1 to host my precious new emitter in received from Led4power today, Really nicely packed an sealed and the reflow looks expertly done!! , I also ordered the Convoy L6 , what can i say… I have a problem and banggood baited me with their 30% off promotion…
Anyway I’ve now read this thread start to finish 3-4 times excellent posts from many of you one thing i would really like to know or see is some kind of chart that references emitter lifespan with amps, I note some of you want reliability and some of you want the fastest standing quarter. it would be nice to have even just some estimates of emitter life vs current
For example (Assuming well mounted in a good thermal host)
at stock 3 amps 10,000 hours
at 4 amps
at 5 amps
at 6 amps
at 7 amps (A few seconds)
Unless i’ve missed it that doesnt seem to be covered on here
You wont find that anywhere. How is anybody supposed to get that data? We are driving these LEDs outside the official specs. Realistically you will never have problems if you don't go right to the edge. The internal temperature of the LED is the important thing here.
I do led testing but not that type and you will never get that data I can tell you. Led failure is a chance proces so the set-up is at least 10 leds per current, so 40 leds for 4 currents, 40 independent current controlled power supply outlets totalling at 800W, continuously burdening my electricity bill for say half a year. And at that is a lifetime measurement on just 1 singel led.
Not asking for exact data , an experience based opinion would be fine, if i run a white flat at say 4.5amps is it going to last hours , days , weeks , months , years ? typical based on experience how long does one usually last or is it totally random?
LEDs are very interesting in the power cycle department. Traditionally, incandescents are affected strongly by power cycling and the related thermal expansion/contraction stressing the filament. Flourescents (and compact flourescents) have always fared even worse with power cycling - the 10,000 hour CFL bulbs we all got sold 15 years ago were great for fixtures that were on constantly or at least for long periods at a time and rarely cycled. LEDs themselves don’t care a whole lot about power cycling, especially within rated specs. That’s why LEDs have been used for anything that blinks for as long as it has been practical. In the case of residential LED bulbs, it’s almost always the driving circuit that fails.
But I could see LED power cycling being an issue eventually, especially in above-spec applications and especially with things like bond wires. But the thing the manufacturers seem to care the most about is operating temperature in general, rather than temperature cycling. Might be worth a look into research papers on the subject.
As long as you’re keeping the LED cool enough, I’d expect it to last a while. Many months if not years of continuous use. I’m sure we won’t see the rated 50k or 100k or whatever it is hours, but I’d be surprised if we hit the output degradation threshold sooner than 10k hours. Which reminds me, the way LEDs are typically rated for lifetime isn’t a failure point, but rather a lumen decay issue. When I worked on the retail side of things, the primary bulbs we sold were rated for 80% output after 25,000 hours for “22 years expected life”. I know the % varies depending on who is rating what, but it’s probably usually 75-80%.
If your re-flow or cooling is inadequate it could be hours. Most of the LEDs that die around here die in hours or after the first few turbo uses.
If it survives that and you have good firm contact with heat sink and appropriate cooling it will probably last a lifetime of normal use. You may see some total brightness decrease over time but this is like single digit percent drop over years. Lets just say your switch will probably fail before your LED.
Ok so basically then if you want absolute concrete reliability and total confidence in your build stick with 3amps , if you want to push the envelope and everything goes well it could last quite a while (months to years) , if you made a mistake on the build you’ll know pretty quickly (within hours) but provided the sink pad is properly mounted to the host with good thermal transmission and you have a reasonable quality driver for the most part they will take the extra amps fairly reliably and have a pretty good service life?
Guys , I’ve finally got the L2 host and dropped in CULNM1.TG with a P4000 buck driver, While it is quite impressive it is nothing like the Aspheric
Im not sure if my focus is correct, ive used the supplied White Square hole spacer that comes with the L2 host , and also tried without it fitted. Without it i get a tighter hot spot but beam artifacts (yuck) , with it i get a very slightly wider hot spot and zero artifacts do you mod the spacer at all?
Yes, modding the spacer is key to get a laserpointer beam.
Simon sells the 3030 gaskets, which helps getting centering right. Focusing is another thing though.
I have sanded down several gaskets until i got focusing almost perfect and reached a tolerable beam.
Exactly, but lower is not always better, try to find the ‘sweet spot’
On the other hand, artifacts are the effect of bad centering.
Probably you have an xml and xpl sized gasket. Not the 3030 gasket which is required for the Osram.
Well It looks like i’ve just figured out how much is to much… i do have a spare at least don’t suppose you have a link to the 3030?
Edit: #Attempt2#
Hey thats pretty dam good now, makes my eyes hurt when i look at the spot on the wall and there are no artifacts THANKYOU!! :sunglasses:
Does anyone have any figures for KCD using an L2 host and a somewhat over driven White flat?
pic!
If you’re anywhere near Devon i have a Z1 with a white flat you can try.
