Match, thank you for your valuable information with these tests. I have had a 3-4 XML build swirling around in my head and this thread is rich on information. It also answered my curiosities on the SST50's. I know the thread is a bit dated now, but hey, I'm the "new guy". Im guessing that similar info is at cpf but it seems I can hardly stand looking over there for more than 5 minutes at a time.

Have you done a "pop" test for giggles on a XML?

Also something else I would like to see charted- temperature on a smaller given heatsink say after 5 minutes being ran at 2.4A and the same test at 3A.

When I say poof test I meant cranking it up (A) on the bench until critical failure.

Match, really thanks for all this effort to provide some good results with a scientific method.

But i am pretty sure that you have done a major mistake in your test methodology, the pcb. You are suffering from high thermal resistance,this pcb is a bottleneck to the great cooling you supply to make this test.

The pcb you selected to make the test is one of the worst i have tested. Even the round 16mm kd/dx base is performing a bit better(the 14mm cutter and dx/kd 14mm base are worser than both, they have a lot of thermal resistance). I don't have any scientific data like you, but after numerous tests, KD 20mm star or 22mm star from illumination supply are much better. Therefore, you can get better results.You would be amazed if you test a 30mm pcb from an olight M3X.

So,i am pretty sure it is possible to get higher performance and over 1000 lumen with a XM-L. With the excellent pcb olight provides, i am measuring almost 970 OTF with a 4.2amp driver. So, it should be over 1100 lumen on the led.

Next time you would like to repeat this test, take this factor into your account seriously. Again thanks for all this excellent test data and really happy to help you with any way(leds, pcbs etc)

Match,

I feel all LED companies should provide charts like yours. I also wish that there are more drivers available...

Thanks for the graphs, this is the first time I have seen them. This is going to make my flashlight selection a lot easier in the future 

Awesome work Match! it's just GREAT!!

Many Thanks for sharing

Awesome job Match thanks

maybe slightly off topic and out of date but is there any test like this with XR-E Q5 emitters as i see alot being driven past 1 amp and all the data sheet,s i see are one amp max i would like to see flux and maybe heat ratings from a Q5 when you push them hard can any one point me in the right dirrection ?

benckie wrote:

Awesome job Match thanks

maybe slightly off topic and out of date but is there any test like this with XR-E Q5 emitters as i see alot being driven past 1 amp and all the data sheet,s i see are one amp max i would like to see flux and maybe heat ratings from a Q5 when you push them hard can any one point me in the right dirrection ?

Joining this poorly disguised plea for Match to include the XR-E in this eminent research.

I have a couple of the latter overdriven from stock as well.

just found this page courtesy of a member of my forum linking it.

well done! The data with the XM-L matches my own testing

I can see why I dislike the SST50's performance so much, too

C

Match you are awesome!

I just read the whole darn thread and I´m just still baffled by your dedication to "knowing" and your easy way of passing the info on down the tube. 

Aplaudable indeed 

Thanks Match. I always wondered if an sst50 could be driven to approach the surface brightness of an XRE. This might do well for a thrower, but then you are well into the power requirements for a descent HID.

Outstanding job Match, I learned a lot after your post. Thanks

Match,

While taking a second look at your test results, Ive decided to scrap the ideas of building a mega high output SST-50 thrower. When examining efficiencies while driven at high current levels, the SST-50 simply isn't a logical choice when compared to the SST-90 or an HID.

I assume that you used the XM-L U2 1C during your tests? Since most people will probably mod using a driver with 8 x 7135's, its very interesting to compare your measured lumen outputs at 2.8A.

Emitter       Lumens

XM-L          852

MC-E          693

SST-50       708

A few interesting realizations (for me):

* To achieve the same luminosity of the XM-L @2.8A, the SST-50 needs approximate 3.6A, while the MC-E requires 4.4A.

* The XM-L gains only 29 lumens when going from 2.8A to 3.0A.

Typical flashlights lumens will suffer far greater losses as heat rises. More often, high junction temperatures are reached fairly quickly. Considering the XM-L, it really does make sense to run at lower amps, especially for applications that run continuously for long periods of times (searchlight, bike lights, etc.) This gives me some great ideas for my next 3 x XM-L bike light. Thanks for all your hard work.

Very informative thread. Thank you very much!

Do you plan on adding more LED types to the tests? XR-E R2 (WG) perhaps, and SST-90?

thanks very much for running these tests.  This is incredibly useful for making informed decisions.

I have a question though, that I don't 'think' has come up here - if the emitter(s) were actively, and well cooled, would we see a higher peak output?  Ok, it would seem obvious it would increase at least some, but I wonder how much.

Really though, what would be useful, is if it extended the nonlinear relationship of input/output.  Instead of plateauing around 2.4-2.8...to say 3.5

Thanks very much for the response.  I've had an internal debate for weeks on buying copper PCB xmls (instead of aluminum) for a project.  I think it will be worth the extra money to buy copper.

I think you're right about the impracticality of a peltier.  But let's hope for some new advancements in battery technology to change that

Even if they do, it will probably be up to us to build such things - at least on MY budget...

This post has really become my reference post when deciding about current levels.

Thanks a lot M8

That's crazy I have been pushing XPGs to 2.2 amps (8 chip Nanjg driver with 2 removed) because that's were they looked the brightest by eye and it was right on the money.

Many thanks for this addition, Match!

(Standing by for the XR-E ...  )

I would really love to se an XP-E or XR-E q5 led in the mix. I still like them.

-Garry

2.2A  xpg is exactly what the N-light B2s stainless steel lights are running on the 14500 ..

           always got a ..."WOW that's bright".... from the crowd ...

                    ooooohh....aaaahh.

And what would be a similarily "bold" current for an XR-E?

oldbobk,
        So are you saying the affect on runtime is negligible between running 1.4A vs. running 2.1A?  That doesn't make any sense to me. 

        I also don't know if I'm up to the challenge of removing two of those chips!  I'd probably look into the newer KD driver (and deal with a lousy low, or go 2 mode).

-Garry

garrybunk wrote:

oldbobk,
        So are you saying the affect on runtime is negligible between running 1.4A vs. running 2.1A?  That doesn't make any sense to me. 

        I also don't know if I'm up to the challenge of removing two of those chips!  I'd probably look into the newer KD driver (and deal with a lousy low, or go 2 mode).

-Garry

The difference in run time with a 2400mah battery would be about 100 minutes for the 1.4 and 70 minutes for the 2.1 amp high, but I never use high when I am concerned about runtime.

Send me a PM when you are ready to remove the chips I can walk you through it or I can send you one premade if you want.