MC-E maximum drive current.

[qwertyydude]

Does anyone know what the max drive current for the MC-E is? Not what is stated on the datasheet, 700 ma per die. But if you can drive an xr-e at 1.5 amps reliably would it be possible to do the same with the MC-E and have a 6 amp light possibly producing 1000+ lumens? I know at peak I've seen as high as 4 amps with a fresh 18650 unprotected cell, protected cells only can manage 3.3 amps and some trip their protection circuits too.

 

[AaronM]

It really depends on how you mount it.
If you use a normal star or epoxy the emitter directly to a hunk of metal, that tiny non-metallic layer is nowhere near as thermally conductive as the metal parts, so the performance may suffer.

If you solder just the thermal pad of the emitter to a hunk-o-metal, the sky is the limit.

This L2 head is wired 2s2p and can handle 3.5 amps for about 90 seconds.
With more than 25W going through such a small head it gets hot fast!

 

[deadrx7conv]

17w limit????

http://www.candlepowerforums.com/vb/showpost.php?p=3098815&postcount=336

Probably get a little more light with the M and N bins.

 

[bigchelis]

This one is driven at 4A with no tint shift. Power source is 3 niMH Tenergy subC cells via DD. With bigger cells at 1.43V each it goes to 4.5A, but still white tint too. I dont know which bin it is?:confused:


2lbs of copper for a 2D Blaster is overkill???? No way Jose!!

 

[AaronM]

17w limit????

http://www.candlepowerforums.com/vb/...&postcount=336

Probably get a little more light with the M and N bins.

It says the SST-90 in the test is mounted to a copper slug, but no mention of the thermal arrangement for the MC-E.

Also, in my defense: I merely answered with the facts I have discovered on my own. It WILL take a ton of power with out blue shifting if mounted correctly.

Will it be any brighter @ 1.8A per die than 1.2A per die? I have no idea, but the evidence you provided doesn't leave me feeling very hopeful. =o[

Speaking of witch: Hey BigC, ready to do some more measurements?

 

[qwertyydude]

I ran mine at 4 amps but I think ultimately it's the heat dissipation that got to it. After running it through a couple hours of testing I noticed the phosphor traces near the bond wires starting to turn ever so slightly brown. It's not ruined in the least but efficiency has dropped about 15-20% according to my camera from a ceiling bounce. It's now only slightly brighter than my XP-G whereas before it was noticeably brighter.

The thermal conductivity even on a star at 4 amps is enough to prevent any tint shift but continuous running will build up a lot of heat in any flashlight, it got warm fast so I know good heat conduction but it eventually got too hot on continuous running.

I guess I'm going to stick with the recommended 2.8 amps on the next rebuild of my MC-E wow light. Got the parts on order. Too bad though because at 4 amps it is truly impressive but I want actual usability not a hot potato after just a few minutes of use.

 

[Walterk]

Lovely pieces there Aaron and Bigchelis!

 

[PCC]

Lovely piece there Bigchelis!

That thing looks like crap. I mean, c'mon, who made that thing anyway? A monkey? Hehe, that was not my proudest work. BTW, that thing only weighs about 0.75 lb due to the length and the holes that I bored into it for the switch and stuff.

 

[Justin Case]

This one is driven at 4A with no tint shift. Power source is 3 niMH Tenergy subC cells via DD. With bigger cells at 1.43V each it goes to 4.5A, but still white tint too. I dont know which bin it is?:confused:


2lbs of copper for a 2D Blaster is overkill???? No way Jose!!

Photo looks like a 4P MC-E, which would mean 1A per core at 4A DD. AaronM's 2S2P setup delivered 1.75A per core.

That big copper sink is great. Ideally, to take full advantage of it, soldering the MC-E directly to the sink would have been the way to go, instead of mounting a star using what looks like some thermal adhesive. However, it looks as if directly mounting the MC-E sans star is not necessary in practice since you have been able to run the LED up to 4.5A (about 1.1A per core) with no issues. The mod'ing creativity shown by CPFers is boundless.

 

[arrrx]

Does anyone know what the max drive current for the MC-E is? Not what is stated on the datasheet, 700 ma per die. But if you can drive an xr-e at 1.5 amps reliably would it be possible to do the same with the MC-E and have a 6 amp light possibly producing 1000+ lumens? I know at peak I've seen as high as 4 amps with a fresh 18650 unprotected cell, protected cells only can manage 3.3 amps and some trip their protection circuits too.

6A for 1000+lm？maybe SST will be better.and the high current,the low efficiency.it's a problem to solve the hot sink.

 

[qwertyydude]

That's OTF lumens. assuming the mc-e is like the q5 led, extrapolating at 1.5 amps from the performance chart, you're looking at about 300 lumens/die. So this is close to 1200 emitter lumens and that's not taking into account the better optical efficiency of the mc-e package what without the metal ring. It's comparable to the sst-50 in terms of efficiency while being a whole lot cheaper.