5-Watt "Terra Destroyer"

[Kenshiro]

Craig,

Thanks for the pics.
It really cleared up a lot. I've taken a lot of photos of lights myself, and they always seem to be different from what my eyes see. I guess that's what happened here, too.

It's all relative, I guess. The lights I mean.
Seeing the 5W next to the Hydra or Electroblaster, you can really see the difference. But the lights next to the Illuminator, well..... I guess they're both so much brighter that the camera simply shows them as being "much brighter". If you know what I mean.

Sorry for the 3 messages. Something went wrong with the server and I kept getting error messages, so I did it three times.

Thanks again.

 

[Gransee]

The housing temp sounds familiar...

These lights are going to be quite warm to the touch. The LS2/LS3 will have caution labels on the bezel and a thermal shutdown onboard to protect the circuit. If you let go of the light, walk off, come back 10 minutes later and reach for the light, it is going to sting a little.

I've been startled by the LS3's temp more than once. Usally, the light gets dropped and then you shut it off by wedging it between your shoes.

Of course, we have taken steps so that the LED is not being destroyed. That is the whole point of a derated design. The max die temp is 135C. with a case temp of 65C (150F), we measured a die temp of 85C, well within limits.

Still, they get quite hot from the perspective of the human hand. It is either that, or make it dimmer/larger. Since most of the time these lights are used for less than 5 minutes, it won't usually be a problem.

Here's a twister, are these 5w emitter flashlights more efficient than the "cooler" running incandescents they replace?

Peter Gransee

 

[Lux Luthor]

OK, the light gets hot. We've all known for a long time that this would happen. BUT, let me pose a very sincere question to everyone:

Is there any reason why you would want to run such a light for 30 min. continuously? If so, please post, because I honestly don't know why.

That is, unless you use the one flashlight system.

 

[hotfoot]

Shouldn't lights that get as hot as these have some sort of heat-insulative ribbing (made of rubber or composites) around the head or something? That should take maybe 50% outta the ouch factor without affecting metal-to-air heat dissipation too badly. It could be a bolt-on/slip-on accessory so that the all-metal-flashlight purists out there won't get upset, but those who'd rather not have BBQed hands will have a solution for long-duration usage.

With this next generation of LEDS lights, you'll know for *SURE* if you've left them on in your pocket! Ooo... the underpants meltdown effect...

 

[Gransee]

The 95/5 rule applies well to the EDC class. This means that 95% of the use is less than 5 minutes in duration. But all it takes it one 20 minute use to change your opinion on the light either for good or bad.

I have handed prototypes to people without saying anything and let them play with it. They usally say something like, "huh, its getting kinda warm" and then continue whatever they where doing. No complaints yet. I have never handed it to anyone hot. That would just be mean.

Btw, to answer your question more specifically, here's some +5min uses:

- Changing a flat tire/roadside engine repairs
- Putting up a tent
- Looking for firewood
- reading a book (not recommended with these lights!)
- looking for something in the attic/tool shed, etc
- Night fishing
- Walking the dog

etc..

Peter

 

[Gransee]

Originally posted by hotfoot:
Shouldn't lights that get as hot as these have some sort of heat-insulative ribbing (made of rubber or composites) around the head or something? That should take maybe 50% outta the ouch factor without affecting metal-to-air heat dissipation too badly. It could be a bolt-on/slip-on accessory so that the all-metal-flashlight purists out there won't get upset, but those who'd rather not have BBQed hands will have a solution for long-duration usage.

With this next generation of LEDS lights, you'll know for *SURE* if you've left them on in your pocket! Ooo... the underpants meltdown effect...

<font size="2" face="Verdana, Arial">A light with a good heat sink will be the same temperature from head to tail. Adding raised, insulated grips will help in comfortably grabbing the light but will also reduce the surface area for radiating the heat. This will raise the temp even higher.

Adding a small muffin fan would do loads for this design but it would make it more difficult to waterproof. We have already discussed this before..

Btw, Kudos to Wayne and Don on their excellent mod! They are two very sharp people who have been involved in the LS2/LS3 design so this is familiar territory for them. Jollyroger also had some influence on this design.

And my compliments to Craig on another excellent and exciting review.

Yes, the cyan is brighter than the white. The E2's beam is still more concentrated than the white 5W w/the NX05 optic (stock). The 5W produces more lumens, but the beam is quite wide so it seems dimmer in side by side comparisons.

Peter Gransee

 

[Lux Luthor]

Originally posted by hotfoot:
Shouldn't lights that get as hot as these have some sort of heat-insulative ribbing (made of rubber or composites) around the head or something? That should take maybe 50% outta the ouch factor without affecting metal-to-air heat dissipation too badly. It could be a bolt-on/slip-on accessory so that the all-metal-flashlight purists out there won't get upset, but those who'd rather not have BBQed hands will have a solution for long-duration usage.

With this next generation of LEDS lights, you'll know for *SURE* if you've left them on in your pocket! Ooo... the underpants meltdown effect...

<font size="2" face="Verdana, Arial">I think this kind of setup relies heavily on heat dissipation at the outside surface of the light - both by radiational and convectional cooling. I think if you wrapped it in insulation, you would stifle these effects quite a bit. Just MHO.

 

[hotfoot]

Originally posted by Lux Luthor:
</font><blockquote><font size="1" face="Verdana, Arial">quote:</font><hr /><font size="2" face="Verdana, Arial">Originally posted by hotfoot:
Shouldn't lights that get as hot as these have some sort of heat-insulative ribbing (made of rubber or composites) around the head or something? That should take maybe 50% outta the ouch factor without affecting metal-to-air heat dissipation too badly. It could be a bolt-on/slip-on accessory so that the all-metal-flashlight purists out there won't get upset, but those who'd rather not have BBQed hands will have a solution for long-duration usage.

With this next generation of LEDS lights, you'll know for *SURE* if you've left them on in your pocket! Ooo... the underpants meltdown effect...

<font size="2" face="Verdana, Arial">I think this kind of setup relies heavily on heat dissipation at the outside surface of the light - both by radiational and convectional cooling. I think if you wrapped it in insulation, you would stifle these effects quite a bit. Just MHO.</font><hr /></blockquote><font size="2" face="Verdana, Arial">Agreed, Lux. That's why I suggested ribbing. This would leave wide gaps in between the ribs, exposing the metal beneath. The ribbing I'm thinking of should perhaps cover a maximum of 30-40% of just the head area (the bit most likely to get hottest) and leave the rest of the light unadorned. Heat will still be able to dissipate thru the rest of the flashlight and not concentrate in one spot. I know of some performance car tweaks that insulates the exhaust headers so that it doesn't radiate back into the engine bay, but further down the exhaust line. This improves enginer performance. In a flashlight, it'll keep you from getting scorched. And as suggested, it could be an add-on, so that in situations demanding max dissipation, the accessory needn't be used. Fully optional

 

[Lux Luthor]

hotfoot,

Sorry, I didn't read carefully enough that your idea was to elevate your hands from the light, while still retaining most of the surface area of the metal to be free to cool to the outside atmosphere. I think that's an excellent idea!

 

[hotfoot]

No worries, Lux!

I've been working with Luxeon clusters in small packages quite a bit these last few months and you're absolutely right about the heat that needs to be dissipated - every single square inch exposed really counts!

cheers...

 

[Doug Meister]

Yikes, as someone said: that is Frighteningly bright. I want a white one. I wonder if it will require a cryo-cooler.
--Ðøug

 

[The_LED_Museum]

Just got Wayne Yamaguci's (sp?) new 5-watt green LS conversion from Don McLeish (who built the thing into a Surefire Centurion body), and boy, what an eye terrorizer!!

Pictures?
Sure... why not...
Camera and lights are 3' away from wall, camera settings not changed from light to light.

See that pitiful, faint bluish tinge on the left? That's coming from the 19 screaming white LEDs in a Tektite Expedition 1900 Limited Edition.

Next is the CMG Reactor, using lithium batteries.

This is the Arc-LS, using the 2x AA pack.

Finally, this is a Lambda Illuminator. It's the only one that even tried to put up a fight.

I shined the thing at my poor, deliberately tortured Euro-Pro Bagless Stick Shark vaccum, and I think it melted a hole in the tank. Next, it boiled all the water out of my toilet, and set my bedroom curtains on fire. Good thing the fire dept. was here today testing the building's fire alarm. :9

I can honestly say, "This is THE BRIGHTEST LED I've ever seen."

 

[**DONOTDELETE**]

I don't care if I need to have EDC oven mitts!! I want one!!

 

[Daniel Ramsey]

And to think I have paid for 20 of these.....

 

[caver]

Another 5+ minute use: caving. A headlamp could be on for 24 hours or more.

One of the reasons some cavers still use carbide lamps is they can be used as heat source. Sounds like cozying up to a 5w will be nice... and smell better too

 

[d'mo]

So much for the "opposition" to the proposed 1 hour run time of the Arc-LS3. Looks like everyone likes a bright one.

Originally posted by Gransee:
here's some +5min uses:
- reading a book (not recommended with these lights!)

<font size="2" face="Verdana, Arial">I would think the book would burst into flame

 

[Doug S]

Peter, something doesn't compute.

Originally posted by Gransee:
I've been startled by the LS3's temp more than once. Usally, the light gets dropped and then you shut it off by wedging it between your shoes.

Of course, we have taken steps so that the LED is not being destroyed. That is the whole point of a derated design. The max die temp is 135C. with a case temp of 65C (150F), we measured a die temp of 85C, well within limits.
Peter Gransee

<font size="2" face="Verdana, Arial">Elsewhere in the ARC forum you have told us that the LS3 runs at 2W. I am assuming here that you mean 2W delivered to the LED. Per the 5W Luxeon datasheet, using their mounting methods they achieve a thermal resistance of 11C/W from the die to the surface its mounted on. At 2W, thats 22C. Now from there, the heat has to travel to the case of the light. Heat to flow, requires a thermal gradient so there must be even more than 22C from the case to the die.

 

[yclo]

Hmm...

 

[geepondy]

Originally posted by Gransee:
The housing temp sounds familiar...

These lights are going to be quite warm to the touch. The LS2/LS3 will have caution labels on the bezel and a thermal shutdown onboard to protect the circuit. If you let go of the light, walk off, come back 10 minutes later and reach for the light, it is going to sting a little.

I've been startled by the LS3's temp more than once. Usally, the light gets dropped and then you shut it off by wedging it between your shoes.

Of course, we have taken steps so that the LED is not being destroyed. That is the whole point of a derated design. The max die temp is 135C. with a case temp of 65C (150F), we measured a die temp of 85C, well within limits.

Still, they get quite hot from the perspective of the human hand. It is either that, or make it dimmer/larger. Since most of the time these lights are used for less than 5 minutes, it won't usually be a problem.

Here's a twister, are these 5w emitter flashlights more efficient than the "cooler" running incandescents they replace?

Peter Gransee

<font size="2" face="Verdana, Arial">Do you anticipate the LS2 getting warm enough to induce thermal shutdown? With the LS3, it sounds like you're moving away from the Arc philosophy of a "light you can depend your life on" to lights of a more tactical nature. If I'm lost in the woods, stranded, etc., I don't want a light that's going to get very warm and thermally shut off after a few minutes. If the LS2 doesn't exhibit these thermal problems then again, I'll state it here as many of us have previously said so, we hope that the LS2 will be a widely available item.

 

[The_LED_Museum]

Tried a little experiment this morning. Around 3am, I took the light and a pair of binoculars to the bedroom window, butted the end of the light to one of the eyepieces on the binoculars, and turned it on. It was enough to faintly illuminate the top of a building nearly a mile away! WITH A SINGLE LED!!!

After illuminating the building, I saw two windows on upper floors light up one after another - presumably people (still awake) who flicked on their bedside lamps after seeing this eerie green light in their rooms and thought there was a flying saucer outside.

There's a lot of light pollution in this area, so I might have done even better if I had somewhere truly dark to test in.

Also, if you wake up in the middle of the night and need to "go", *DO NOT* under any circumstances reach for a light like this to light your way to the can. You might as well flick on the bedroom light - the effect on your eyes is the same: pain and temporary blindness. Even shining it at the ceiling will illuminate the whole room brightly enough to cause momentary discomfort and blindness afterward.