L2D CE heat problem???

The Fenix L2D CE heats up quicky. It is normal for a cree led to have that much of heat?!?! Will it shorten the life on the LED because of the heat? It is a problem?

Just Curious, does the heat experienced at the head part only or it travels along the barrel as well?

What kind of cells are you using?

Mine does get a little warm around the head when on Turbo mode. Not only does
the Led get warm, the driver circuit also emits heat

My L2D CE runs perfectly cool in low and medium, warm in high, and quite warm (maybe 45oC) in turbo. I'm pretty sure this is normal, and provided that you are holding the torch or have it exposed to good cooling airflow it should not overheat.

Using 2650 mAH NiMh Duracells in constant use (Turbo mode) for 2+ hours, mine has never gotten more than slightly warm to the touch. However, with 2100 mAH cells, the case gets a little bit warmer towards the end of the battery discharge curve - perhaps a 25 degree F. temperature rise (?).

Had a similar occurance here.. I was using mine periodically last night and I guess I forgot to turn it off before I slipped it into my pocket so before i knew it, something was just about burning my leg so i pulled it out and it was almost too hot to handle. I was alittle worried i may have fried it but it's been working just fine since. Btw, I was running Maxwell alkalines.

redranger97 said:

Had a similar occurance here.. I was using mine periodically last night and I guess I forgot to turn it off before I slipped it into my pocket so before i knew it, something was just about burning my leg so i pulled it out and it was almost too hot to handle. I was alittle worried i may have fried it but it's been working just fine since. Btw, I was running Maxwell alkalines.

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yeaaaaah... is THAT normal?????

"yeaaaaah... is THAT normal?????"

I remember when I had my L1P and a similar thing happened.
Was out and noticed my leg was very warm. Pulled out an illuminatedly toasty little flashlight
Don't know how long it was on for, still had some juice left. Got fairly hot though!

Same thing happened with my LR12 when it was alive. I must have not unscrewed the tail far back enough and movement in my pocket caused it to turn on.
It was using a primary lithium cell and the little blighter didn't have much juice left at all - as it was in a cargo pocket I didn't notice the heat till i sat down! By then it was pretty pooped.

It can be a good idea to keep ones tailcap nicely lubed and use the LOTC functionality. Just aslong as you remember, and don't go stressing that the batteries are dead!

sorry but.. what's LOTC?

magnum70383 said:

sorry but.. what's LOTC?

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Lock-Out-Tailcap. It's not Fenix a feature (you can emulate it though) . LOTC is a SureFire patented invention.

magnum70383 said:

sorry but.. what's LOTC?

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As Outdoors Fanatic said, LOTC is originally a Surefire feature. It's a little more sophiscated for Surefires, but for the Fenix, all you need to do is unscrew the tail-cap a quarter turn, and you won't be able to turn on the light. This is to prevent accidental activation in a bag, pocket, etc. It's due to the presence of anodizing on the screw threads, which prevents contact unless fully screwed on.

I wish it was common on more lights, but you typically only see it on Fenix/Huntlight/Liteflux/Lumapower-grade of chinese lights. Hit or miss on streamlights, ultrafires, etc., and very rare on the cheaper knock-offs out there.

Oh, and the heat is normal. The heatsinking of aluminum lights is designed to transfer heat away from the LED and to the body of the light, getting quite hot without a proper cooling system. Cooling is normally provided by your own circulatory system as you hold the light in your hand (it will never get as hot if you are holding it the whole time). Left unattended, the light will get quite hot to the touch fairly quickly. The light should be alright, as long as you don't make a habit of it of leaving it on that way.

selfbuilt said:

As Outdoors Fanatic said, LOTC is originally a Surefire feature. It's a little more sophiscated for Surefires, but for the Fenix, all you need to do is unscrew the tail-cap a quarter turn, and you won't be able to turn on the light. This is to prevent accidental activation in a bag, pocket, etc. It's due to the presence of anodizing on the screw threads, which prevents contact unless fully screwed on.

I wish it was common on more lights, but you typically only see it on Fenix/Huntlight/Liteflux/Lumapower-grade of chinese lights. Hit or miss on streamlights, ultrafires, etc., and very rare on the cheaper knock-offs out there.

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Is that a patented feature?
I have done it for ages on all my lights, even the cheapest of the cheapest. Just unscrew until you dont have a connection anymore. Can't see how there can be a patent on that, would be like having a patent on the wheel.

Had the same question and emailed Fenix. This is what they say:

Hi Danny,

It is normal for it to get that hot on that drive level. Generally this does not
damage the light, however, if it becomes to hot to hold in your hand it would
be a good idea to turn the light off.

Regards,
Gary

Hello.
coppertrail asked "What kind of cells are you using?"
And so am i, the two of you who give the information have different answers, redranger97 used alkalines and the light got very hot, Skibanes light isn't so hot with Nimh, do you see a connection?

Since we know that alkalines don't have the power to make this light so glaring light, could it be so that alkalines get more warm than Nimh cells because they are more stressed?

Anders

and don't go stressing that the batteries are dead!

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now that i'm carrying a light that uses AA's, who cares if the batteries die (ahh.. so nice to be able to say that)! If that happened when i was carrying my Nuwai which uses 123A's I might have been alittle angry.

Since we know that alkalines don't have the power to make this light so glaring light, could it be so that alkalines get more warm then Nimh cells because they are more stressed?

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I don't know how/why it might be this way but intuitively, from looking at numerous run time charts and comparing the performance of alkalines vs. NiMH, that would be my conclusion as well.. which is why i have some NiMH rechargeables waiting for the alkalines that were provided with the light, to die.

Lobo said:

Is that a patented feature?
I have done it for ages on all my lights, even the cheapest of the cheapest. Just unscrew until you dont have a connection anymore. Can't see how there can be a patent on that, would be like having a patent on the wheel.

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On aluminum lights with no anodizing, the point where the contact is completely lost is usually the point where the cap actually falls off. I have many cheap lights like this (including SL, minimags, ultrafires, EJY, MTE, MDXL, etc.). There are tips and tricks you can do to help block current flow through threads, but I've never really found anything that works well (except anodizing, of course).

As for Surefires, their LOTC is a bit more complicated: for ex., on my L2 cap, up to a certain point the light won't come on at all (i.e. locked out), a little further and it will allow low mode in tactical manner (i.e. push on), a little further it will come on constant low, a little further for tactical high mode, and finally all the way for tactical on.

interesting... learned something new again... LOTC.

I've used my L2D CE for awhile and it's the coolest running of any of my lights on Turbo. Now my P1D CE at same brightness, that's a different story altogether. That puppy does get toasty (it could double as a hand warmer in the winter).