Fenix L2D on turbo mode for prolong periods?

I finally took the plunge and got a Fenix L2D Q5. Its a nice light, good beam, feels well made. Its not a bright as what I imagined it to be, but on turbo mode its not too bad.

However I noticed that it recommends you do not have the light on turbo mode for more than 10mins. I find that on high its not really that bright. Is the 10mins on turbo an over precaution... will it actually be ok the use turbo mode for longer periods of time?

The idea of the 10 minute max is to stop it overheating. On high mode, you can run it until the batteries run down and it'll never get more than "warm". On turbo, it can overheat. However, being outside with moving air from walking/wind, holding it in your hand, mountainbiking, etc, all remove the heat far better than standing in still air, so you'll be fine unless it's tailstanding indoors somewhere.

I've got two of the P2D Cree's that recomend the same 10 min max. Both my wife and I have by accident, clicked on the light that was in turbo mode until the battery died. Neither time were they fresh batteries, but I'm quessing it ran for a good half hour each time and had no ill effect to the light's performace when we replaced the battery. Can't tell you how hot it got, we figured it out after the batteries were long dead.

I've also ran my PD30 on turbo till the batteries died with no issues,the light was hot but nowhere near my L4.

I used my P2D and my brothers on Turbo to run battery tests on Streamlight, and Ultralast Cr123 batteries. I ran them on turbo until the batteries were dead. I did place a small fan on low on the lights since they were not being held in the hand to move heat away from the light. Niether light ever suffered a problem.

I am quite surprised you don't think the L2D is bright, especially for its size. I now own the updated version of the P2D the PD20 and it will always be one of my favorite lights. I also own the 2 aa battery tube which basically makes it a L2D.

Bill

Hitthespot said:

I am quite surprised you don't think the P2D isn't bright, especially for its size. I now own the updated version the PD20 and it will always be one of my favorite lights.

Bill

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Same here,i've got the PD20 too and this light can hold it's own with my E2DL.

I run an LD2 Q5 on 'Turbo' for at least 20 minutes non-stop almost every day, and have done so for several years. It's just fine.

I have used it constantly while caving on turbo with no problems, but the caves are 55'F and that probably helps cool the flashlight.

One more vote: I also have run a P3D-CE, a P3D rb100, and a P2D rb100 on turbo for extended periods. No ill effects.

I have accidently left mine on in a well insulated coat pocket on turbo. It was too hot to touch (seriously) but survived fine and was still just as bright as the other one after its ordeal. I would never recommend that it gets too warm to touch.

I used mine regulary when cycling on turbo mode and its a great bikelight.

I guess one of the things that should be said is that under normal circumstances LED's gradually lose their brightness and color. It's not like your going to leave it on for 20 minutes and have it go dead. I'm sure Fenix would never drive the led that hard even on Turbo. Today's LED's are usually listed somewhere between 30,000 to 100,000 hours. By continuously or occasionally over heating the LED we cannot be sure how it will affect its performance in the long run. The manufacturers warning is there for a reaon. Of course the next question is, does it matter? If I get 25,000 hours out of a light instead of 75,000 hours, do I really care? Heck by the time I dropped my Incand lights I usually got less than 2 hours out of the bulb!

Bill

Hitthespot said:

I am quite surprised you don't think the L2D isn't bright, especially for its size. I now own the updated version of the P2D the PD20 and it will always be one of my favorite lights. I also own the 2 aa battery tube which basically makes is a L2D.
Bill

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I just think in my mind i had unreasonable expectations that it would be brighter, it seems comparable to a ultrafire C3 that I used to have (until it broke), its does not seem that much brighter than DX's 'peoples cree' torch. I find on turbo mode the L2d is pretty bright, but on high it's pretty unimpressive.

Better is not always brighter. I am sure you will come to appreciate it more the longer you own it.

carrot said:

Better is not always brighter. I am sure you will come to appreciate it more the longer you own it.

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Words of wisdom as always.

It's not hard to make a light that is bright, just as it's not hard to make a car that goes fast in a straight line. The real challenge is making it reliable, with a good UI, efficient, etc.

As everyone has said, running it on turbo for more then 10 shouldn't be a problem unless you leave it running in a hot environment like in the middle of the desert on a sunny day or in a thermally isolated area like a coat pocket.

If you have it in your hand, a glass of water, on a bike, or anywhere where there is decent thermal transfer it should be fine.

As carrot said, better might not be brighter. Cheap lights can be brighter then good lights, but in the long run, quality, durability, support, and R&D wins.

My L2Ds are my blackout lights. I've used my L2D tailstanding in turbo on freshly charged 2650mah batteries until dead on several occasions, sometimes with a second battery change during an extended blackout. It got warm, but not so much I couldn't pick it up, so I would say <50C. I haven't noticed any ill effects. I would say you have nothing to fear if you are handholding the light. And like Hitthespot said, I don't care if I have degraded the 30000hrs lifetime to just a measly 10000hrs. Like others, I am surprised you are not satisfied with the performance especially considering this is a 2xAA light.

I'm just being picky

I does feel well built and well made. Might get the l1d body for future when I want something smaller. I have a fenix LOD Q4 though, which is my favourite light.

I thought the 10 minute on turbo warning was only for the Rebel versions. Cree l.e.d.s can handle more current and heat. I wouldn't worry about it unless you leave it tailstanding. If you're holding it, the heat will transfer to your hand and spread out to your body. I don't think this is that big of a problem anyway since it's the middle of winter.

brucec said:

I am surprised you are not satisfied with the performance especially considering this is a 2xAA light.

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I think that's what some people forget.

Hooked on Fenix said:

I thought the 10 minute on turbo warning was only for the Rebel versions. Cree l.e.d.s can handle more current and heat.

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Completely not true. If anything, rebels can take more current because there are no bond wires.