How do I explain that powerful flashlight gets hot easily at highest level is normal?

How hot is hot? Some Acebeam and Armytek lights get over 60°C, which is nuts to me.

That’s just it:

Hot to the point of burning skin is not normal.

Warm to the touch is normal.

If it gets hot QUICKLY, that’s actually better. It means the thermal path is good and it’s pulling heat away from the LED.

If they don’t understand it the first time you explain it, tell them to turn on a (incandescent) 100 watt light bulb, and then lick it after a few minutes.

At the very least, they won’t be able to verbally complain to you anymore.

…about sums it up.

Along the same lines, people want the hottest new light but they’re surprised when it turns out to be literal.

Yeh. They want controlled fusion in a lipstick-sized tube, then return it because “it gets too hot”.

FW3A step 4 draws 561 mA and generates 177 lm pluss heat. Turbo draws 12A. If the Leds were as effective as in step 4 the flashlight would generate 3800 lm, pluss propositional amount of heat as in step 4. For turbo you can then add 1000 lm extra light energy lost as heat energy.

How about:

“This flashlight has the same power as a household lightbulb. Please remember that it will get very hot at high power, just like the lightbulb. For your safety, we have designed this flashlight to reduce power after 3 minutes at high power.”

(You can write “on turbo” instead of “at high power” if you prefer.)

Don’t ask me how to make people actually read the warning, though :slight_smile:

No offense, but I don’t like the idea of giving Sofirn suggestions about more flashlights with timed stepdowns. A timed stepdown is the worst solution both for muggles and enthusiasts. Repetitive activation of turbo will still heat up the flashlight beyond its designated threshold unless a thermal controller is in place, too. But once you have a thermal controller (like „ATR“ called by Sofirn) in place you don’t need to have both timed and thermal stepdowns. That’s why I suggested to Barry to implement 3-4 user-selectable thermal thresholds for stepdown. Sofirn could sell their lights with a factory default of 45-50°C and put a big warning sign as well as some instructions into their manuals how to raise the threshold by hidden settings in the UI.

Say: “Powerful flashlights get hot easily at the highest level. This is normal.”

“LEDs don’t get hot.” is fake news :wink:

I really like what Phlogiston wrote.

Anyway, here is what I wrote a friend on the same issue:

Turbo is per definition only for a short time useable.
Turbo means you can’t sustain this level of output forever.

Like a 50m sprint on full pace or nitroglycerin injection in a motor. If kept for longer you overheat or the motor dies.

In todays flashlight it is normally one level below high where you can use it constantly. With a normal 18650 light that is 500 to 1000 lumen, depending how it is built.

LEDs produce heat as a incandescent light bulb, but only on a lower rate, but they do.

How hot the light gets depends on the output (the brightness setting) and how good cooling is (mostly the surface area of the lamp)

I know lamps with 5 seconds turbo time and some with 15 minutes.
3 minutes are quite long to light something up.
If you want a high output for long time you must buy big lights, e.g. the size of an old D-cell MagLigte

Fair dues :slight_smile:

I would prefer a light with ATR-style thermal regulation too, as long as I can choose the temperature, change back to a timed stepdown, or even turn ATR and stepdowns off altogether. There are people who actually like an abrupt stepdown as a useful reminder to think about what their light is doing.

My favourite lights have no stepdown or ATR whatsoever, because I know how to use them safely.

My text was just an example. Sofirn can certainly change that last sentence to something like:

“For your safety, we have designed this flashlight with Automatic Thermal Regulation (ATR). This will reduce power if the flashlight gets dangerously hot. See page 4 of the user manual for instructions on configuring ATR.”

That way, people who don’t read the warnings can’t learn how to endanger themselves. Poetic justice :slight_smile:

Thank you, I appreciate that :beer:

Hey, I had an idea. Tongue in cheek. How about:
“In case of survival emergency, we have designed your flashlight with the ability to fry eggs. Please avoid frying your hand by mistake.” :smiling_imp:

For a small, lightweight light, an li-ion battery can put out enough juice to heat it beyond the mass/dissipation limits.
The only way to stop it is to make a bigger light, or with a bunch of fins, or a fan, or just don’t run it that bright.
I’d rather have it available, even for a half minute, as long as it can limit itself if it gets too hot.

Several years ago high power filament lamp bulbs were restricted by federal law in Russia. We still can purchase them, but now they are sold as “infrared heater”.
You can make spacial label for such customers and sell flashlights as super modern portable hand heater.

I understand why it’s done, but the way hotrod lights are marketed creates a feedback loop and that’s why you have this problem. If there’s a way to squeeze every last drop of output from the flashlight, even if that output can only be maintained for 1 second of on-time before it starts to step down, that number will get the top headline because a huge number in the title is a good selling point.

Just look at the FW3A. Neal’s Gadgets advertises it as: TLF/BLF FW3A CREE XPL HI 2800lm EDC LED Flashlight Andúril UI. What good is 2800 lumens for 10 seconds, then rapidly decreasing output until it stabilizes at 900 lumens, 30 seconds on-time? It’s good for enthusiasts to impress each other, that’s it, but it’s worse than useless in real life use because when you feel you need that 2800 lumens you won’t get it long enough to do anything with. Even worse, the 900 or so lumens you actually can work with for more than a few seconds looks much dimmer after your eyes have been shocked by the turbo.

It doesn’t matter how many lumens can be achieved at 1 second on time in a pocket-size flashlight because without some sort of cooling system or breaking the laws of physics, pocket-sized lights have a hard thermal limit of around 1000-1500 sustainable lumens. In my opinion marketing has deceived people from understanding this simple truth.

I like output numbers to be reported by ANSI FL-1 standards: the final consumer product; in an integrating sphere; at 30 seconds on time; with the recommended battery. I don’t have a problem with a hidden turbo mode on a hot rod light, but marketing it as the top feature is going to give you this problem among others.

You got it. It’s fun. What’s the point in owning dozens of flashlights? Fun.

That’s enough of a reason, IMO.

simply tell them you can’t beat physics laws
if they don’t want dim lights they get hot and cant sustain max output a long time

I get that but the OP is evidently getting feedback from end users that they don’t like excess heat and near-instaneous stepdown. My post is in that context. The vast majority of people who buy flashlights are going to use them to illuminate darkness. For real world use an eye killing turbo that steps down to 30% output within 10 seconds is worse than useless and should either be removed or hidden. MOST IMPORTANTLY, it should not be advertised as the flashlight’s primary feature.