If neither acebeam or olight can manage to produce lights with active cooling then it seems something is wrong no? because waterproof fans etc exist so i dont get it ?
I doubt they can go fanless, even the x9r if i run for almost 3m it gets quite hot at the head, so that much more lumens is almost worthless if they go full passive since that light will produce more then what 220W of power ?
Maybe they can bundle one of those misting fans with each light. Put some ice in the bottle and every time it gets too hot you just spray it a couple times.
Edit: That was a joke, in case anyone thinks that was serious.
But i dont get it, acebeam showed earlier the prototype with 3 fans, same did olight so its weird if also they now ditched the fan design, the light will cost alot more then x9r so for that much lumens i think active cooling is a must if they want longer runtimes on max then a few min …
Not at all. Based on my calculations, it just might be able to do 40k lumens continuously. It’s kind of at the limit.
Now 30k continous is definitely doable.
So if 40k lumen is borderline, I could definitely see it doing 40k for at least 5 to 10 minutes, then step down to 30k for the rest of the batteries life.
Even this is a huge step up from the 7k continous lights we currently have.
But once the batteries drop half their capacity, the volt isnt too low too keep up that much lumens? im skeptical… my olight x9r i cant do 2 highest modes once battery shows 4 bars out of 8 left… ?
Considering the XHP70.2 thermal resistance of 0.9C°/W and a max Tj operating temperature of 150°C, with 29W input, and 23°C ambient, this would mean the heatsink could be allowed to rise 100°C above ambient, yes? Though the LED output would be reduced to 85% of the rated maximum at this Tj. To maintain 85°C Tj, the heatsink would only be allowed to rise 36°C? This is probably overly simplistic. Will dig into the requisite math more later.
With the very basic understanding I have of this matter, you are not wrong.
I think that with 3 fans it would be possible to keep the heatsink at a decent temperature, let’s say 100°C. Even if the fans can’t handle it the time it runs on full power is extended. So it’s a win nevertheless.
The lack of surface area to dissipate heat will make the fans less useful, and the few fins on the X70 are pretty thick based on the picture. If they used a CPU style heatsink it would be a whole different story.
The problem with acebeam is they insist on using small fans with tiny propellers with relatively low CFM, even 3 of them can’t compare to a properly sized fan.
I think this would be a more effective solution: fresh air is drawn from the back and exits through the emitter side (sorry for the quick paint job)
Looking back at my older posts in this thread, I think Acebeam was shooting for 30 minutes at 40k lumen. Then it would have to reduce output. Does anyone remember Acebeam saying this?