Iām sorry looking at my statement it really lacked clarity.
I want the thermal mass to sustain just running on high. The light heats very quickly on turbo and rather fast on high. I get about 28 seconds on turbo with a fresh battery but too hot to hold. A minute of running on high and itās rather hot to hold. For me the rapid loss of performance is letting it sit and cool before using again. Iām tempted if the light survives a few weeks of use to pot the electronics for water proofing and thermal relief of those tiny little tortured electronic bits. Iām only guessing, but I believe and extra ounce or two in the host and battery tube will bleed more heat out for longer more comfortable use. The battery tube is very thin.
Thanks for the very thorough review. We have updated the information on our website based on your review.
It would be really interesting to see what the performance of the EC65 would be on a 21700 battery that can deliver 30+ Amperes.
You can see similar information here as toobadorz tried a LISHEN LR2170SA which is the same as the yellow Liitokala lii-40A. This is a 15A continous rated battery. Itās voltage does not sag under the load and the light runs at 4,000 lumen for 1 minute when the thermal protection starts to ramp it down.
The only 30A continous rated 21700 I have seen is the Samsung 30T. I donāt think anyone has tried this combo yet.
I can now safely cross this light of my list. There are several smaller things that are, in my opinion, not well executed or thought out and keep me from buy this light, but the biggest issue is the temperature limit. Why did Acebeam set it at 75Ā°C ? That is just way too high. Sure it protects the electronics, but the temperature limit should be set according to the most temperature sensitive thing, the users hand. A limit of 50Ā°C or 55Ā°C (maybe 60Ā°C) would be better.
Furthermore most Li-Ion batteries have a maximum operating temperature of 60Ā°C, and bad things can happen when Li-Ion batteries get too hot.
To be fair, the high temperature limit is usually ok, since most of the time you will be holding the light in your hand and can just step it down manually when it feels too hot to touch (>50Ā°C). I rarely (never) leave a light unattended for hours.
Usually when I do runtime tests I will start the fan when the body reaches about 70Ā°C to protect the battery. This time I just wanted to see how hot the light would actually get.
Iām more disappointed about the single real turbo burst. Looks like toobadorzās new sample was able to do it four times before stepping down to the lower turbo level though. So thereās some variation between lights and batteries. Still, the visual difference between the maximum turbo and the next level down is non existent.
That is of course true, but I would prefer a temperature regulation I don't have to worry about. Perhaps I am spoiled by the excellent PID temperature regulation of Zebralights...
Acebeam should at least have bundled the light with a higher drain battery, or better yet improved the driver so that turbo mode works down to a lower voltage (lets say 3,3 V or perhaps even 3,0 V).
Bad mode spacing is a constant source of annoyance for me. The brightest modes are too close together, and the low modes are too far apart (unfortunately that is way too often the case).
On the EC65 turbo is only 3526/1784 = 1,98 times as bright as high (a difference that is simply too small and, as you say, barely visible), on the other hand low is more than 20 times as bright as firefly (and of course a 12 lm mode is really not deserving of the name "firefly").
On an unrelated note: maukka do you have a central place with links to all of your reviews? It would make finding them much easier in the jungle of threads on this forum, perhaps a central thread or your signature.
Noir, it sounds like your expectations are higher than current technology allows.
I hope that in the near future Lexel will have his high powered boost drivers working with NarsilM. Then you can set your own levels and your own temperature limits.
I think his Bistro UI works on them, but Iām not very familiar with Bistro.
I think building your own light is the only way youāll get it to your personal liking.
Hello maukka, your measurement indicates the max temperature of Mid is around 65Ā°C, but with my new EC65, I got only 43Ā°C (the max temperature measured around the side switch, during my whole Mid runtime test). My experiment is done under room temperature (25Ā°C), with no cooling.
That is pretty weird, or maybe I should measure the temperature around the head instead?
Thank you, maukka. Iām sure that my new EC65 can still be held after 30 mins of Mid. Its body tube was still under 42Ā°C then, and I did hold it to feel if itās too hot (it was not). So there are indeed some differences.
I don't think that is the case. A lower temperature limit is just a different value that is set in the firmware and has nothing to do with advancements in technology.
Technology is also not the limiting factor when it comes to improving the driver slightly. I am not talking about huge leaps like 5 A more in turbo or twice the efficiency, but small improvements that would allow the turbo to be sustained down to 3,3 V or maybe 3,0 V instead of just 3,5 V. Small things like for example double or shorted springs (lower voltage losses) would already help in this regard (for some reason Acebeam didn't bother doing this), or simply a slightly lower maximum (turbo) mode which can be sustained better.
As it is the EC65 (or rather its driver) is IMHO a bit too "on a knife's edge" (for lack of a better term).
Very true. If you want it done right, you have to do it yourself. One of the reasons I'm into modding .
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