Thank you, that helps me with my battery choices. 15A at 10,000 lumens seems low. the 40t should do it but I will try the 30t and Molicel as well to see if there is a difference.
I’m fascinated by the FW21 Pro to the point I’ve nearly purchased it more than once, but I’ve got my doubts that it will hit the claimed 10k lumens on turbo:
Assuming 3V XHP50.2, maximum rated current is 6A which just cracks 180% nominal lumens with top-binned emitters hitting 1328 lumens at 25C or a still-optimistic 1200 lumens at 85C so at max current you’re looking at 2160 lumens; Some hazy - and probably far too generous with diminishing returns and all that - math dividing 2160 by 6A suggests 360 lm/A thus you’re looking at ~9.26A to hit 3333 lumens per emitter or 27.8A
illumn ‘helpfully’ suggests NCR18650GA (10A peak discharge) and INR18650-35E (8A peak discharge) as compatible 18650s which probably aren’t going to do much for turbo, although they do recommend the INR21700-30T in 21700 which will push 35A
However, the review indicates that output is closer to 7000 lumens so the current situation changes:
2333 lumens - 2160 lumens at 6A = 173 lumens / 360 lumens per amp = 480mA deficit so peak current demand is 6.48A x3 = 19.44A … a much more comfortable overdrive level
20A is within the realms of more humble cells such as the Samsung 25R which I have many of
Thus … is this a real bump from the D4 / D4S / FW3A in terms of output - either at turbo or at a brightness level the light can actually sustain?
My Bangggood orders take about 30 days to reach me so I will not have my FW21 Pro till the 20th of this month. I do not have the equipment to test the light but would like to know the Actual numbers it will produce. Hoping someone here with the equipment who owns one will test it. I purchased it after watching a few videos on You Tube up against the NSX3A which I own. The FW21 looked a bit brighter then the NSX3A but with slightly less throw. It did surprisingly well against the Acebeam X10 and the Fenix Lr35R as far as output goes. Fenix LR35R - Nightwatch NSX3 NS53A - Lumintop FW21 Pro - Acebeam X10 comparison - YouTube
I have an integrating sphere made with pvc tubes and a luxmeter
None of my lights reach the Claimed lumens and throw, but I measure the FW21 at 10600lm. It’s the only light I’ve tested that measures over the claimed lumens, that must be something
Guys, I did my best at measuring its output but my equipment is rather simple compared to some integrated spheres, but by far it was measuring accurately. My Wizard Nichia output was accurate, compared SKV89, the same thing with FW3A. But maybe it cant handle that high brightness well… I will try again, but I’m not gonna argue - you may be right, I may be wrong
Lacking detailed knowledge of your apparatus and lumen measurement theory I cannot much criticize your respective measurements. My root confusion is that >150% overdrive appears to be required to hit the manufacturer’s claimed 10k lumens - something that’s likely possible for brief periods but seems like it would strain the chain of components in the light.
I do suppose that perceived brightness is likely a step up over the FW3A’s nominal peak turbo output of 2800 lumens being more than double at the lower end of ~7000 lumens. The case vs the D4/D4S isn’t as clear with its purported peak output of 4300 lumens and thus not even double. In both cases, a casual assessment of that turbo output suggests that no overdrive is necessary . Of course, with markedly different LED characteristics and optics, the difference muddies appreciably and the main difference may well be floody reflector vs TIR.
My FW21 Pro showed up today and it is nice. My only gripe is the finish. It is very slippery with no texture for gripping. It is a very SMALL flashlight lol. When I put it in the palm of my hand and make a fist it disappears. The fit and finish is great, the switch is a little to soft for my liking but over all a very nice torch. It gets hot fast in turbo! lol. I am able to hold it threw its cycle but just barely and it stays hot for a while. The top of the ramp is just about perfect for a torch this size. It throws a wall of light out extremely well. The strobe mode it intense lol and should have a rating of 10 on the Richter scale, Extraordinary! Something about the three emitter strobe patterns, awesome! This is definitely a torch I will not be double tapping in turbo mode unless I need a small nuclear melt down or to fry some bacon. Very happy with my purchase and the price point.
It could use some grip texture or somethin, i like how olight has those black rubber pads on the seeker 2 pro… almost impossible to slip with that light in hand. but i feel fw21pro is ok to hold thanks to its weigth with the battery, but can understand some wanted maybe a little better texture orso…
Hi, I didn’t say I had changed the maximum ramp level to 133 to get something close to the 2,000 lumens held, I feel the misunderstanding.
My FW21 Pro gives about 1350 lumens with a 40T at the original ramp maximum and about 850 with a 50E.
The 2.8A stabilized mode, as you announced, is at level 130.
On turbo the maximum lumens I get at the start with a 40T to 4.18v is 9,200.
In the maximum stabilized 8x 7135 mode that is applied at level 130 the flashlight consumes 2.8A.
In turbo I measured the intensity with an amperimetric clamp and 10awg cable and part rigid filament because of the difficulty of the double tube of the FW21 Pro and got 23A, although I think they were limited by the measuring circuit that I used and that with the flashlight mounted consumption is in the range of 28A
Regarding the D4 the FW21Pro is able to maintain many more lumens, without a doubt, in fact only with the cooling that provides keeping it in hand is able to keep indefinitely the 2.8A mode that in mine represents about 1250 lumens
There you have the graph at 2.8A, the lumens are 1250.
The ambient temperature is 30 degrees, so I have brought it a small usb fan that has an effect similar to carrying the flashlight in your hand.
The flashlight is set to 75 degrees maximum temperature limit, but even so from 60 degrees it begins to regulate and hardly goes above 65, usually floating between 60 and 65 degrees.
If anyone is interested, I can record a thermal image with a flir of that runtime and upload it in 10x accelerated time lapse
This flashlight was designed for a high amp cell like the 30T so why use a 50E at 10amps? Are you just going for max run times, it is a hot rod flashlight and not meant for a bike. Just confused on your cell choice for testing its 10,000 lumen rating. That’s what we were talking about I believe.
You’re right. I have three 40Ts to use with it, but to test runtime and if I decide to use it on the mountain bike to the maximum that I have set, about 3,000 lumens, 140, I also use the 50E.
Think that on the bike and at night the flashlight cools much more than we can think and is capable of many lumens without overheating
Now that’s impressive! I was thinking at best around 7500LM to 8000LM. Did you use the 30T cell?