Hey fellow torchbearers , just uploaded my video review to YouTube of this killer pocket rocket
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Thanks for the review! I have the 5000k variant and really like it.
SFT40 hi-cri 3000K is rated max 4A… only cold white low-cri have max 8A
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Who doesn’t care? The 3000k version has the same design as the cold version. Moreover, the 4A limitation makes practical sense only for 5000-5700k sft-40, because there is a spread of up to 1500-2000k depending on the power.
Huh? You I guess?
The phosphor is different. The 3000k variant is a 95 CRI LED which has a 4A max rating. I’d choose the 5A driver for the 3000k SFT-40. Running it at 8A uses a lot more power for not much additional output. It’s mostly heat.
The 70 CRI variants have no such limitation, they are rated to 8A.
SFT-40 3000K 8A vs 5A: 35% higher output for 60% higher power
SFT-40 6500K: 8A vs 5A: 37% higher output for 60% higher power
I would say that is within the margin of error, and definitely deep within sample-to-sample differences. Why is 37% worth it and 35% not?
Nichia 519A are rated to 2.2A, and yet flashlight people are barely running them <5A. So I would say running a SFT-40 WxH that is specced at 4A with 8A is not far fetched. Especially since it shows the identical lumen over current behavior as the WxE/WxS versions that are specced at 8A.
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Maybe we don’t really understand each other. For example, the 519Ar 9080 and r8000 models have the same design, while the power does not rest on different phosphors. As the power increases, the efficiency drops exactly the same in%, and the same thing happens here.
For example, the SFT-40 3000k in the 5A test gives ≈74% of the flux at 8A (1030/1400), and the SFT-40 6500K gives ≈72% (1820-5A versus 2520 at 8A), which is within the margin of error even between LEDs in the same strip. In other words, 8A on the 3000k version is more profitable to use than on 5000k, if only because the color temperature and hue remain the same over the entire range, with the same increase in lumens in%. And in the 5000k version, we get 4500k at low current, 5000k at 4A and 6500k at 8A.
I for some reason thought there was about a 20% difference in output in the case of the 3000k variant. My mistake.
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Might be different behavior between bins/batches… I based my calculation off koef3s tests, but you never know how different bins behave. Esp with Luminus often having Engineering Samples available that might be (significantly) different from the final production LEDs.
Pretty sure I inverted the Vf and lumens plots when I did the calculation.
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I’ve been using the short S6 with the sft40 3000k 5a linear with a 18350 Keep Power 1200mAh 10 amp battery as my primary EDC for over a year now. The amp draw currently at 100% is 5.6a. At 35% it is 2.0a.
I’m going to switch it up and get one with the 8a buck.
I’m going to try the new Keep Power 1600mAh 5 amp that has a pulse rating of 8 amps.
I guess I’m not up to speed on what that driver is doing when we’re not at 100%.
Any thoughts on that battery working for 20 to 40 seconds of 100% power? And any guesses as to what the amp draw will be at 35%? Most of the time when I’m running 100%, I can live with 10-20 second intervals. If I have to I’ll keep running the 10 amp battery but I’d really like the extra capacity.
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How hot does this light get and how quickly does it heat up.
I think that new keeppower 1600 mAh battery might be the same as the vapcell H16. The positive terminals look identical.
I’ll probably get both the 5a buck and 8a. And maybe both of those batteries. Then I’ll be able to test amperage of all three drivers at various battery voltages with three different batteries. With enough S6s in various locations I won’t have to worry about battery capacity.
Yeah,only cowards follow data sheets.
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I like data. I very much appreciate that you provided that link earlier in this thread. I have been blissfully unaware for over a year that I’ve been " potentially” exceeding the manufacturers published data by putting 5.6 amps into the spring which is going into the driver and is ending up at the led at an unknown amperage. I have some questions that I can’t find answers to so I’m going to gather some more data on my own. I promise the 8 amp driver will be used ”for off-road use only".
Long live Evel Knievel.
Edit. I appreciate all of the data that has been presented in this thread.
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Been using my 5a and 8a sft40 emitters in my s6 and c8 on almost constant turbo at my place of work for spotting animals for about 30 days straight now , zero issues
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Just bought this light in same configuration. Its truly a pocket rocket. Damn powerful.
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Hi all, I’m ordering a T6 with sft-25r and I was thinking to take the chance of this order from Convoy to buy something with a 3000k emitter.
S6 with SFT40 seems to be a recommended option, but I can’t decide between 5A and 8A.
I’m a newbie, so forgive me if it’s a stupid question, but… wouldn’t worth to get the 8A driver and use it at mid level for long run but get the extra power on hand for some short sporadic use at 100%?
What would be the benefit of the 5A?
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I have all three driver types currently available in the S6.
All with the same sft40-3000k.
5 amp linear
5 amp buck
8 amp buck
I did some amperage testing with quite a few different batteries but they were all charged to about 4.0 volts. This was on the 100% mode.
The 5 amp linear driver held turbo for almost a minute while staying pretty steady at about 5.5 amps. Then it starts dropping.
The 5 amp Buck driver starts off at 5 amps, at 30 seconds it’s down to 4.0 amps, at 60 seconds it’s down to 2.5 amps and still falling.
The 8-amp buck driver starts off at 6.6 amps and at the 2-minute mark it is down to 5.0 amps and starts dropping fast from there. It is much hotter than the others at one minute and pretty dang hot at 2 minutes.
I don’t know if all three have the same temperature sensors or if they’re all set at the same level.
The 8 amp Buck is brighter at all levels including the lowest moonlight which may be a good thing for some people. I never use that 0.1% but I want to have “battery check” so it is in the group that I use. On the 100% mode it’s only just barely detectable as far as being brighter at first but then you can maintain turbo longer.
I’ve carried the 5 amp linear with the short tube for 2 years now as my primary EDC. I probably will give the others a try for a month each to see if I notice much difference in daily use.
I would say if you want that extended turbo frequently with the 8a then you need an 18650.
I can get through most days easily because I carry a secondary EDC. Although sometimes I can go many days without having to recharge.
I mostly use 35% and 100% for various intervals.
Maybe after a few more months I can pick a favorite of the three. It’s good to have options.
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