Fenix TK40 part 3
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richardcpf
Flashlight Enthusiast
- Joined
- May 23, 2008
- Messages
- 1,281
Re: TK40 photo
The head looks "weak" for a TK series light...
SEE IT IN ACTION!!
2:30
http://www.youtube.com/watch?gl=HK&hl=zh-TW&v=x8QVH1Vgl2k
"630 lumens!"
The head looks "weak" for a TK series light...
SEE IT IN ACTION!!
2:30http://www.youtube.com/watch?gl=HK&hl=zh-TW&v=x8QVH1Vgl2k
"630 lumens!"
Destroid Monster
Newly Enlightened
According to the manual, lockout is recommended due to the parasitic drain but to be fair I've never really get around to prove the drain but the sensitive clicky is quite a pain & 3 full turn for a lockout is pretty inconvenient.
For sharing, I'm using the same Tatanka len pouch $10 (pix shown with my Porky L6-M6 setup)
jzmtl
Flashlight Enthusiast
Well all these talk of drain, can anyone just take a multimeter and complete the circuit and see if there is one or how much drain there is?
flasherByNight
Enlightened
- Joined
- Oct 17, 2008
- Messages
- 465
might as well pimp my own thread...
I'm trying to keep a summarization of all the good information throughout these threads. So if you don't want to read part 1&2
Fenix TK40 Informational Roundup (56k Killer!)https://www.candlepowerforums.com/threads/228421
I'm trying to keep a summarization of all the good information throughout these threads. So if you don't want to read part 1&2
Fenix TK40 Informational Roundup (56k Killer!)https://www.candlepowerforums.com/threads/228421
bodhran
Enlightened
I saw and I like. Thanksmight as well pimp my own thread...
I'm trying to keep a summarization of all the good information throughout these threads. So if you don't want to read part 1&2
Fenix TK40 Informational Roundup (56k Killer!)https://www.candlepowerforums.com/threads/228421
DM51
Flashaholic
flasherByNight, your "Roundup" thread is a good idea. Please let me know if there are any other posts you would like moved or copied into it.
I hope members will respect your wish that they do not post in it - I've already deleted 1 superfluous post there.
To all: discussion belongs here in this thread, so please do not post in the Roundup one.
I hope members will respect your wish that they do not post in it - I've already deleted 1 superfluous post there.
To all: discussion belongs here in this thread, so please do not post in the Roundup one.
flasherByNight
Enlightened
- Joined
- Oct 17, 2008
- Messages
- 465
Just a suggestion, there's sometimes a bad tendency to read only the first and last post in a thread. Maybe add my link to the first post? Just a thought... (I'm guilty of this too occasionally )
*and like I said, please PM me for additional suggestions...I'm sure I've missed alot: some I'm just not sure how it ought to be added
(seriously image intensive fyi)
)*and like I said, please PM me for additional suggestions...I'm sure I've missed alot: some I'm just not sure how it ought to be added
(seriously image intensive fyi)
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burntoshine
Enlightened
qip, it clicked on accidentally. i thought i might have cooked something in the light or lessened the life of the led. i wrote fenix to see what they had to say. i thought they might not honor the warranty if they knew it was stuffed in a backpack on turbo for a few hours, but i figure honesty is the best policy and i was willing to take the chance for peace of mind.
fenix wrote:
"Due to the overheat sensor in the light i think you are fine. If something like that was really bad for the led it would have gone into thermal runaway and it wouldn't be nearly as bright now. You dodged a bullet and are going to be just fine. In the future you may want to unscrew the back of the light a bit to lock it out."
i wasn't thinking when i threw the light in there. live and learn.
thought everyone might like to know, the tk40 can take a heating and still keep on lighting.
fenix wrote:
"Due to the overheat sensor in the light i think you are fine. If something like that was really bad for the led it would have gone into thermal runaway and it wouldn't be nearly as bright now. You dodged a bullet and are going to be just fine. In the future you may want to unscrew the back of the light a bit to lock it out."
i wasn't thinking when i threw the light in there. live and learn.
thought everyone might like to know, the tk40 can take a heating and still keep on lighting.
bodhran
Enlightened
That's good to know since I'm not alway good about locking out my lights.
Twinkle-Plank
Newly Enlightened
Just wondering does the TK40 have reverse polarity protection?
Jackal-Head
Newly Enlightened
Alkalines and maximum power
Is is bad regulation or just the inherent limitations of alkaline battery chemistry? There's a limit to how much power you can obtain from a battery. If the device has a very low resistance, battery power is maximized, but almost all of the power is wasted in the battery, causing it to heat up (this is true regardless of battery chemistry). With very high device resistance, less power is wasted, but the total power from the battery decreases, so again, the usable power will be low. There's an optimum somewhere in between, and according to my simple calculations, the unsurprising result is: This maximum usable power is obtained if the resistance of the device is equal to the battery's internal resistance. In this case, we can calculate the maximum device power as U^2 / 4Rb, where U is the unloaded voltage and Rb the battery's internal resistance.
I applied this formula to some publicly available information from Duracell, in particular on the CopperTop AAs (MN1500). This is the result (discharge percentage, approximate maximum device power). Note that for a TK40 in turbo mode, about 1.3W per battery are required. A more accurate estimation could be obtained by taking the 2P4S setup into account.
0% - 7W
10% - 4W
20% - 3W
30% - 2.5W
40% - 1.8W
50% - 1.6W
60% - 1.4W
70% - 1.2W
80% - 1W
This indicates that CopperTops which have been discharged less than 35% should be easily capable of driving the TK40 in turbo mode at full lumens. If the batteries have been discharged 35% to at most 65%, it should still be possible though the efficiency will noticeably decrease, speeding up the discharge rate. Below 35% remaining charge (65%+ discharged), there's no way the TK40 could continue at full power even if the regulation were perfect, which of course it isn't. I also looked at the Procell and Ultra data, but didn't analyze it further because both battery types have better characteristics than the CopperTop, so you should see a performance increase over the CopperTops in any case.
The bottom line is: Duracell CopperTops should absolutely be able to power the TK40 turbo until they have somewhat less than 50% remaining charge. Being an NiMH advocate, I'm pleasantly surprised by this observation, however I do have to note that run-of-the-mill alkaline batteries from your local discount store probably will not keep up with these numbers. For instance, if you assume that a cheap battery may have twice the internal resistance (same voltage), this means they can also deliver only one half the power. In this case, even after only a 25% discharge, the power may be insufficient for turbo mode. In addition, they will discharge less efficiently, so it will take less time until the 25% mark is hit.
HKJ said:
Is is bad regulation or just the inherent limitations of alkaline battery chemistry? There's a limit to how much power you can obtain from a battery. If the device has a very low resistance, battery power is maximized, but almost all of the power is wasted in the battery, causing it to heat up (this is true regardless of battery chemistry). With very high device resistance, less power is wasted, but the total power from the battery decreases, so again, the usable power will be low. There's an optimum somewhere in between, and according to my simple calculations, the unsurprising result is: This maximum usable power is obtained if the resistance of the device is equal to the battery's internal resistance. In this case, we can calculate the maximum device power as U^2 / 4Rb, where U is the unloaded voltage and Rb the battery's internal resistance.
I applied this formula to some publicly available information from Duracell, in particular on the CopperTop AAs (MN1500). This is the result (discharge percentage, approximate maximum device power). Note that for a TK40 in turbo mode, about 1.3W per battery are required. A more accurate estimation could be obtained by taking the 2P4S setup into account.
0% - 7W
10% - 4W
20% - 3W
30% - 2.5W
40% - 1.8W
50% - 1.6W
60% - 1.4W
70% - 1.2W
80% - 1W
This indicates that CopperTops which have been discharged less than 35% should be easily capable of driving the TK40 in turbo mode at full lumens. If the batteries have been discharged 35% to at most 65%, it should still be possible though the efficiency will noticeably decrease, speeding up the discharge rate. Below 35% remaining charge (65%+ discharged), there's no way the TK40 could continue at full power even if the regulation were perfect, which of course it isn't. I also looked at the Procell and Ultra data, but didn't analyze it further because both battery types have better characteristics than the CopperTop, so you should see a performance increase over the CopperTops in any case.
The bottom line is: Duracell CopperTops should absolutely be able to power the TK40 turbo until they have somewhat less than 50% remaining charge. Being an NiMH advocate, I'm pleasantly surprised by this observation, however I do have to note that run-of-the-mill alkaline batteries from your local discount store probably will not keep up with these numbers. For instance, if you assume that a cheap battery may have twice the internal resistance (same voltage), this means they can also deliver only one half the power. In this case, even after only a 25% discharge, the power may be insufficient for turbo mode. In addition, they will discharge less efficiently, so it will take less time until the 25% mark is hit.
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Glock27
Enlightened
I wouldn't think so. No way for the carrier to make contact with the pill if you put in backwards. Carrier contacts would short on tailcap installation too.
G27
I received my TK40 today and I very happy with it. All the guys around the office (got delivered to my workplace) that I showed it to were also very impressed by how bright it is. Feels very well built and solid and absolutely love the little 'hot' warning label on the head. I think that's brilliant.
Haven't had much of a play with it outside, but it does throw a beam of light pretty far. Hopefully I should have some more time over the next few nights to use it some more outside in the dark.
Inside a room tailstanding on turbo mode lit the room up a little bit brighter then the 60W CFL equivalent (on a bare batten holder - no light shade) on the ceiling. How much brighter is hard to say as I have no measuring equipment.
Overall I'm very happy with the TK40. The only real complaint that I have is, like others have mentioned, is the case that it comes with. Very flimsy hinges, the little carry handles want to pop off and mine doesn't really seem close properly either, it's very tight to close. I'll end up getting a custom pouch for the TK40 made so that I can mount it onto my camelbak anyway, so even if the included fenix case was well built I probably wouldn't have used it so it's not that big of a complaint to me. The UI isn't bad either, just takes some getting used to, but I do appreciate not having to flick through any of the flash modes when switching through brightness levels.
Haven't had much of a play with it outside, but it does throw a beam of light pretty far. Hopefully I should have some more time over the next few nights to use it some more outside in the dark.
Inside a room tailstanding on turbo mode lit the room up a little bit brighter then the 60W CFL equivalent (on a bare batten holder - no light shade) on the ceiling. How much brighter is hard to say as I have no measuring equipment.
Overall I'm very happy with the TK40. The only real complaint that I have is, like others have mentioned, is the case that it comes with. Very flimsy hinges, the little carry handles want to pop off and mine doesn't really seem close properly either, it's very tight to close. I'll end up getting a custom pouch for the TK40 made so that I can mount it onto my camelbak anyway, so even if the included fenix case was well built I probably wouldn't have used it so it's not that big of a complaint to me. The UI isn't bad either, just takes some getting used to, but I do appreciate not having to flick through any of the flash modes when switching through brightness levels.
I just got my TK40 also. I'm very impressed with this light but I'm fairly new to this forum and to flash light tech.
I think I'll use this light alot, therefore, over the counter AA Copper Top type batteries will soon bleed my wallet dry.
What rechargeable batteries does everyone recommend for this light and what charger will charge 8 AA batteries at once?
thanks for the replies,
newbie with great new tool.....:twothumbs
I think I'll use this light alot, therefore, over the counter AA Copper Top type batteries will soon bleed my wallet dry.
What rechargeable batteries does everyone recommend for this light and what charger will charge 8 AA batteries at once?
thanks for the replies,
newbie with great new tool.....:twothumbs
Congrats on your new toy. I am highly impressed by the Tk40 and the overall quality of the package minus the little flimsy box it came with. :sick2:
I am a huge fan of Sanyo Eneloop batteries. I have about 16 AA´s for my lights, gps etc. I highly recommend these for they are IMO the best NIMH batteries on the market. Regarding the charger I have two Eneloop chargers that take 4 batteries each.
Glock27
Enlightened
I'm using Sanyo 2700's for longest runtime. I will use Eneloops for long term storage in ready condition.
Maha makes 2 versions of an 8*AA charger each with different charge rates. I use a pair of Maha C9000s. I like the data that the C9000 gives you......along with settable refresh, cycle and analyze functions.
G27
Maha makes 2 versions of an 8*AA charger each with different charge rates. I use a pair of Maha C9000s. I like the data that the C9000 gives you......along with settable refresh, cycle and analyze functions.
G27
bhuber
Newly Enlightened
Really there is, just turn the head or tail cap about 3 turns to lock it out. The instructions state this. I prefer to lock out the tail cap rather than the head, but either will work. Mine is locked out now to prevent battery drain. I also do this with my TK10 when its in it's in a bag so the button doesn't get pressed on momentary on. I got to briefly go out last night and shine it around for a few minutes, I'm blown away by the throw. Enjoy it!
north_star
Newly Enlightened
I'm useing for a pouch for my TK40 is a crown royal pouch nice and soft
