Question about Fenix TK20 Current Draw

I just received a used Fenix TK20 today. I measured the current draw between the negative battery terminal and the body of the light with both new and used batteries. With fresh alkalines, the current measured 1500mA. With used batteries measuring 1.43v unloaded, the current draw was 2600mA. Both of these numbers seem high to me.

If anyone has a Fenix TK20, would you please measure your light to see if my light seems to be working properly? Thanks!

My TK20 draws around 1.5A on fresh alkies as well as Nimh on high. Since it's a regulated boost circuit, the current draw will get higher as the voltage in the cells drop.

Does yours make a high pitched noise on high? Mine is so irritating that I rarely use the light...

As wingnut stated, that's just the boost circuit doing it's thing. It will draw more current as the batteries' voltage goes down to keep the same power to the LED. 1500 mA draw at the start sounds normal.

Wingnut...Thanks for your input. I've never had a 2AA light pull that much current before. The 2600mA in particular makes me nervous. One good thing, the light doesn't whine at all. I believe it's the choke in the regulation circuit that makes the noise.

FlashCrazy said:

As wingnut stated, that's just the boost circuit doing it's thing. It will draw more current as the batteries' voltage goes down to keep the same power to the LED. 1500 mA draw at the start sounds normal.

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Thanks FlashCrazy!

Mine whines sometimes, I think its a battery thing :shrug:

nikon said:

Wingnut...Thanks for your input. I've never has a 2AA light pull that much current before. The 2600mA in particular makes me nervous. One good thing, the light doesn't whine at all. I believe it's the choke in the regulation circuit that does makes the noise.

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Your welcome!
I'll trade you TK20's!!! Although mine doesn't whine with alkies, just nimh and L91's, the two types I prefer to use in the light!!

wingnut86 said:

Your welcome!
I'll trade you TK20's!!! Although mine doesn't whine with alkies, just nimh and L91's, the two types I prefer to use in the light!!

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Never used alkalines but will whine some on high with NiMH. Nothing on med and often just use that anyways. Not a big problem for me even on high but just the same I would prefer this didn't happen. I have read someplace that Fenix doesn't make the TK20 anymore? Wonder if this is true and what if anything would replace it.

Mine draws ~1.5A.
Whines with most batteries, operating temperature affects it too.

Woods Walker, TK21?

Egsise said:

Mine draws ~1.5A.
Whines with most batteries, operating temperature affects it too.

Woods Walker, TK21?

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I hope they make something like it. It lives in the BOB as like the thick build. Glad none whine on med. The high does this but not that bad and sometimes less so. Not sure why this happens but heard other lights do the same thing. There is a buzz on my S2/LOD but again not so bad. I wanted to get a replacement clicky just incase for the BOB but now the only dealer that had these listed (T-switch) is all out.

Please excuse my antipodean ignorance but what is "the BOB"?

JaguarDave-in-Oz said:

Please excuse my antipodean ignorance but what is "the BOB"?

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Bug Out Bag, aka 72-hour kit.

Got it, thanks for that, I thought it must have been a name you gave your truck or something but I'm a bit slow on the uptake at times.

I have a "flood bag" cos we get floods and I knew of "bail out" bags, now I've something new to add to my vocabulary.

Egsise said:

Woods Walker, TK21?

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paintballdad said:

They had a couple other prototypes at MattK's party. One of them is the TK21, it's a little slimmer than the TK20 and the rubber grip seems better molded to the body. Has an XP-G and seems to be in neutral white.

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Oh what a coincidence.

Mines also whines, but ever since I tightned the head to a tight thats not too loose but not to tight never whines. The only time it whines is when I untighten the head about 1/10 of a mm.

like I said, it doesn't whine when tight, but when i turn it on, it is silent for about 2 seconds, then this sound similar to gas being released is emited. you can barely hear it. And it is brighter by about 10 more lumens than when it is on my "whine mode".

Just saying, great light, you won't even notice the whine when acutally using the light, only if you have it around 3 feet away and everything is VERY quiet.