Fenix TK30 has boost circuit?

[dudu84]

Two nights ago, after I did a break-in on my 2 new Black & Red TF2400mAh 18650s with the TK30, I realized the lens was a bit foggy, probably because I tried to cool it with a fan when it was pretty warm. Like any Tk30 lover here, I can't live with a foggy lens :mad:, so I ended up opening the head to clear that up, also to mod it with a 5A MC-E K-bin from Cutter.

Here's what I found: the MC-E is mounted in series on a 20mm star, meaning that the circuit needs to boost the voltage to ~13.6V on turbo mode, from ~7.4V of the 2x 18650. This is probably why when we feed TK30 with 4x fresh CR123A cells, the low mode is gone. Also, we basically can't mod it with SST-50 due to different Vf.

I also measured the output (in ceiling-bounce test) before and after the mod to see if TK30 is equipped with MC-E M-bin or K-bin by Fenix.
The result: my 5A MC-E K-bin TK30 lost to the original TK30 by ~5%, which doesn't tell much.

However, if I have to make a guess, I'd say it's likely that TK30 will come with MC-E K-bin (I bought it maybe 6 months ago). Nevertheless, I am now extremely happy with the NW TK30 :hitit:

Thanks for reading

 

[csshih]

trying to think on that one....
looking at the board, how can you tell it's wired in series?

 

[dudu84]

trying to think on that one....
looking at the board, how can you tell it's wired in series?

Trust me, I did it the hard way: I used my MC-E wired in parallel first (also from Cutter) and the light was EXTREMELY bright and hot (now I'm surprised the LED didn't pop at that voltage) and all the modes were gone. I ordered the MC-E wired in series from Cutter the same day I opened the head and now it works perfectly :]

 

[AnAppleSnail]

Isn't the tailcap draw 2.5-3 amps or so? that sounds like 4 750 mA die driven in parallel.:duh2:

Edit: See below. I'm dumb.

 

[dudu84]

Isn't the tailcap draw 2.5-3 amps or so? that sounds like 4 750 mA die driven in parallel.:duh2:

The current at the tailcap doesn't tell anything about the voltage going through the LED, and I highly doubt the light draws 2.5-3A on 2x18650 because 2x 2400mAh 18650 lasts 1h46' on turbo, so current draw is ~1.36A

 

[AnAppleSnail]

The current at the tailcap doesn't tell anything about the voltage going through the LED, and I highly doubt the light draws 2.5-3A on 2x18650 because 2x 2400mAh 18650 lasts 1h46' on turbo, so current draw is ~1.36A

Ah, you're right and I'm silly. thanks.

 

[HKJ]

Isn't the tailcap draw 2.5-3 amps or so? that sounds like 4 750 mA die driven in parallel.:duh2:

The tailcap draw depends on the voltage and for any light with a buck or boost regulator the led current is different from the tailcap current (Except when Vf=Vbatt).

 

[dudu84]

Ah, you're right and I'm silly. thanks.

I always thought Fenix TK30/40 have buck circuits as TK10/11/12 P3D etc as well, leading to the guess the MC-E in TK30 is driven in parallel; I even thought of ordering a SST-50 for it lol

 

[TyJo]

I am a complete newb about modding lights. How did you open the head? Could a newb like myself put a different emitter (not another MCE), in this light, like an XML or something brighter then the MCE?
Thanks.

 

[dudu84]

I am a complete newb about modding lights. How did you open the head? Could a newb like myself put a different emitter (not another MCE), in this light, like an XML or something brighter then the MCE?
Thanks.

Opening the head won't be difficult, just use a hair dryer on high mode, pointing it at the fins for 3-5 mins then you should be able to slowly unscrew the head. Make sure you use something that proves good grip like a mouse pad (rubber face) that also insulate the heat, because it will get HOT.

However, I'm afraid putting an XM-L LED in there won't do any good. XM-L has low Vf and the light will go into direct drive mode when the battery voltage is higher than thh LED Vf, meaning you will lose all modes, it will be a single-mode light :/

 

[TyJo]

Opening the head won't be difficult, just use a hair dryer on high mode, pointing it at the fins for 3-5 mins then you should be able to slowly unscrew the head. Make sure you use something that proves good grip like a mouse pad (rubber face) that also insulate the heat, because it will get HOT.

However, I'm afraid putting an XM-L LED in there won't do any good. XM-L has low Vf and the light will go into direct drive mode when the battery voltage is higher than thh LED Vf, meaning you will lose all modes, it will be a single-mode light :/

I probably will leave it alone, but I was wondering how difficult it would be to put a warm MC-E in the TK30? I posted a thread here in the modified flashlights forum.

 

[Walterk]

However, I'm afraid putting an XM-L LED in there won't do any good. XM-L has low Vf and the light will go into direct drive mode when the battery voltage is higher than thh LED Vf, meaning you will lose all modes, it will be a single-mode light :/

I know, I tried and it worked like you said, but not with very high brightness.
Took me some time to understand the MCE was in series.

 

[dudu84]

I probably will leave it alone, but I was wondering how difficult it would be to put a warm MC-E in the TK30? I posted a thread here in the modified flashlights forum.

Once you get the head opened, swapping the LED is very simple.
-The LED star is "kind of" glued down by the thermal grease, you can pry it up easily with a small screw driver (use a strong one to be safe)
-Remember to clean up the thermal grease and put a new layer in there, I'd use something like Alumina Adhesive as it provides stickiness but not that unnecessarily strong.
-Solder the new LED in there and you are good to go. ***make sure you order a MC-E in SERIES, not parallel***. I used the 20mm star from Cutter, you might need to trim down the edges a little to make it fit
***Don't forget to put the transparent plastic back, it's to electrically insulate the reflector from the LED***

Good luck!

 

[dudu84]

I know, I tried and it worked like you said, but not with very high brightness.
Took me some time to understand the MCE was in series.

Is the XM-L well focused in the MC-E reflector?
I think XR-E, XP-E and MC-E have the best NW tints (love the 5A!), XP-G NW (and possibly the XM-L too) tints are very good, but not that great

 

[TyJo]

Once you get the head opened, swapping the LED is very simple.
-The LED star is "kind of" glued down by the thermal grease, you can pry it up easily with a small screw driver (use a strong one to be safe)
-Remember to clean up the thermal grease and put a new layer in there, I'd use something like Alumina Adhesive as it provides stickiness but not that unnecessarily strong.
-Solder the new LED in there and you are good to go. ***make sure you order a MC-E in SERIES, not parallel***. I used the 20mm star from Cutter, you might need to trim down the edges a little to make it fit
***Don't forget to put the transparent plastic back, it's to electrically insulate the reflector from the LED***

Good luck!

Thanks for the advice, especially putting the transparent plastic back.

 

[cdrake261]

Why not replace the driver and the LED?

 

[TyJo]

Why not replace the driver and the LED?

I didn't because that would be too advanced for me, I just wanted to do a simple emitter swap. The warm MCE is great, I love the tint.

 

[cdrake261]

I wonder if anybody else tried it... I heard it said that xm-l emitters work will with mc-e reflectors.

 

[ergotelis]

I wonder if anybody else tried it... I heard it said that xm-l emitters work will with mc-e reflectors.

Modded a Tk30, removed led+circuit, then added a new 3amp buck circuit(old one was a boost, the mc-e was in series). The flashlight has now 27000 lux(was about ~14,000) and the output from 480 OTF went up to 850 OTF with a good U2 led! It focuses just fine, excellent throw+spill.
Of course, we have lost the twisty mode selection.

 

[cdrake261]

Modded a Tk30, removed led+circuit, then added a new 3amp buck circuit(old one was a boost, the mc-e was in series). The flashlight has now 27000 lux(was about ~14,000) and the output from 480 OTF went up to 850 OTF with a good U2 led! It focuses just fine, excellent throw+spill.
Of course, we have lost the twisty mode selection.

Have a thread on it? Or at least where and what driver you used?