I need some help figuring out the throw of these lights.

Thanks a lot scaru! :) Stay tuned for an updated 10m test with all of the lights using NCR18650PD batteries at 4.18-4.20v. The first test was not very controlled so this one will be much better. I just have to top off some batteries quick.

So are those numbers pretty believable? Should any of them be higher or lower that you know of? I ask because my eyes are getting to used to these monsters. To me they all seem dim. (Not good!!! )


My TN31 got 127k before dedoming and my BTU shocker got about 116k w/o the a/r lens before getting worked over by Tom E. My TK75 is right at 95k and it is stock. I do believe that these are pretty typical numbers for these lights. The shocker was about 10k lower than my brothers though. I am sure they vary a bit,

Ok so it would appear that your meter reads high? I'm not sure if I have every seen anyone get 127k from a TN31 or no?

Joe - did Wayne say specifically what the new amp readings are for the TK75 and Shocker? The amps will tell you a great deal. If you could, it's easy to do the equivalent of a tailcap amp measurements on the Shocker, if you have heavy gauge DMM leads - simply set your DMM for DC amps and jump across the switch - one lead on one side of the switch, the other on the other side, effectively jumpering the switch. That amp reading will tell you a lot of what's going on.

Weird bout the HD2010 - I've done quite a few, many others have, and it's pretty well published here on BLF. My best way is to use a Nangj driver up at 4.2-4.5A, press fit in a brass ring into the pill and mount the driver to the brass ring. I usually dremel down the pill a bit to get a good press fit of the brass adapter ring. My HD2010 is 4.2A and I can measure 4.3A on the better 26650 cells. You get high lumens and great throw. I just measured mine at 1,459 lumens at 30 secs, and 97 kcd throw for an XM-L2 U2 on a SinkPAD with dome. It does about 200 kcd de-domed.

Wayne didn't tell me what the new amps were.

I have DMM but it's not a very good one. I have never tested amps on shorty 3x18650 and 4x18650 lights because I didn't know how to.

Measured a few in that range with XML U2, the last one you shipped to me - a XM-L2 U2, I measured at 146 kcd, which makes sense. These #'s have been measured by others in the same ranges.

hhmm - did he tell you what driver he used in the Shocker? We could tell by that. Do you know if he swapped out the carrier springs or copper braid them? Sorry for all the Q's - just wondering what he did, because that would tell me what kind of capability the light will have.

Oh nice, so it looks like my meter is really low than. That make me feel a little better.

Do you know if the emitters deteriorate and lose perforance drastically as they age. The stock TN31 XM-L2 I have get used about 2 minutes every other day. About 50 minutes total. Is that enough to reduce the performance noticeably from brand new?

Joe, that DDM is decent. About the same one I use. Sure there are better ones, but you could do a lot worse. You could upgrade your leads to custom heavy gauge wire to get better readings at high amperage.
I’ve tested several XML U2’s TN31’s ranging anywhere from the 115-127K range. Not sure what’s going on with the shocker. Sounds like domed xml2 type BTU numbers. But increase your distance and retest if possible.


He said it was the same one you used. But there are two models on IOS that look similar:
http://intl-outdoor.com/xml-multicell-circuit-board-3a-55126v-p-361.html
http://intl-outdoor.com/xml-multicell-circuit-board-45a-ouput-55126v-p-543.html

But mine has 3 white rings all the way around that I can see looking into the battery tube.

He didn't copper braid anything that I can see. The springs are different one but they could be thicker and stiffer. He did solder the entire circumference around the springs though.

Ok the new results are in. Check the OP.

Something is odd there for sure. First I would say your meter is reading low. An xml2 tn31 should read a minimum of 140k. And I would expect even a little more than that. I would think a boosted TK75 with XML2’s would be almost there too. Fenix rates it stock at 119.5K and with the boost in amps it should be obviously higher. Just don’t know how boosted it is though.
So basically it looks like your a good 35-45% low on your readings based on the TN31 should be doing. Low, but not sure how low based on the TK75. Now why, I don’t know. But add that same 35-45 percentage to your 195k, it would put you in the appx 260-290k range. Better, but still low for a high amperage IOS driven dedomed shocker. Though if you are really at 3.48A, low for a IOS on PD’s, then upper 200k’s would be closer to normal. Likely still a little low. So maybe you do have some focusing issues?

Your new readings should get you:

TN31 = 148KCD
TK75 = 156 KCD
BTU = 281 KCD.

I don’t have a TN31 or a TK75 but my K40 (dedomed XM-L2 T6 1B, direct-wire) gives me 216 KCD and my BTU (dedomed XM-L2 T6 1Bs on copper MCPCB, stock driver) gives me 225 KCD. :slight_smile:

Compared to other similarly modded K40’s, my K40 is giving much lower lux readings while the BTU I think is just fine.

Wow, that’s quite a spanking the BTU is handing out, expected better from the TK75 to be honest

WOW! Just took the lux readings of my BTU in my office (yes my office) at 11 meters distance (I can only get to 6 meters at home) and I’m getting 3381 lux or 409 KCD at 1 meter. :bigsmile:

I guess the readings I took at home at 6 meters is not accurate since it only gets me 225 KCD!

Too bad my other big lights aren’t with me except for my Maelstrom X10 which gives 349 lux at 11 meters or 42 KCD.

This BTU mod, though still using stock BTU driver, is not bad after all. :bigsmile:

Yeah I think it is a combination of the emitters being out of focus and the driver not going direct drive.



Why would I be getting those numbers though? I took my lux readings times 12^2?


I based it on these figures:

“TN31 XM-L2 (Stock) - 103k
TK75 (XM-L2 w/ amp boost) - 108k
BTU Shocker 3.48a (Dedomed XM-L2 w/ IOS Driver) - 195k”

So for TN31: (1030)(12)(12) = 148,320 or about 148 KCD
for TK75: (1080)(12)(12) = 155,520 or about 156 KCD…

Or am I missing something? :~

If you already calculated throw for your TK75 and got 108kcd, then something is definitely not right.

A 1st gen TK75 gets 90kcd. A 2nd gen TK75 also with that unknown amp boost should give a lot more than 108kcd.

However if those are the raw numbers (eg 1080 lux at 12m) then it seems a little better, because it calculates to 156kcd.

Ooops! :zipper_mouth_face:

I was thinking they were raw lux readings. My bad. :8)

And JOE already edited the OP. Its clearer now. :slight_smile:


Yeah that was my mistake. The numbers were already calculated.