Thrunite TC20 - XHP70 - 3800lm

Yes… it make 3800 lumen with their way of measurement… we dont know how they take the measurement… turn on lumen ?

Either way, i am not concerned… i am here to play with the TA tube and have fun…

Robo tested his at 1792 lumens in high, 3806 in Turbo, he found it maintained output pretty well up into 80 or 90 seconds, if I recall correctly.

Robo has a review on it with run time charts, for what that’s worth. Tested various cells in it as well.

I was looking hard at this one earlier today, decided on spending the money for components and driver boards instead, reckon I’ll build my own as there’s more challenge there. lol

I did get 1750 lumen on my thrunite catapult v6 ( 1700 lumen )…

My TC20 (NW) gets 2960lm on Turbo @ 30 seconds on the TA tube, using the .7 correction factor
I’m using the included Thrunite cell (fully charged) and have meticulously cleaned all contacts.

Using the same correction factor, all of the other lights I’ve tested besides this one pretty much live up to their factory specs, including some ANSI rated lights.

TBH I’ve been wondering why I’m not getting anywhere close to the advertised spec of 3800lm.
My thought was the 3800lm rating is LED lumens, Thrunite’s website does not show anything about ANSI ratings that I could find.

Figures for some popular (non ANSI) lights on the same tube using the same correction factor:

BLF Q8 (stock)…………4865lm
Sofirn C8F (stock)……2338lm
(Both tested @ 30 seconds with fully charged 30Q cells) These readings appear to be pretty much in line with the factory ratings.

At first when testing the TC20 I wondered if the tube was reading low, however the 4 ANSI rated lights I tested (Eagletac, Jetbeam, Nitecore) were nearly spot on to the factory ANSI specs.(within 4lm to 50lm)

My TC20 NW does 3530lm after 30s with a liitokala 26650 cell. Other lights give similar results according to their specs so I’d say accuracy is OK

You may have mentioned it before, but I’ve forgotten. What are you measuring with? A TA Tube, JoshK sphere or a sphere like DB, Tom E and Robo use?

it’s a tube like the TA’s one but made by myself a year ago.

I’ve tested a lot of flashlights in it and all give accurate results

Accurate to what? To certain other forum members results, to ANSI-FL1 rated lights or to Maukka’s Lisun integrating sphere setup?

Pics of his setup.

I don’t mean to turn this thread into a discussion about integrating sphere calibration sources, but I’m trying to show why I think TA’s lumen tubes are going to be more accurate (not perfectly accurate) than certain other tubes or spheres. For many years people have been calibrating loosely to rated specs and each other instead of to proper certified sources - generally speaking. There are some guys on TLF that have some pretty impressive setups.

TA’s tubes are still not the definitive source since the production versions are all calibrated plus or minus 5% to his original tube, but we all can’t have $10k sphere setups in our house, either.

If I started an integrating sphere/lunen tube thread, would you guys be willing to show some pictures of your setup?

I’ve got a JoshK and Texas_Ace setup so I need pics of other devices.

BTW, the JoshK sphere tends to read roughly 3% to 4% lower than TA’s Tube.

Mine , Dales , TomE and Richards are all made from 4 inch schedule 80 PVC , painted black on the outside and painted with pure white on the inside. The opening where light sits has dark grey foam cutouts of different sizes to fit different light tubes.
My meter I use with mine (the meter it was calibrated with) is a Mastech LX1330B.

BTW, on this particular light I was comparing Newlumen and Robo819’s results. I wish they could test on the same battery.

On High:
Robo819 1710
Newlumen 1550
Difference of 160. That’s 9.4% lower than 1710 and 10.3% higher than 1550.

I’m not sure what turbo readings to compare. Maybe:

Robo819 3560
Newlumen 3090
Difference of 470. That’s 13% lower than 3560 and 15% higher than 3090.

So maybe Robo819’s sphere is only 10% to 15% higher than the TA Tube, not 20% to 30% like I said earlier.

Are there any diffusers in the tube or is it a straight shot from end to end?

No diffuser in it. Dale would probably know more than me about how the calibration was all done though , because he is friends with the one who made the tubes.
Don’t know if you been here long enough to remember “manxbuggy1” or not but he made the tubes.

Edit: one thing I didn’t point out is that these tubes are made with a 1 piece P-trap and not made with several 90’s pieced together also. I don’t know if that plays a factor or not but thought I would mention it.

I think i might have did something wrong in my previous test… i am not sure… i will make sure the light is align with the disc… i will report back this afternoon…

I welcome this discussion here as it pertains to the TC20.

I’m not doubting the validity/accuracy of DB, Tom E and Robo’s tubes or anyone else’s, I’d just like to know why my TC20 doesn’t appear to have near the rated output.

I remember reading years ago about manxbuggy1 making those tubes and I’ve always trusted the readings posted by DB, Tom E and Robo.

Since I’m getting what appears to be proper figures for all the other lights I’ve tested, I’m thinking my TC20 may have something wrong with it. As soon as I get some time I’m going to test it further with a Lii-50A and also test the lower modes.

.

I am curious if Dale or Robo got similar figures to mine for these two lights? (If they have them):

(My readings):

BLF Q8 (stock)…………4865lm
Sofirn C8F (stock)……2338lm

(Both tested @ 30 seconds with fully charged 30Q cells

This is what I remember, the foam cutouts and the light sits on a piece of glass? (I vaguely remember reading it may have been a special type of glass?)

I like this setup, it seems it would be a bit easier to use and every light tested sets at the same place.

.
With the TA tube we have to hold the lights in through a open hole and move it up and down to get the “best” reading (no glass to set the light on)

There’s no foam so some light escapes around the opening if the head of the light isn’t exactly the same diameter as the hole.

I’m not complaining, it’s not really a big deal, but the glass/foam version would seem easier to use, especially for testing longer runtimes, 5-10 + minutes, or even 30-60 minutes, can’t really hold the light for that long.

I did the turbo mode test last night and got 3192 lumen…

I tested it again this morning with fully charge battery and make sure the light is align with the disc… I got 3220 lumen…

So my last two turbo mode test are 3192 and 3220 lumen.

I think it’s pretty clear that the TC20 specs are overrated. The driver is just not producing the power to get 3800 lumen at 30 secs.

The NW emitter might be a bit lower in output with this type driver. I think Robo819’s tc20 was CW. Does Thrunite mention what emitters they use? They might be using a NW that is 1 or 2 bins lower in output over the CW. Who knows?

The factory protected battery might also be playing a role.

2960 lumen is pretty darn close to 3087. It’s only 4% less. TA’s tubes are only rated at plus or minus 5% so if Newlumen’s is reading 2% high and yours is reading 2% low, then that could also explain it.

I would not worry too much. We will never get exact numbers.

Do see if a better battery helps.

Geez, now you mess up my numbers. Lol.

Okay, so now Beamos light is measuring about 8% lower than Newlumen.

What is Crees 70.2 deviation per bin, plus or minus 7%. We are still in that neighborhood.

A good battery might get Beamos numbers higher. Even a good old 30Q will probably get higher output than the protected 26650. At least a lower amp draw, that is for sure.

Yes mine has the CW emitter in it………and if you have been arguing that my test are wrong at 30 seconds then that is correct……

I got 3791 AT START and 3560 at the 30 second mark , as noted in my charts I put in this thread and in my review.

Yes we have the foam that covers the opening where the light sits and various size holes in those pieces so that the head of the light sits down on the glass and the foam puts each and every light to the same spot in the center and I don’t touch anything when taking the reading , other than pushing the switch to get the next mode.

I don’t have the Q8 , but my 30 second reading on the Sofirn C8F was 2551 with the Sofirn cell.
I actually got higher readings with the Sofirn cell than the Efest purple high drain 3000mah and slightly lower than the LG HG2.