In-depth review of ThruNite's latest powerhouse, the TN36 UT featuring a trio of Cree's XHP70 emitters from their SC5 Technology line. 7300 lumens... 'nuff said (for now). Please stay tuned for Part 2 which will cover a bunch of measurements and runtime charts.
Just wrapped up the runtime testing and below are the results (the current measurements will come later).
RUNTIME & OUTPUT
The relevant battery stats are provided above each runtime graph along with:
- voltage of the battery at the start and end of the test
- current draw (to come)
- actual runtime using ANSI FL1 (first in HR and then in M; so for the TN36UT read it as 1.4hrs or 83min)
- lumens measured on my PVC LMD @ 30 seconds (calibrated with TN36 on medium mode w/Extech HD450 in 40K range) as well as the average lumens of the entire run
- the temperature: ambient, the head/fins at start and the max it reached (USB fan was used on lowest setting for all runs)
Mini TN30
- particular sample is a potential overperformer (I will redo lumens measurements, once I get my custom glass for my PVC LMD but for now, the consistency is within ThruNite's lights here) and I measured 3520lms @ 30 sec (recall that ANSI FL1 requires an average of three lights and for those who would make an argument that LED light variance should be negligible... as a FYI I've measured two of Nitecore's TM26 w/>10% difference in output)
- is capable of reasonable sustained output on Turbo, or as much as is possible for a light of this output and emitter (XM-L2)
- gets as hot as the TN36 UT with max temps hitting 157F (measured at head); at this temp 2nd degree burns are possible with contact of the bare metal for 1 second or so and 3rd degree burns for 2 seconds; USE OF CONTINUOUS TURBO MODE SHOULD BE EXECUTED WITH DUE CAUTION!
- runtime achieved was 16 minutes shy of mfg specs but caveat is that the cells only charged to 4.19v/ea ahead of this run (however, it's unknown what cells mfg used)
TN36
- particular sample has extremely aggressive ITC, output nose-dives immediately after turn on (max captured at turn on was actually 7.1K lms) thus output measured at 30 seconds was only 5830lms
- will then enter a decently regulated mode for the rest of the run averaging 2390lms
- the temp probe must have been a little off for this run as I actually measured the barrel at around 115F (46C) approximately 2hrs in
- runtime far exceeded published specs (3hrs vs 2) since it never sustained Turbo mode meaningfully
- will tear head apart to exam what might be causing this
TN36 UT
- as with the Mini TN30, this particular sample is also an potential outperformer with 7850lms measured at 30 seconds
- output curve is actually similar as well (but of course with a much steeper decline given the difference in capability) thus leading me to believe it does try to sustain Turbo mode
- this does come at a cost of extreme heat with max temp reached of 160F (again, please use caution running Turbo mode continuously)
- runtime achieved was 12 minutes under published specs (again, it's unknown what cells mfg used)
Common to all three lights
- will just suddenly cut out immediately once the batteries are depleted (avg. resting voltage measured ~3 min or so after testing were ~2.9V for each cell), however the Red low battery warning LED should give you ample warning in advance of this
- all feature excellent current control circuits (just shame TN36 was hampered by aggressive ITC)
- current draw for electronic switch is so low as to be no concern (~14.6µA); to put that into perspective (and leaving the self-discharge out of the pic), calculated stand-by time would be ~27yrs on 3400mAh cells!
PART 2

Specs in Blue section is as per Mfg; figures in parentheses are my corrections of calculation errors by mfg (i.e.: 42kcd calculates to 410m beam distance and not 440m) | section in Red are my measurements on Extech HD450 (non-NIST)