ArmyTek Viking Pro V3 Run Time Graph - (Full Regulation?)

I wanted to put up this run time graph I did of the Viking Pro V3 on max mode (head tightened) to see what you guys think.

ArmyTek states that the difference between their Pro version and the regular version (in addition to the extra firefly mode on the Pro), is that the Pro version has "full regulation" in maximum mode.

So I did this test. What I found is that after about 4 minutes it steps down to about 57% of max output. It flashes a couple of times when it does this. It stays there for a little bit and then it goes back up. It repeats throughout the entire discharge of the battery, flashing a couple of times for each step down. Now I'm using a freshly charged Panasonic NCR18650B battery with very few cycles on it, so I doubt it has anything to do with the battery.

I have tested a couple of 18650 lights and they step down before they get real hot. So my first impression with this Viking is that it might be necessary to step down to prevent damage........and I was questioning how they could actually have "full regulation" on the light. But if that is the way its suppose to be I want to make sure mine is functioning as its suppose to.

I wonder just exactly what "full regulation" is? This wasn't exactly what I thought I'd see. If the light has a flaw, I question why the output is so predictable and organized............its like its being thermally regulated after it warms up. My thought is that a failure would be more catastrophic. I will say it gets very hot to the touch.

The light performs flawlessly in the "head loosened" Main3 mode...........very well regulated right up to when the battery is completed and goes a little over 3.5 hours just as the specification says.

For max mode, I'm going over 1.5 hours whereas the spec says 1.1. I can see why I'm going longer if the average output is less. Something doesn't seem right either with the performance or with their specification.

I would love to hear from others with this light. Run your light for about 10 minutes on high with freshly charged battery and tell me what you see and how hot it gets.

I think in the Armytek vendor section this came up and it was determined to be a defect.

Woods Walker said:

I think in the Armytek vendor section this came up and it was determined to be a defect.

Click to expand...

Ya, I'm still waiting to hear back from ArmyTek customer support. The U.S. dealer just got back to me so we'll see what they say. Still I question how organized the defect behaves and how they can actually run a light that hot for over an hour. I almost prefer it to behave this way. But I'd really like to know. When I saw someone else with the same problem my first thought was that this is how its designed..........but that is just my initial thoughts. Now I'd like to see others run this for at least 10 minutes to see what theirs do.

Let us know what yea find out. Personally my experience with the brand has been less than stellar so going to stay away for now.

Can you try running it with a fan? Sounds like thermal throttling is kicking in, which explains the trend of slight output sag and the extended runtime (throttling reduces current).

StudFreeman said:

Can you try running it with a fan? Sounds like thermal throttling is kicking in, which explains the trend of slight output sag and the extended runtime (throttling reduces current).

Click to expand...

I was in the middle of another test using a different battery when I read your post. I suspected it was being thermally regulated but didn't think to put a fan on it to prove it. So I did and noticed that it would stay up for longer periods. I'll have to wait until it finishes and then post the chart.

On another note, my dealer said that the light is working normally as it does it on the one he tested too. ArmyTek person in the CPF vendor section suggested that I had a failure, but I wasn't sure because what I saw was organized failure.........something that you normally wouldn't expect for a failure.

I've also run a test on an EagleTac S200C2 which is a similar light. I'll post these comparisons.

After following StudFreeman's advice on the fan, you can see where I placed the fan on the Viking........somewhere around the 25 minute mark. That proves that the AT Viking Pro V3 is using some type of thermal feedback to the driver. Not sure why they used the term "full stabalizaion".........as the behaviour isn't maintaining "full" regulation at all with step downs. But it is what it is. I noticed that the Viking seemed the hottest to me. Maybe that's because there is more mass on the SRT6 and the S200C2. The Fenix PD35 steps down at the 5 minute mark and 30 minutes later steps down even lower. The PD35 has straight line regulation but perhaps the necessity to step down earlier than these other 3 is because of even less mass in the light for heatsink.

So here we have 3 lights that I've tested on max mode, the Viking, the Nitecore SRT6, the ET S200C2. I've learned you cannot hold a solid regulation at these drive levels due to the heat I presume. Therefore, I will continue to only use the max mode as I have in the past simply as a momentary blast of light for spotting and show- off .

Edit: of note is that this test was done using a freshly charged KeepPower 3400mAh battery on all three lights.

Cool, thanks for checking that. I suspect the light would do alright if held in hand. In use, your circulatory system will probably transfer heat away from the light fast enough to prevent stepdown. I think they can claim "full" regulation because if it's cool enough it will keep the LED fed with constant current as supply voltage decreases.

Looks like adding convection cooling (the fan) permitted the Viking's output to step back up and remain at ~95% of initial brightness on a semi-depleted cell (Buck-Boost driver behavior). Appears the Eagletac demonstrated behavior of its Buck-only circuitry.

Cool tests, thanks for doing them!