NightWatch Avaritia NA40

if I followed correctly you did report that to Neal too and he already sent you the replacement?

You helped me forwarded my request to Neal at first. I haven’t reported it to Neal directly.

Btw, which 26650 did you use with this?

Got my original NA40 updated with a piggyback'ed 17mm DEL driver running NarsilM - really nice now. Didn't take apart the switch but tied the red and green wires to the LED pin #3 and seems like I only got one working LED in there - seems to be RED but looks orange. In room light it appears only on one side of the switch but in the dark it's a definite orange and looks consistent throughout the switch - I like it .

It's a nice quality light all around - love the anodizing, SS bezel, square threads and separate charging circuit. At best I got about 17.5 amps out of it, 5950 @start, 4980 @30 secs (my lumens). Losing about 1000 lumens in 30 secs is excessive for sure. Not sure what's going on there - thinking the MCPCB mounting is not ideal. Maybe it's not tightly pressed down by the reflector, not sure.

The biggest issue I have is the weird battery tail (negative contact) setup. It's the oddest setup I've ever seen. It seems like a spring is just simply missing? stock LK's rattle and can't make contact. Typical magnets on the tail are too small in diameter -- totally weird stuff. Why??? Hope they fixed this up in the SE upgrade? I use solder blob top LK's with a magnet off centered on the tail - not ideal but no rattle and it basically works.

I stripped the stock driver to use as a contact board, epoxied the 17mm on top. Looks like the MCU is a ATTiny84, 14 pin surface mount, and some of the cap and resistor design closely matches the DEL driver designs. The 16 7135's are divided into banks, at least 3, maybe 4-5, not sure. Because the 84 has a ton of I/O pins, it makes it easy to do and you can optimize your mode sets to be full sets of 7135's at max output - no PWM's. I almost considered air-wiring in a ATTiny85 to use the existing 7135's and FET's, but would be a challenge for me.

Wish I knew the details of exactly what they changed in the SE model - for example "improved switch", well, what was improved? Could it be it stood out too far and was too stiff? Why was the reflector swapped and what's the advantages? I could speculate maybe it frees up space for the wiring - they had to epoxy up the exposed wires, so maybe there's some true interference going on there, maybe resulting in a poor MCPCB bonding to the shelf. Shame because it's a really nice light, great for modding. It's like a 26650 version of the C8F, but nice charging setup, better quality body, though the C8F isn't bad at all. The driver size of 32 mm is non-standard for us, sorry to say -- no one on BLF makes a 32 mm, or one that can be tailored to 32 mm as far as I know, but the piggyback works well.

Even with the issues, they are relatively minor. The original NA40 is a nice light for the money - I don't regret buying this one. The NA40SE hopefully improves on or eliminates these shortcomings.

I just tested all my 26650 batteries, all of them works fine with my original NA40.

Where did you buy this NarsilM driver?

Appearantly DEL built it for him. He made it himself based on Del’s design.

If you want to buy one ready to go you can see Lexels thread on them.

I just got the replacement tube from Neal. :+1: I think it was the springs. The springs on this thing can get crushed easily. Otherwise I really like this light. It has good mass for heat sinking. I measured 3,970 lumens at 1s using freshly charged shockli 26650 5500mah on my TA lumen tube with Maukka calibration.

I think the light output is being severely limited by the springs. They are probably phosphor bronze/BeCu short springs can carry quite a bit of current, especially if it’s really stiff, meaning it has very low contact resistance initially.

The problem however is that it takes into account if the light is new. Pure copper oxidizes very quickly, meaning contact resistance shoots up dramatically, and even faster with heat, which can great hot spots, and contact resistance goes up because of heat.

Using gold plated springs, or even better, dual springs, would help a ton in this regard.

You are probably right. The original springs that came with the NA40SE is very thick. The replacement is thinner with more loops, which I’m guessing is from the version 1 NA40.

Seems quite bright for 3 emitters. :+1:

My xhp70.2 (4 emitters) and FET driver with 2 x 26350 got 4100lm measured similarly. I bet using that single Shockli is way better than my 26350 cells.

This NA40 would be pretty sweet with a better UI like Tom E used. You retain the charging as well. That’s one advantage compared to building up a C8F 21700.

Did you happen to measure how many amps it’s pulling across the tail cap on turbo?

I don’t have the equipment to measure amps.

I’m waiting for my Nightwatch heavyweight XHP70 light to come from Enogear and see if the NA40 tube fits. That would add USB charging to that light.

If you ever want to:

For tail cap amp draws, all you need is a $30 UNI-T UT210E clamp meter. That's the model a lot of BLF folks use due to the big Group Buy back in 2016.

The process looks like this.

The UT210E can also measure voltage.

my NA40 pulls nearly 15A with fresh 26650 cell, so my wild guess is about 5000lumen
the light is also equipped with temprature control, because the turbo last much longer when using this light under water

For anyone who is waiting for this light, available stock is coming back on Taobao on 10th Oct 2000h, beijing time.

Anyway, more details and more pics can be found in the Taobao item’s review section, which number 410 reviews.

Yes, that’s probably the reason why folks aren’t getting much comfortably above 4000 lumens, much less hitting 6000 lumens.

A single cell gunning 6000 lumens at very high amps is going to place a lot of stress and emphasis not only on the 1 x 26650, but also on the springs, the cleanliness of contact points, all the components in the power path.

You cannot use the Keeperpower 26650s, they are like mid current cells only.

The best Keeperpower 26650 vs Liitokala INR26650 @ 20A “only”. I think we need to look at 30A (see subsequent posts).

And this is the VTC5A vs Liitokala INR 26650 @ 30A. Sony VTC5A wins

To get the absolute best measurements at start-up or within 1-20 seconds, i guess you’d need the true heavy hitters.

Bring out the Samsung 20S INR (Vapcell 2000mAh black)

Samsung 20S vs Sony VTC5A @ 30A. No contest.

Yep. To get this power out of a single cell, it is imperative to reduce resistance as much as possible.

The biggest one here is the spring. Why aren’t they using dual BeCu springs, or at least, a coated spring? Uncoated copper alloy springs will develop oxides on the layers overtime, boosting contact resistance, and creating hot spots, and boosting the voltage loss even further.

That means even if they are using the highest conductivity BeCu C17500, performance will get worse over time.

Look at djozz’s test on the SST-40. In the best scenarios, cooling and excellent bins, it needs 6A per emitter at 2000 lumens. If you want 6000 lumens OTF as measured in all of our ceiling bounces/lumens tubes/integrating sphere, you’d need much more after factoring all the lens losses, driver losses, heat etc.

Probably need 2400 lumens in dijozz’s test if there is a 17% loss to 2000 lumens OTF, thus 9A per emitter.

I am guessing 27-30A at the tailcap is gonna be needed, a fair bit of which is really heat and not lumens. Don’t even dream about efficiency once comfortably past 6 amps per emitter.

Definitely 12awg copper bypass for this jobbie, just strip the insulation and do it. :smiley: Enjoy the smoke if the light does puff though.