[Review] Convoy C8+ || OSRAM KW CSLNM1.TG , 1x18650 || Output, Power Regulation Graph, Beamshots

The flashlight was sent to me by Convoy for review.
Here's the product's link: Convoy C8+ w/ KW CSLNM1.TG & Lighted Switch


The Convoy C8+ comes in a variety of colors (desert tan / black / silver / orange / green).
The overall fit and finish is excellent.



Its body contains some knurling for added grip.
The head and tail incorporate an anti-roll design, which prevents the flashlight from rolling over.



The head of the C8+ comes with some thick heat-sinking fins for better heat dissipation.



The front glass lens of the flashlight is protected via a metal bezel which is slightly crenulated.



This specific variant of the C8+ comes with an OSRAM KW CSLNM1.TG emitter and a smooth reflector.
The emitter is perfectly centered thanks to the centering ring.



As with all Convoy flashlights, the C8+ can be easily taken apart.
Removing the front bezel gives us access in the reflector and emitter MCPCB.



Here's the OSRAM KW CSLNM1.TG emitter and its copper board.
Plenty of thermal paste is in place.



The driver is seated in the rear part of the head and is secured in place via a brass retainer.



The tail of the flashlight houses its mechanical switch.
I decided to install a red illuminated switch, as such color complements the black body of the flashlight nicely.



The illuminated switch kit also includes a translucent tailcap to allow the light to shine through.



The tail uses a thick copper spring and the PCB is held in place with another retainer ring.



Here's the tail assemble taken apart.
As said, I've installed a red illuminated tail switch.



Here's the illuminated switch board (left) compared to the standard board (right).
As expected, the illuminated switch contains a couple of resistors and emitters mounted in the sides of the main switch.



The rear threads are square cut and anodized, which allows the flashlight to be mechanically locked out.



The head's threads are also square cut, but come with no anodization.



User Interface

There are two different firmwares that the C8+ w/ KW CSLNM1.TG can be ordered with:
1. Simple 4-mode : 0.1%-3%-30%-100%
2. Biscotti (12 mode-groups)

I chose my light to use the 12 mode-group driver, as it allows for better flexibility.

Here's a diagram demonstrating all the features of the 12 mode-group driver.
Please note that since posting this diagram, Convoy has increased the numbers required to access the config mode to 20 taps (was 10 taps originally).



The 12 mode-group driver includes Low-Voltage Warning and Low-Voltage Protection.
Additionally, as can be see in the previous diagram, mode memory can be toggled on and off through the configuration menu.

Output
Here's my output measurements along with the respective current draw.
The measurements where recorded using a Samsung 25R cell.



The Convoy C8+ w/ KW CSLNM1.TG pushes more than 1000 lumen at startup.
Such output is very impressive, considering that the emitter is 1mm^2.

Power Regulation
Here's a power regulation graph I created for the Convoy C8+.



What we can see in the graph:

  • Turbo (100%) is linearly affected by the input Voltage.
  • Medium (35%) is fully regulated down to 3.3 Volts.
  • Low(10%) and Moonlight (1%) are fully regulated for the full span of the battery's life.

Outdoor Beamshots

Here's a few outdoor beamshots that I captured with the Convoy C8+ w/ KW CSLNM1.TG




Great review. Surprised to see that the driver doesn’t regulate much better than this. Vf of nm1 emitter at 1.9A is only 3.2V and 4.3A comes at about 3.6V. I’d expect to see regulation go much deeper than this.

Is there any coupon code?

and btw, I don’t see any photos

Thanks. I wonder whether the illuminated switch could have higher resistance than the original switch.

Original switch in that model is bypassed from the factory so it should have less resistance.

I have one of these, only in desert tan w/ no lighted switch and the 4-mode driver. DAMN does it throw far.

I should also point out that the host warms up pretty quickly on sustained higher modes, so the assembly is definitely wicking the heat away from the emitter nicely.


I think Simon from Convoy provides a coupon code for all BLF members.
I'll double check with him and keep you updated.

Regarding the photos, I've hosted them in imgur.com
In the past I remember hearing from a folk living behind the Great Firewall of China having similar issues.
Could this be the case with you too?

The throw of this light is indeed amazing :slight_smile: Now I am waiting for the 18350 tube to arrive. The long throw / short body size combo is definitely going to be very interesting!

You’re correct. I was also expecting a bit deeper regulation in the 35% mode judging by the low Vf of the emitter. (Please view post #10 - Had some technical difficulties with my PSU’s leads :smiley: )

Were you measuring the voltage right at the driver? Maybe you didn’t account for voltage losses between the power supply and the driver?



You're absolutely correct. Thank you very much for the suggestion!

Backtstory
I use pretty thick leads for my power supply leads, so voltage drop isn't as issue at such current draws.
I took your advice and decided to also get the voltage readings right at the driver, where I observed a 0.22v voltage drop @1.91A...
This is when I noticed that the half of my PSU's positive lead strands where ripped off from my U-shaped terminal connector

Patched up a new terminal lead, and here's the corrected power graph.

As you can see, the regulation for the 35% mode is down to 3.3V
Also, the max current I recorded also got bumped to 4.76A, which is completely aligned with the ratings reported by Convoy!

I ordered the green one, my first green light.

Btw, now I can view your op photos, for what reason, I don’t know.

The new lighted switch should also be bypassed in this flashlight. Not too hard to do, but should be done since the current is over 3 amps.

Nice review bilakos10!

The green one looks fancy :sunglasses:
Did you get one with the OSRAM CSLNM1.TG emitter?

I think there is still something fishy with the measurement. From djozz’s test the voltage of the NM1 is ~3.35V at 4.76A. So that means there is a 0.85V drop somewhere. In my experience the voltage drop across a linear driver like this is a lot less than that, something like 0.2V. If you measure the voltage at the actual driver input that should be more accurate.

Your measurement is suggesting that there is zero regulation time in high mode, and I think that is incorrect.

I have just received a Convoy C8+ with the CSLNM1 as well and love it! I also have a S2+ with the CSLNM1 and I run them both on 50% power to protect the LED. The C8+ is a giant step up in throw from the S2+ - the useable distance (where I consider something very well lit) for the S2+ for me is around 50m (165 ft) and pushing out to 75m maximum (~250 ft) before the light has fallen off too much, but with the C8+ I found an object at 150m (492 ft) to be very well lit and even very well lit out to 200m (656 ft), but by that distance my ability to see fine detail is now becoming the weak link! The hotspot is only half the size of the S2‘s, but at 150m the hotspot of the C8 should still light up the whole side of a car so it’s not crazy narrow. I think the C8+ with the CSLNM1 might be a bit of a “special use” flashlight though as it really only shows its usefulness working at longer distances, so for shorter distances (upto 50m / 164 ft) I would probably choose my S2+ over the C8+. I’m glad I have both though!

I found the C8+ super useful for looking into murky narrow openings while the outside is bright (e.g. a pipe in broad daylight), but the S2+ should indeed be more convenient for that owing to its form factor.

A zoomy light might give the best of both worlds if you have a need for a focused beam, but also want good flood at other times.

Maybe, but I prefer dedicated lights. The only zoomie I intend to buy is the Convoy Z1, which is not on top of my purchase list.