Convoy S2+ red 6*7135 faulty? Lightness/Time Diagramm

[Orodreth]

Hi everyone,

i just bought a red convoy S2+ T6 4C 6*7135 for my MTB. I read that 6*7135 can sustain its high mode permanent without getting too hot. The T6-4C is a nice tint. Got it from Fasttech. Drive, package, etc looks absolute genuine.

I put some fully charged batteries in it, but i was surprised that it lost its brightness very rapidly. As a constant current flashlight i thought it will keep its brightness till the voltage drop unter an certain limit.

I measured at the tailcaps on high only 1,75A with fully charged batteries. With this Driver ist should be 2.1A. On mid it was 0.75A. Voltage was 4.11V

So i made a simple test setup with my smartphone as a luxmeter. The absolute values are here not that important but the relative values.

I measured it realtime and put the datas it an excel sheet. (see attachment)

Question: Is my flashlight broken or is that a normal behaviour? It looks strange that it is not much brighter than on Mid.

After 60min, i measured on high 0.90A on Mid 0,71A.

Then i used another battery from Samsung to eliminate the possibility of a faulty battery as the cause of this behaviour.

I also measured only 1.7A on high with a fully charged battery.


Before i will contact the seller, i want to know what kind of behaviour of your S2+ flashlight has. How much ampere do you measure?

Thank you in advance


Diagramm Lux/time

 

[Zak]

I tested an S3. This has an 8x7135 driver and a Nichia 219B emitter, both of which increase heat relative to yours and should result in more thermal sag. Here's a graph of the first minute on high (battery: Sony VTC6). Note that 100% is the value at 30 seconds, as is used by the FL1 standard:

 

[WalkIntoTheLight]

I have a couple of Convoys with the 8x7135 config. I don't find them very good at holding a constant output. The lights lose about 25% of their output when the battery is half-drained (about 3.7v - 3.75v) compared to full (4.2v). This is with a high drain 30Q cell, so there shouldn't be too much voltage sag.

It's better than a FET driver, but I expected better from 7135's. I guess 8 of them is too many to hold a constant current.

Go with a light that uses a boost driver if you want reliable constant output.