I get the same effect with my sample as well. I guess unscrewing the back makes bad contact and the driver detects it as a dropped voltage.
One of mine had a faulty switch and would go into low-voltage mode entirely on its own. When changing modes, it was pretty much random if it would rotate by 0, 1, or 2 modes or go into low-voltage or just give a dim flicker. But I contacted Intl-Outdoor about it and they sent me a free replacement switch. Works great now. 
I had a couple of DIY Hosts that gave me the same behaviour, in the end it was due twice to bad grounding of the pill to the driver, and once bad grounding of the switch.
Need to get the S3.
The emitter and tint choices are a bit confusing.
If I want the S3 with the floodiest beam w neutral tint, which configuration should I choose?
( T5-5C?)
My Convoy S3 just arrived with a faulty tailcap, take 10 clicks to turn on. I have metered it and confirmed the cap is faulty. I would like to get a new cap rather than return this half way around the world for refund/repair. Can you tell me which ones will fit? Cheers
It's likely just the tailcap switch inside the tailcap that needs fixed. Have you removed the retaining ring to get the switch out to see what's wrong (perhaps a bad solder joint)? I can't help you locate a switch, but at least you can stop pursuing an entire tailcap (which you likely won't find).
-Garry
I have disassembled the tail cap and it’s definitely the switch. It is mounted on a 20mm PCB
One of my S3 units had a faulty switch. Intl-Outdoor sent me a new switch for free, since that’s where I got the S3 from, but it took a while.
You might have better luck simply re-melting the solder in your switch, since that can often solve this type of issue. However, I-O and some other stores sell extra switches if you’d prefer to just buy a part.
Just got my Convoy S3 today. It actually gets hot quite quick and feel hotter than my Zebralight SC62w, maybe because of a lack of heatsink?
No, getting hot quickly is a good thing. It means the heat is getting transferred out to the air like you want. If it didn't get hot it would mean the heat is trapped at/near the emitter and could potentially overheat and/or damage the emitter.
-Garry
Your Zebralight has a temperature sensor and dials down the power to keep it under 60Celcius. Your convoy doesn’t have this feature and let’s the heat rise until you decide to turn it down. Your convoy will naturally get hotter than the ZL after a few minutes. .
There is also a caveat to that too…getting hot fast means it’s pumping out ALOT of heat…if there isn’t enough surface area or thermal mass to the light…the heat has nowhere to go fast enough and only heats up the entire unit
This is why lower modes is a good thing…if it’s getting too hot too fast, throttle it back and allow the heat to distribute and convect away…then if you want you can bump up higher for a little bit…this is why I like the STAR firmwares auto throttle function
Do protected 3400 cells (e.g. the ones from Fasttech) fit into the Convoy S2? After reading all posts regarding this, some refer to the S2, others to the S3…
Last I heard, the S3 can take protected cells but the S2 can’t. I don’t know about the newer S2+ though.
Most of the Convoy S line only takes unprotected cells, and usually only cells without any additional wrappers or button tops. It’s fine though, as long as you use firmware with decent low-voltage protection (which all pre-assembled Convoy lights should have).
I used to buy only protected cells, but now I prefer unprotected unless I’m using them in a serial configuration… and I try to avoid serial configs.
It depends on driver’s spring size. Mine with 8,9 mm spring fits at least 68 mm protected cell.
Not in mine, even samsung laptop pulls end up with dents in the top if im not careful.
Personally I would be worried about shorting a protected cell or damaging the cell protection circuit
Hmm, the spring could be shortened…
That doesn’t sound too promising - even after shortening springs.
Are the other S-series Convoy lights any better? S2+, S5, S3, S6?
I would like to get several as “18650 candles” (XM-L 7C with 1050mA).
I have a S2, S2+ and S6 and I’ve never had dent issues with any of my flat top batteries.
Since it’s only one cell and it has a decent driver, it’s probably safe to use unprotected cells. They fit easier into almost everything, and the driver will cut off power before the protection would have kicked in anyway.
My favorite Convoy S-series light is the S7. It’s not good for high-powered lighting since the stainless steel doesn’t shed heat very well, but it looks pretty and is nearly bulletproof. It holds up to wear and tear a lot better than anodized aluminum. Mine runs at a maximum of 1900mA with a Nichia 219B, though I don’t normally push it harder than 900mA.
I have a heap of unprotected Samsung ICR18650-26F 2600mAh, according to previous posts they should fit:
If the driver (complete package from Fasttech) really cuts of completely before 2.75V - even when running at 1050mAh or 500mAh (middle mode), everything is good!
Then these are exactly what I’m searching for - cheap long-running warm white “candles” :bigsmile: