Review: Four-way Convoy S2/S3 mini-review

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:

You just need some custom firmware in the driver to make the light flicker like a candle. Hmm, my wife would love something like this.

There are already “lifelike” flickering LED candles to buy, even from Philips, but they use proprietary rechargeable cells with low capacity, because of the form factor :party:
They are however very low power, like real candles, so they are more a gimmick than usable lighting. I’ll use the Convoys outdoors, and will put a diffuser over them. One working option is the good old white balloon - nice weight-to-size ratio, and customizable size! :bigsmile:

My s4 won't hold a protected cell. It's too long, and puts too much pressure on the driver.

I noticed a my new gray S2 host has a distinctly blueish tint to it. This is the first time I’ve seen that much tint in a natural gray hard anodizing. Anyone else get one like that?

We have one of the flickering candles your speaking of. I find them fairly useless. If I could get that functionality and have a decent flashlight it would have more Waf (wife acceptance factor).

I like the idea of using a balloon for a diffuser!

I’ve been tempted to do that. I made something to simulate lightning, but haven’t done a candle flame yet. I usually just tail-stand a light on “low” (or even “moon”) when I want something candle-like.

It’s hard to include randomized behavior modes in regular EDC firmwares though, since a good random number generator takes a lot of space. But if we ever start using the attiny25 instead of attiny13, there should be plenty of room to include a candle mode along with regular flashlight functions.

Then again, I just freed up about 260 bytes on my clicky EDC firmware… maybe I should use that room for a candle mode. :slight_smile:

We have some that came with a wireless remote to turn them on. It’s obvious they are fake candles because they flicker in sync so it can’t be random. Turning them on one at a time is the only way to make them flicker out of sync. Unfortunately, it’s not easy to do that with the remote.

My S3 from Fastech can take Panasonic 3400 protected but not the S2, the cell was to long.

Here's a thread about candle flicker.

After some hours of thinking, simulating and programming, I could reproduce the statistical behaviour described in the links there in 140 bytes (uhm, sorry for showing-off, but I am a bit proud about that). I also integrated it into my RGBW firmware, adding some red&green for a warmer tint. Quite nice, used it a few times. Brighter than a real candle though (a real candle has about 12 lm).

However these candle flicker modes are unrealistic in one respect: Inside a room (no draft) most candles I had just burned very steady most of the time, i.e. no flicker at all.

Can someone here measure there S3 and S2 brass pills, curious to know the depth of each one. The S2+ has the deepest but no one in the US has any in stock

I just got my S2 today from FT.

I was testing it out and one of my tests was lengthwise smacking of it’s tailcap end against my palm.

I swear, at some point it started flashing in low mode at perhaps 1-2Hz (once or twice per second). This was a flash controlled by the driver, not an accident due to loose contact. Now I can’t reproduce it anymore. I’m not certain if I hit the switch at all or was it contact break due to battery shortly breaking contact, though I suspect it’s the former. My protected battery is pretty firm between the springs.

This one is advertised as 3/5 modes model, but it obviously has some secret mode(s).

Anyone have any info on how to access it again?

I like beacon modes, though I prefer to keep them hidden by default if possible.

Thanks,
Viktor

Edit:

I can reproduce it, but only by hitting it against my palm instead of by operating the switch. My palm hurts a bit. :slight_smile:

Is this low voltage warning that’s triggered by momentary loss of contact?

I’d estimate it’s a 1Hz high duty cycle flash. Roughly 900ms on, 100ms off, rinse, repeat.

Yeah, that’s low V protection kicking in. Tested it out and confirmed by draining the cell.