I didn't catch that, but yes. It looks like a thermal throttle at first, but I can't figure out why the output continues dropping past 300 lumens. I'd expect the battery, at 3500mAh, to last longer on high. Maybe not, though.
Do we have to ask gchart for a temperature vs. voltage vs. output runtime graph now? })
Yes, and bypass the springs if possible.
The driver may see a lower voltage drop that way.
On high, it shouldn’t be a problem, but on turbo with active cooling(running), should help.
That’s a bit much (I didn’t measure voltage), but here’s what I’ve got. Realistically, Turbo and High are the same thing except for the first few minutes, you get an extra burst in Turbo.
I haven’t done a disassembly yet, but it sounds like that might be in order. I’m curious as to what kind of driver this is using (linear, buck, or current-limiting resistor). Based on those curves, I’m almost wondering if it’s just a current-limiting resistor. :question:
Thank you very much. Very useful information! I think the Sofirn SP40 really needs a 300Lm mode. The temperature of the flashlight housing at 300Lm is quite comfortable.
But they already have XP-L drivers in a wide array of products . I guess BOM is more relevant, though I question whether this choice could save more than $1 per unit. It seems silly to make this trade-off, but it would help explain why the price is so low.
gchart’s SP40 charts make this light look less desirable, but not worthless. The overall runtime is okay if you don’t mind the constant fall-off.
Here’s one he made for the SP32A v2, which uses the XP-L2:
I’m just wondering if it’s just too heavy to use without the top strap. Since it’s so cheap I ordered just to be able to test out a 18650 headlamp as my others are either 3 AAA or 1 AA.
This one may not have stretchy webbing like the others since it has the strap over the top. I looks more like “belt” material. It may have to have the over the top “belt” to stay up.
It’s pretty stretchy, feels like the same as what’s on my other headlamp straps that don’t go over the head. I think the “around” part would hold it sufficiently as long as you’re not jogging with it.
That’s good to know. I hate jogging so that’s not an issue. I just don’t like something going over my head like that if it’s not necessary. It also makes it take up a lot more space when not in use.
I have plenty of time to think about these things since apparently I won’t get it for 25 days or so. I haven’t ordered from China in a long time so I’d almost forgotten how long shipping times can be.
I too would like to see version 2 come with a lighted switch that is on when the main LED is off. Or, have a 'breathing' feature like the Sofirn SC31. As I'm looking at the pictures, the head seems to be the main physical difference between these two rechargeable models.
Heck, after reviewing your (G's) Review, Sofirn should just copy, but with higher output, the driver in the SC31. Output curve looks more in line with the performance commentators here are asking for.
I've gifted or sold all my SC31s but I'd keep what I'm calling a headlamp version of the SC31. It might be updated it with a high CRI SST20 as the temperature regulation would protect it.
Sofirn, perhaps you could bring this all together in V2. V2 might be cheaper to boot!