XM-L 3-18 volt Dropin Shutting Off

It's been in the family since December 16th now. I've had that much time to play with it. This is the Kaidomain version of the XM-L dropin, 1 mode, 3 to 18 volts. I got it for the purpose of upgrading my older P60s. But through a friend's surprise gift a week later, it had a body all it's own--a Solarforce L2X (also known as the meat tenderizer body!

I have tried this light at 4.2 volts to 16.8 volts and it works beautifully. When driven harder, it gets brighter. In fact, this XM-L outdoes my manfont Ultrafire C8 by a bit. I wish I had more modes, but the output is direct, yet floody, and yet powerful enough to project quite a ways. Gets warm rather quickly, too.

Got some new Tenergy rechargables for it. Seemed to work fine for a day, but then tonight, shut off on me after less than 5 minutes of use. I clicked it back on and no apparent problems. Any ideas why that happened?

Well as far as I can tell is possibly one of three things:

1. The protection circuit on the Tenergy cells did something funky.

2. There is a bad connection somewhere (most likely the tail-cap) however this does not seem very likely from the description you gave.

3. The driver board did something funky (does the driver have any protection features built in that you know of?).

If this has never happened before with any other cells my guess is that it is the protection board for the cell. If the problem repeats itself you could try to isolate the problem (e.g short out the tail-cap.. if it continues to happen you can be sure it is not the tail-cap).

It does it repeatedly, and if clicked back on and on again, will shut off faster. I've tried perhaps a dozen times and always with the same result. No flickering, no signs of anything else. Just shuts off after the same initial amount of time and then sooner if I try to continue.

So what would be causing the protection board to act this way and what can I do about it? I have heard people say RCR123s act funny in high-performance lights. Maybe this is what they mean.

Have you tried different batteries?

A set of RCR/16340s did the very same in one of my applications- after I had accidentally dropped one of the cells down a staircase, damaging the protection circuit.

Well, as it turns out, I got home and tested the other two cells in the four-pack...and they don't auto-shut off even after an 8-minute constant on. Looks like one of the other cells is damaged then.

It's not very reassuring to think that any dent or bang in my pocket could damage the cells. Maybe that caused this. I'm toting this thing around work.

Because they are far more delicate than, say, eneloops, I carry spare my 18700 Li-Ion in a padded pouch from lighthound ($2.99 was budget enough for me). For 16340s, I'd use those nifty "battery caddies" (they come in a variety of colours, even the brightest and longest lasting GITD I've seen, btw). There are battery cases which come even cheaper, in the 1-2 dollars range.

Cell protection and careful handling is always a good idea, especially with RCR Li-Ions.

I have had my share of wasting good cells last year; one I killed by deep-discharging first and then letting sit for months like that (lacking a proper charger back then, d'uh!), another one rolled off my table and hit the floor tiles. Now I know that you "just don't do" things like that.