1) First few days resulted in a damaged regulator with the SSC P7 because the darn thing didn't have a warning on it that it can't be operated above 4.2V
Link the product page of the specific 501B you got; they sell them with different modules, and they usually specify how you can drive it.
It was okay, but 3W is just too much all the time ...
XM-L LEDs are 10W, though cheap lights typically underdrive them at 6W due to heatsinking issues. Single-mode-driving a XM-L at 3W doesn't make a whole lot of sense.
It started but the board soon shutdown, and now it's a lot dimmer, then i opened it up and smelled smoke Must have shorted the led out and killed one of the AMC7135's
It probably got badly overheated. I'll copypaste here what I recently posted on
Daniel Rutter's blog about the 501B and other flashlights using the P60 drop-in modules:
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- you can't make any assumptions about the voltage of the drop-in. Some can take anything from one primary CR123 to four 18650s (losing some efficiency to the multi-voltage regulator), others are made just for one LiIon and won't even run from a primary; if they're also too hot for smaller cells, this restricts them to just one 18650. Look at the product page; if that is not available experiment with a variable power supply (and cross your fingers).
- most have lousy heatsinking. I have no doubts that SureFire bodies mate perfectly with SureFire dropins and transfer heat well (you'd want them to, for the money), but Chinese bodies and Chinese dropins come in all sorts of slightly different sizes. Often the only thermal contact you can expect them to make is through the terminal springs. A 3W LED might survive a decent time in there, but I've seen things like nine-watt MC-E LEDs in dropins that had a big fat insulating layer of air between themselves and the rest of the body. *shudder*
- This problem can usually be made less terribad (I'm fond of the word "terribad", by the way) by wrapping the dropin in aluminium foil until it solidly contacts the outer body. This is far from an optimal thermal solution, but a damn sight better than nothing at all. Still wouldn't run a MC-E like that, though.
- Even then, the surface on which the LED sits is often dangerously thin. The same MC-E dropin I mentioned earlier has a laughably thin "bottom"; even if it had perfect transfer with the outer body, it's far too thin to effectively transmit to it all the heat from the LED.
- If you happen to have a P60 light with lousy heatsinking and a weak LED and would like it to make MOAR light, a cheap and effective solution is
this. Incandescents don't much care about heatsinking and this particular one makes rather a lot of light; it's inefficient compared to LEDs, of course, but with a beefy 18650 powering it that's not much of a problem, and it's very cheap. I put one in the flashlight that originally housed the aforementioned MC-E dropin and it's been my light of choice in the rare occasions when I need a beam colour that doesn't make everyone look like zombies.
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