L1 Head on E2 Body?

Ok I've tried searching around, with mixed results, so I figure I'll start a new thread.


I just got my L1 yesturday, and I got to worndering if the head would fit on my E2W, mainly so I could see if I would like having an HA/Black head on it to go buy a KL1 (not sure if I like it or not, doesn't look terrible, but not great either)

Well I did turn the light on for only a second or 2 the LED lit, didn't appear any brighter than off the L1 Body on high, I've lit the LED off the 6V a couple of times now for a second or 2, and it's now back where it belongs on the L1 Body.


I'm mainly wondering for curiosity's sake, and knowing what my lights can/can't do. I have no reason to move the head to the E2W as doing so would leave me with a useless L1 Body/Tailcap.


However after reading some old posts this morning that the LED would likely go poof on a 6V body, I found myself scared that I was "dumb" enough to try to light the LED off 6V, but thought, I'd do some testing.


So I grabbed my 2 multi-meters, and set one for DC Volts, and the other to Amps. Took the head off and turned the light on... I was surprised at what was comming out of the converter.....


I get on low 3V .22Amps with my 2 meters
on HIGH I get 6V 1.15A

So now I'm left wondering if the LED isn't designed to run off of 6V similar to say an R/S/T Vf bin on the LED, or that perhaps theres something else going on?

One meter gave me an 18.6-18.8ohm reading (once almost 19) when set to the ohms, and the positive lead on the back of the LED assembly, the nedative near the threads... it was on my little Radio Shack pocket meter, auto range, couldn't get any ohms reading from my larger meter.

I'm not good with all the electronics stuff, not even sure how to use the information I got.

But mainly curiosity has gotten the better of me and wondering now... I love my L1 the way it came, and wouldn't really change a thing (unless I came across a spare head for cheap, which I'd mod, or try) And wouldn't put the head on my E2W other than again just to see if I want a KL1 head for the light, and can live with the color differences. But after reading that 6V through the LED would fry it instantly, and seeing mine survive a couple short burts, and seeing 6V (no load) come out of the end of the light, I'm now scratching my head wondering.

Ok further information, I didn't realize when doing my resistance the meter has an "M" next to the Ohms symbol when reading around 18.5-18.8ohms

Also removed the tailcap and did an Amp draw test from the back, and got around .8Amps

I don't think a LuxIII can survive direct drive from 2 Cr123s...

Willabbott said:

So I grabbed my 2 multi-meters, and set one for DC Volts, and the other to Amps. Took the head off and turned the light on... I was surprised at what was comming out of the converter.....

I get on low 3V .22Amps with my 2 meters
on HIGH I get 6V 1.15A

Click to expand...

On low the L1 is not regulated. Many L1 owners can confirm that low mode actually disappears first as the battery runs flat. You are simply reading the voltage of a single CR123A cell through a small resistor.

On high the L1 drives through a regulating circuit. It boosts the voltage of the cell up to a point high enough to get the desired current flow. Typically, the head of the L1 would be installed and the current flow would be satisfied long before the voltage hit 6V. However, you disconnected the head and are essentially running the convertor "open circuit". Apparently, Surefire designed the L1 convertor so that it stops at 6 volts. Some boost drivers will keep boosting the voltage in a futile attempt to make their current, and wind up frying themselves. I'm not sure why you're getting such a high current reading, and I'm suspicious of whether or not that is truly a valid reading. Six volts at 1.15 amps is nearly seven watts. That's a rather beastly load to pull from a single CR123A cell, and I'm pretty sure it can't keep that up for long, and I guarantee you will never see that kind of power actually delivered to the L1 head.

You cannot accurately measure the forward voltage and current without having the LED installed in the circuit.

Thanks!

I knew there had to be some logical reason... I kinda wondered about if one could truly test the voltage, etc... I suppose it's possible, I just need to make sure the circuit is complete, by putting my multimeter inline say on one side (positive or negative) and installing a jumper (which I just bought a bunch of yesterday for testing LED's) on the opposite side, then I could measure whats actually flowing through the circuit.. Will have to try that and see what numbers I get.

Ok I hooked a jumper on the negative side from the body to the head, and put my meter inline on the positive side.


I got .42Amp and 4.9V

I'm too scared to try it on the 6V assembly again, but would be curious to see the Amp draw.

[EDIT] I did put the head inline off the E2 body for mere seconds, only tested Amperage and for mere seconds it climed right up to 1.8Amps (OUCH!) I dare not keep it on long enough to let the reading stabalize... so I'm guessing the LED can survive a short burst or 2 but not for any serious use...

Still the head will work good for me to just put it on the E2W long enough (without lighting it) to decide if I want an KL1 head (or similar) and can live with the black or HA colored head on wine colored body.