L1 head on E1E/E1L body?

I just tried to put my L1 head on my E1E body, and it fits! Now, is it safe to run the L1 head with the E1E body? Am I getting the high mode now?
This could really be a nice way to play lego if its safe to runt it like this!

I have run the L1 cree head this way on a primary w no problems, didn't even get warm. Looked like high or close to high mode to me. I'm sure it will probably work with a 3.0v rechargeable too. I wouldn't try a 3.7 cell though, you might cook it.

L1 head contains no electronics, just the emitter, and it will be direct driven if the head is slapped onto an E-series body. Depending on the battery (primary or li-ion), its state of charge, and characteristics of the individual LED, it could be underdriven, it could go *poof*, or anything in between. Definitely not safe.

I thought the electronic stuff was moved from the body to the head? since the new L1 got a smaller body than the older?

FlashSpyJ said:

I thought the electronic stuff was moved from the body to the head? since the new L1 got a smaller body than the older?

Click to expand...

No, the electronics is still in the body. They changed it from a "coffin style" (PCB mounted lengthwise, like in the L2) to a "sandwich style" (small round PCBs sitting perpendicular to the axis of the body).

Aha! Ok! Then I wont be using the E1E body then! Good to know! Thanks!

It's okay as long as the draw isn't over 1.0a, which I don't believe it is. I did this this the head of a Milky ML1 and Scott said it's fine as long as it's not over-amping. I measured it at something in the 0.9x range.

Again, this depends on forward voltage of the LED, internal resistance of the cell, etc. BTW, your DMM has some rather significant internal resistance, too. Without the meter in the circuit, actual current will always be higher than measured. Just don't do it.

it doesn't hurt the LED if you just use a 3v CR123, just DDing, which actually give you the best efficiency out the cell. the LED will last longer at that voltage.

use at you own risk with 3.7v R123.

FlashSpyJ said:

I just tried to put my L1 head on my E1E body, and it fits! Now, is it safe to run the L1 head with the E1E body? Am I getting the high mode now?
This could really be a nice way to play lego if its safe to runt it like this!

Click to expand...

I just tried this, Cree L1 head on an E1e body, and you are definitely not getting the high mode. Probably around 30 lumen.

I'm currently doing a runtime test with an L1 Cree head on a E1L body ("E1L1"?). I started the test on 10/13 @ 9:45 PM. It's now over 19 hours into the test, and it's still putting out usable light. Present output is much greater than my Gen2 L1 on low (advertised 1.1 lumens). I would guess around 5 to 10 lumens. Battery was a nearly new SF123A. I agree with 700club that it was not putting out high mode initially, and 25 to 30 lumens sounds about right. I don't have any way to measure lumens, but output definitely decreased steadily. The head is not warm at all.

I'll post another update and maybe some pics after dark...

I have been running two different old style L1 heads (both ML1's, one UW0H, one SSC V0) on an E1E body with 3.7V RCR123 for a while now. I run it with a McGizmo McE2S two stage switch, so I use it on low 80% of the time. Hight for fun, not usually necessity. I have run it at most 15-20 seconds on high at a time. It has worked fine for me with no problems, but it is still a risk and YMMV.

I used it yesterday in a corn maze just north of Detroit, and I got lots of "nice light!" complements when I used it on LOW (22ohm McE2S SSC version, though my UW0H Lux3 Milky mod is also very bright) as it blew away everything else out there lighting up signs and maps in the maze with its wide flood optic. On high (est. just under 200L) it was too bright to look at anything up close as it would totally kill your night vision. I still had to be careful with low so as to not relect the beam back at me.

Running it conservatively on CR123 primary or 3.0V RCR, it is a decent long running light. I'd guess around 25-35L too. It's great for camping on 3V, so I have a very low low for in-tent use and high is still enough light for everything else and runs a loooooong time.

The old style L1 SSC head on E1E body and McE2S is one of my top 3 favorite lights. SSC'd Gladius and HDS EDC U60 are the other two.

Distance to the end of hallway is 20 feet.

Fresh CR123A:


2 hours, 53 minutes into test:


at 24 hours, 23 minutes:


I'll update this post with a pic from a fresh cell after the test.

at 48 hours, 3 minutes:



It's now putting out less than my Gen2 L1 on low, which means less than 1 lumen, so I'll quit the test here.