2 X CR123 P60 w Most Lumens Output

I notice that many good D26 sized drop ins are really built for Li Ion batteries. They either have a 4.2 volt max that might toast the emitter with primaries or 9 - 12 volt max that 2 X CR123 cannot fully power.

I wonder which drop in will actually produce the most lumens safely with 2 X CR123. Some have drivers that will UNsafely overtax the primaries as their capacity diminishes. Others simply don't have much output with only 6 volts.

I don't care about flat regulation so if direct drive is safest and brightest that is fine with me.

I expect the one with the most output will be an LED but if there is a 6 volt incandescent drop in with more output on 6 volts that is fine too. The key is you cannot simply look at some of our charts that show max output with 8.4 volts and expect 2 primaries to produce similar output.

This is about lumens - not throw. Cool white tint is fine but not a major criterion.


This IS different from 50 other threads on brightest P60 because I am restricting it to 2 X CR123 primary only.
Any suggestions?

For 6 volt, and floody is fine, I'd go with a custom made Nailbender Sst-90. He can make it direct drive but that's more for 18650 batteries. Specify battery type and number of modes.
Get an ucl lens and a low resistant tailcap and it'll be wicked bright.
My Nailbender Sst-50 singlemode was 550 lumens, P7 is about 500 lumens.
XML will probably be around 550 lumens too at 3 amps.

The sst90 is the way to go I think

Thanks for replying! Some folks have claimed that the driver Nailbender uses tries to draw too much current from primaries as they lose capacity and that it could even cause the batteries to vent. I know Nailbender says they are safe and that has always been my experience but I'm no expert on drivers.

Nailbender can also vary the draw. I usually choose 2.8 amps. Is that too much for primaries to handle? Could I get away with 3.2 amps too?

I'm pretty sure I read somewhere on here that an XM-L driven at 1.2 or 1.4 amps has an output of 450 lumens. That would be safe on primaries I think.

EDIT: I remembered what I read.....the Quark Turbo X specs.(XM-L)
Here they are.......
Typical Output Levels and Runtimes + (LED drive current)

Moonlight: 0.3 lumens for 20 days, (1ma)
Low: 8 lumens for 2.6 days (10ma)
Medium: 60 lumens for 13 hours (50ma)
High: 260 lumens for 3 hours (250ma)
Max: 450 lumens for 1.5 hours (990ma)
Strobe: 450 lumens for 3 hours
SOS: 450 lumens for 6 hours
Beacon: 0-450 lumens pulse for 15 hours

2.8 amps is safe for sure, I think at 3.2 amps you'll have to turn her off from heat before draw becomes a concern.
With my sst50 I've run through 6 sets of batteries and never a problem. I've run the following primaries; streamlight, surefire, and energizer through it. Never more than 10 min at a time, and the nailbender has been solid.
My guess is I have the 2.8amp driver, and I've never heard any horror stories about nailbenders hurting cells so I trust when he says it'll handle it

Nailbender is your best bet. He's sent me 4 of his P60 dropins so far, each of them with the 2.8A driver and each of them regulated. I've run all 4 of them on CR123A primaries without issue (though I use 18650's with them now). I think 3.2A is pushing your luck though.

If you're looking for flood over throw, an SST-90 or XM-L would fit the bill. Maybe a Linger special with two High CRI XP-G's? :devil:

As stated before in previous threads the max "safe" sustained current draw is 1-1.5A for a cr123 primary. Nailbenders 2.8A driver uses AMC7135 linear regulators (CPF search for it). Ideally you need a buck driver like the one in a Thrunite XM-L module.

2.8 amps is safe for sure

Click to expand...

In short bursts maybe.... too risky IMO for safety.

http://www.candlepowerforums.com/vb/showthread.php?67078-123-Battery-Shoot-Out

But if a single cr123 can handle 1.5 amps wouldn't 2 batteries divide the 2.8 amp draw to 1.4 amps each?

But if a single cr123 can handle 1.5 amps wouldn't 2 batteries divide the 2.8 amp draw to 1.4 amps each?

Click to expand...

If it was a buck circuit yes. Thats why I stated earlier to do a CPF search on the AMC7135 linear regulators (not a buck circuit).

The trouble is the thrunite isn't driven hard enough and 6 volts wont produce full output in the high voltage model.

Other candidates?

On the above link on batteries, he drew 2.5 amps of a single cr123 and no I think the shining beam drivers for two cells he uses would be safe ?

calipsoii said:

If you're looking for flood over throw, an SST-90 or XM-L would fit the bill. Maybe a Linger special with two High CRI XP-G's? :devil:

Click to expand...

I sold my 3-mode neutral Linger and ordered a single mode High CRI Linger to replace it, BEST FLOOD LIGHT EVER IMO (especially with the diffused lens)

I'm not looking for a flood light. In order to remove arguments about lux vs lumens I decided to go with lumens. If two lights have the same lumens I would choose the one with the brighter hotspot. Although the vast amount of usuage seems to indicate the driver nailbender uses is safe with primaries I'm going to err on the side of caution and continue to use li ion with my high output nailbrnders.

This returns the subject to the original topic. Since I know little about drivers I will accept the theory that it is best to use li ions with the nailbender 2.8 amp drop ins. What would be ANOTHER high output P60 that IS safe with primaries?

That brings us 2 amps or less? The Thrunite XML 3-9v it's run at 1.5amp so regardless of driver it'd be safe for cr123's
Mmm the Malkoff M91 XML may be able to run on two cells ?

With the right driver 2 amps should be fine but the Malkoff is really designed for 3 x cr123. The 2.5 amp Dereelight pill is also designed for 3 x CR123.

I think it is a shame nobody is building a safe, high output xml P60 that is designed especially for 2 x CR123.
Testing has shown there really isn't much difference between the output of the 1.5 amp Thrunite R5 and the 1.5 amp Thrunite XML.

I wonder how hard it is to assemble one. IlluminationSupply sells all the parts.

The thrunite XML is only 100 lumens (if that) more than the xpg. Only noticeable side by side comparison, definately not worth it with the hotspot size difference.

With the knowlege and the tools and skills to use them it is doable....but I have none of the above!

Part of the problem may be that nobody builds a good driver for 2 amps at 6 volts.

Solarforce makes a 5 mode 3-6V XM-L drop-in and a 1 mode 3-6V XM-L drop in. These are supposedly designed for 2xCR123 use. I recently ran a pair of Surefire CR123s down on max in the 5 mode. Things did get quite warm (Solarforce L2 host) but never too hot to handle.

Trouble is output is even less than Thrunite. I'm looking for something that draws at least 2 amps at the emitter.