Run time for Pilas w/ P61 HOLA?

Couldn't find a link for this, but how is the run time of an SF flashlight with a P61 HOLA compare with the P60 using Pila 150s (assuming a standard 3x CR123 body)?

Runtime will be about 0.001 sec.

No seriously, the P60 & P61 are 6Volt lamps, meaning that if you drive them with 2x150s (7.2V, give or take) will flash them.
The P90 & P91 however, will work fine.

I think mokona2 meant P91 since he mentioned 3x123
In this case run time will be less than 25 minutes.

Oops.. my bad. I messed up the part numbers.

So P91 w/ 2x 150s will be about 25min? Will that mean slightly less output versus P91 w/ 3x CR123 at less than 20 minutes?

I believe the output is about the same with 2x150s, also the output is more stable.

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StEaLtH_ said:
Runtime will be about 0.001 sec.

No seriously, the P60 & P61 are 6Volt lamps, meaning that if you drive them with 2x150s (7.2V, give or take) will flash them.
The P90 & P91 however, will work fine.

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mokona2, short answer is that I don't know...sorry.

fivemega is correct about his assumption, however it's not all that simple.

StEaLtH, you are making the common mistake of thinking that 2 nominally rated CR123 primary cells are 3v each, and therefore the bulbs are the same. As SureFire guru Size15's has stated before on the who makes SureFire batteries thread, SureFire has/had on board, a battery expert who knows the characteristics of 3v Li-primary cells like the back of his hand.

Answer to the SF LA's is that it depends, and given known characteristics of 123's under specific bulb loads of voltage and amperage, the SF LA's are tailored to run in overdrive mode. Each SF LA has a different voltage/amp bulb tailored to the desired amount of output/overdrive.

Take a look at SilverFox's tests under 1 & 2amp loads of Lithium primaries 123 Battery Shoot Out, then look at various SF LA on 2x123 & 3x123 lights on the 2nd chart of Brock's page Brock's Regular Flashlight page. Notice the difference in voltages and amps each LA is running at, compare to SilverFox's tests. M6 HOLA must be an 6v or lower bulb, yet how many 123's are run in series on this? The P60 causes the 123's to sag in voltage down to about 4.8v at a 1.1a current drain, if the P60 had a 6v bulb in it, the color would be very yellow. The P61 puts even more stress on the limited capability of the primary 123's (Pila as well as other Li-Ion, generally speaking can supply a little more voltage under similar loads) such that under 2.3a bulb, voltage sags down to 3.75v...can you imagine how yellow and dim a 6v bulb would be at 3.75v!

FYI, I run the M*g 6-cell xenon bulb at near instaflash levels, ultra white light output, on 8aa in the 8AA-2D adapter that fivemega is running out off shortly; in a M*g2D. Consider the Pilas are nominally 3.7v and come off the charger at about 4.1-4.2v. 8.4v is not that much of an overdrive to a 6v bulb. They might instaflash a 6v bulb, but it would depend on how thick the filament is, amount of 'pre-overdrive' the bulb is designed for at the rated voltage.

My guess(and it's just a guess) is that the P91 draws too much current for the smaller Pilas to compensate for, and the voltage drop will be such that voltage will probably be either less than the 3 x 123's (making for an expensive disappointment /ubbthreads/images/graemlins/frown.gif ) or about the same. Instaflash is very unlikely, as initial voltage from 3 x 123 = 9v vs. 8.4v from 2 Pila. For a 2.3a load, those smaller Pila's are going to have trouble getting to 25min., I'll bet you get 20min max, and more rapid yellowing at this higher amp load.

It is possible (I am almost positive that the lower capacity R123's tested so far; run 3.5v once a load is placed on them, 3.7v is the nominal unloaded/very small amp load rating; at the start, and drop from there down to 3v where they need recharging) that the P90 could also disappoint.

If the Pila's start at 3.7v with a 1.1a load from the P90 that's only 7.4v, or the same as 3 x 123's under that load. But if Pila's start at 3.5v, you begin with the P90 at 7.0v and drop down to 6v by the time they need to be recharged. Capacity of Pila 150's is less than CR123's at loads below 1a, so I would expect shorter runtime, but less severe yellowing up to the point the batteries need recharging, because the Li-Ion's discharge curve is slightly flatter than the primary lithiums. How much of a difference this is, I don't know. How much this affects your dislike or like of one battery system over the other is personal preference.

Who makes SureFire 123 batteries?

Thanks udaman,

Wow, so many details to learn about. I'm more partial to off the shelf CR123s rather than rechargeables, but this is still something to consider for the future if I plan on using HOLA lamps on a daily basis.

mokona,

Based on my informal comparison of the P91 on three Surefires or two PILA 150S the Pilas provide a longer bright burn before yellowing. Two 168S in a Balrog Be4 (plus Speck E2C) will give an even longer bright burn.

I now use PILAs in all my 3 battery Surefire incandescents including the D3/9P with the SRTH/N2. I would love to bore out a 3 battery Surefire body to take two PILA A cells but Don (McGizmo)said that the deep o-ring groove makes this unworkable because of the resulting paper thinness at the o-ring. The streamlight TL-3 will work beautifully on 2x150S but unfortunately the barrel is about 3/8" too short to make this practical.

Brightnorm

Plenty have posted that the P91 and 2 Pila 150s setup works great. If your Pila's are new though, maybe discharge them a few times on the P90 first to "break them in" for the current draw of the P91. /ubbthreads/images/graemlins/cool.gif

I had very good results with the P90's and p91's with pilas. the 150s's provide 22 minutes of almost regulated-like bright light in the P91 and over 45 minutes of bright light in the P90, in my runtime test. I like how the pilas work in the 3-cells much better than the CR123s. Those who don't use the pilas don't know what they are missing.

If you bore out the inside of your Surefire, you can use the higher capacity 150a's. Worth the extra 10% or so of extra runtime, not to mention your light will stay "whiter" longer.