P91 bulb blows up on 2xPila 168s

[jte]

Hello CPF'ers /ubbthreads/images/graemlins/smile.gif,

Last night I tried running a P91 on 2xPila 168s, and the bulb blew up after a couple of secs of bright white light. The host was a Vital Gear 3x123 body with a 123 extender, an E-to-C adaptor and a C bezel.

Have had no problems with 2xPila 150s on P90 in the same host type (without the 123 extender, obviously).

Now, brock's page says:

P90 7.35V 1.15A
P91 6.25V 2.35A

So with an amp draw of 2.35, I figured it was wiser to run the P91 from 2x168s instead of 2x150s.

I realize that 2 Pilas equal a voltage of 7.4, and that this probably means that the bulb was overdriven. But both Pilas and primary cells like the surefire battery have higher voltage when they're fresh, don't they? So, if the P90 can handle the extra "off-the-charger-juice", why can't the P91?

I've read suggestions from people on using 2xPilas to run a P91, and a few actual (and successful) usage reports that say that is works on 2xPila 150s - but is there any reason it shouldn't work with 2xPila 168s?

Anyway, have anybody else tried what I tried, unsuccessfully or successfully?

If I wanted to get more lumens on 2xPila 168s, I could use the Pila 9V bulb in a C bezel, right? This lamp should output 130 lm instead of the P90's 105 lm.

Thanks.

 

[FlyUSArmy]

Re: P91 on 2xPila 168s blows up

I run a P91 off of two Pila 150S in a Z3 body.

The 168 should just have higher capacity. Bulbs occasionally just blow. I think perhaps it was just a bad bulb.

I have had sucess with both the P90 and P91 lamps on Pilas.

 

[Hoghead]

Re: P91 on 2xPila 168s blows up

Are you sure you didn't put a P60/P61 in by mistake?

 

[jte]

Re: P91 on 2xPila 168s blows up

FlyUSArmy: Hmmm.. guess I'll have to try again then. Next time I'll test on 3 surefire cells first to see if the LA actually works.

Hoghead: Oh yeah, I'm sure /ubbthreads/images/graemlins/smile.gif. Also, I remember the band on the lamp being yellowish, like it's supposed to:

http://www.surefire.com/maxexp/main.pl?pgm=co_disp&func=displ&strfnbr=6&prrfnbr=244&sesent=0,0

Anyway, don't you think that an amp draw beyond 2C will punish the 150s too much? I thought I'd read somewhere that 2C (ie. for 150s: 2x1A=2A) was max for Pilas. That's why I ran the P91 from 2xPila 168s.

By the way, do all SF lamps explode when they stop working, or do some just "fuzz out"? What is the general rule (StreamLight, Pila, SureFire etc.)? I mean, in the lamps with fixed reflector, the reflector can get damaged over time, not even considering the lens which always gets blasted.

 

[cy]

Re: P91 on 2xPila 168s blows up

welcome to cpf

PLEASE EDIT YOUR TITLE TO REFLECT BULB BLOWING UP

from your title, it apears Pila's blew up, if you don't know what P91's are. lot's of us are hyper sensitive about possibiblity of li-ions belowing up.

 

[jte]

Re: P91 on 2xPila 168s blows up

cy: Thank you and point taken. The deed is done /ubbthreads/images/graemlins/smile.gif.

 

[CM]

Re: P91 on 2xPila 168s blows up

Bulbs blow up with some regularity. I suspect that they would have blown up regardless of the power source--ie. 3x123 or 2 Li-Ions. The bulb might likely have been on its last leg. We sometimes attribute effects happening to an event that really did not cause the effect. I've run 9V Surefire on 2x18650's with no dire consequences.

 

[cy]

Re: P91 on 2xPila 168s blows up

jte, the post is edited, but the title needs the same

thanks,

 

[Hoghead]

Re: P91 blows up on 2xPila 168s

The P91 shouldn't blow on two Pila 168s. I think it was just time for the P91 to blow. If this was a new lamp, it was defective.

There have been a lot of 9 volt Surefires running great on two Pilas, either two 150S in a three cell body or two 168S in a four cell body. I think there are more people using three cell bodies than four cell bodies because three cell bodies are cheaper and more readily available.

I would just put in another P91 and enjoy.

 

[jte]

Re: P91 blows up on 2xPila 168s

cy: I thought I did it right. I don't know what to do to fix the title if it's not about changing the original post. Could you give me a pointer? Sorry, this is my first post.

Hoghead: The lamp was spanking new. But I'll just try a new one. Thanks.

 

[Hoghead]

Re: P91 blows up on 2xPila 168s

[ QUOTE ]
jte said:
cy: I thought I did it right. I don't know what to do to fix the title if it's not about changing the original post. Could you give me a pointer? Sorry, this is my first post.

Hoghead: The lamp was spanking new. But I'll just try a new one. Thanks.

[/ QUOTE ]

re: title, I "replied" to your origional post after you changed the title. Look at the title of the different replies to your origional post.

 

[jte]

Re: P91 blows up on 2xPila 168s

Hoghead: I totally get that, but I can't see how I can edit the posts done by others. I mean, the point is that the posts done in reply to my post has the wrong title, right?

How do I change other people's replys? I can change mine, but not yours.

Sorry, I must be slow.

 

[Hoghead]

Re: P91 blows up on 2xPila 168s

No, you're not slow. You can't edit other people's posts.

I'm not sure what cy meant for you to do other than what you did to change your original post and what I did to get the title to appear farther down in the thread.

 

[jte]

Re: P91 blows up on 2xPila 168s

Right then. I just hope I did it right. I really don't wanna attract negative attention or start a panic about more li-ions blowing up on my first post.

Thanks, hoghead /ubbthreads/images/graemlins/smile.gif

 

[KevinL]

Re: P91 blows up on 2xPila 168s

/ubbthreads/images/graemlins/rolleye11.gif

(*whispers* I think cy has a point though /ubbthreads/images/graemlins/grin.gif)

I ran a P91 off two unprotected 18650s for a short while (equivalent to the Pila 168A without the protection circuit) - this configuration is *NOT* recommended, but the P91 got away with it.

 

[jte]

Re: P91 blows up on 2xPila 168s

KevinL: Yeah, I know you had some bad experiences ..

Anyway, I tried running 2xPila 168s on a new P91 last night, and it worked just fine.

Thanks for your help everyone /ubbthreads/images/graemlins/smile.gif

 

[cy]

Re: P91 blows up on 2xPila 168s

jte, if you want to add the word bulb to title, go to your first post and edit the title. you are the only one that can edit, besides the admin's.