Surefire 9P + 1 Cell extender + 2 * 17670 + P90 = Poof?

[Chongker]

Hey guys, been on this forum for a couple of months now, though I don't post much since just reading other threads seems to be good enough to answer most of my questions.

My question is just as the title says. I recently got myself a 9P along with a cheap 1 cell extender off ebay and a couple of cheap 17670's from DX as well. I was thinking of starting down the road of incan's (like the tint) and didn't wanna blow my meager budget to pieces, since primary CR123A's are real expensive here in the UK ($48 for a dozen SF batteries!). The most logical solution was of course rechargables.

So here's the story. Got batteries, charged 'em and let 'em sit for awhile. Got 9P with extender ready. Drop in batteries, screw on tailcap and wow! (well sorta, wasn't that much of an improvement over the G2) Worked well though, guilt free lumens and a pretty bright torch. Things were going well for a few minutes, so I decided to try taking it out for abit. Was walking along in the dark on a smallish road in the countryside (live in the country ) and then suddenly There goes the bulb. To check it wasn't the batteries, I switched back to 3 CR123A's but with no result. The bulb's a gonner. Didn't expect this to happen as i've read on other threads that it should run fine on 2 li-ion batteries.

Is there something particularly wrong with the set-up I had? Got an LF EO-9 on the way, and want to know if it'll be alright to run it on 2 17670's like I had for a little while with the P90? Sorry for the really long post, this was meant to be a short question ~1 paragraph long, but ended up telling almost my entire 2 month flashaholic life .

TIA for any input!

 

[thermal guy]

The P90 is only a 6.5 Vt or something like that.2 17670 are what Almost 8 Vt.

 

[Nitroz]

The P90 is only a 6.5 Vt or something like that.2 17670 are what Almost 8 Vt.

The Surefire web site says that you can use the p90 in the 9p, the 9p uses 3 cr123s. That's 9 volts, so 2 17670s should be ok.

 

[cfromc]

I used a P91, which is more like a ~6.5V bulb, on 2 18650s without any problems. The P90 should last even longer since it is over a ~7V bulb. The EO-9 should work fine. The fact that the P90 wasn't much brighter than a P60 was the bulb's way of telling you it wasn't long for this world. It should be significantly brighter running on 2 l-ions.

P.S. Do yourself a favor and save up for some good l-ions like AW's. You will end up saving money in the long run.

 

[Tekno_Cowboy]

Overheated bulb maybe? I usually run a LF HO-9 or EO-9 in my Surefire 9P, running on 2 Ultrafire protected 17500's.

 

[Chongker]

Thanks for the replies guys.

I would have thought using 2 li-ions would have been ok as the voltage sag should have made it quite similar to running a P90 on 3 123A's. Maybe I had a dud P90? Doubt it's overheating as I ran it in short bursts while I was out, just when I really wanted to see something in more details (which my Arc AAA can't reacH :laughing.

cfromc, you don't think it could be because of the cheap cells do you? cos otherwise I've wasted some money on these things (although they work fine on LEDs). Probably will get some of AW's once more money starts to flow in

 

[tazambo]

Your setup has work fine for me for over a year, I'd have to have 4-5 hours on my P90 and nearly the same on a P91.

? bad bulb ?

Regards
Dave

 

[cfromc]

Thanks for the replies guys.

cfromc, you don't think it could be because of the cheap cells do you? cos otherwise I've wasted some money on these things (although they work fine on LEDs). Probably will get some of AW's once more money starts to flow in

I doubt it, more likely a bad bulb. I had a couple cheaper cells in the past and after a few cycles they started charging and discharging at different rates. I really had to watch the charger and pull one cell off before the other. I also checked the voltage after long runs and just periodically through the discharge cycle. I currently have AW 17500s and a P90 and it is very bright, more than a P90 off of CR123s and noticably brighter than a P60 on 2 CR123s. Use the cells you have for now, just make sure you don't go over 4.2V when charging and check the cells once in a while to see if they have close to the same voltage during use. I've heard that beyond .5V difference is asking for trouble. I like to keep them within .2V though.

 

[Chongker]

I doubt it, more likely a bad bulb. I had a couple cheaper cells in the past and after a few cycles they started charging and discharging at different rates. I really had to watch the charger and pull one cell off before the other. I also checked the voltage after long runs and just periodically through the discharge cycle. I currently have AW 17500s and a P90 and it is very bright, more than a P90 off of CR123s and noticably brighter than a P60 on 2 CR123s. Use the cells you have for now, just make sure you don't go over 4.2V when charging and check the cells once in a while to see if they have close to the same voltage during use. I've heard that beyond .5V difference is asking for trouble. I like to keep them within .2V though.

Thanks, i'll take that advice. Have a DMM myself and always check the voltage of the cells before putting them in any light, especially one with multiple cells. Took the ones I used with the P90 off a little early actually. Came off at 4.13V each and both settled to ~4.09V after awhile. Did this as a safety measure specifically not to overdrive the bulb. Still went though so most probably was just a bad bulb.


I was hoping to get the results tazambo was getting, nice long run times . Oh well, looking on the bright side, my EO-9 came in the mail today! (pun intended). Man this thing is bright . Quite noticably brighter than the P90 while on CR123A's, but have yet to try it with li-ions. Shall do it tonight when it gets dark enough!

Cheers all

 

[thermal guy]

Se what the experts say.I thought as you about the bulb boy was i wrong.

http://candlepowerforums.com/vb/showthread.php?t=197508

 

[Chongker]

Hello,

thermal guy, thanks for the post :thumbsup:. I'd already read that thread before along with many others, just to make sure I knew what I was doing when I got into incans with li-ions. From what I understand there, the P90 whould not have been too badly overdriven especially since I had both cells at slightly less than full capacity.

The fact the my new LF EO-9 can take the exact same batteries and run totally fine with them, even with a lower voltage rating, shows that I probably just had either an old or bad bulb as cfromc and tazambo said.

Doesn't matter now anyway, the EO-9 blows away the P90 in terms of brightness, so i'm happy :twothumbs.

Thanks for all the info everyone!