New P3X Fury - initial draw off new SF primaries 3.9A

Hello,

I have a new P3X and have been very impressed with the light. I was checking my batteries today and dropped three brand new SF 123 primaries into the P3X.I did a tailcap current draw test and was surprised to see a starting draw of 3.90 A!After 60 seconds, the draw had ramped down to 2.0 A.I thought this was too high and that I must have a bad primary, so I swapped in three different new SF batteries, with identical current draw results.Other tests I've seen online of the P3X showed a starting current of 2.4A off primaries and then a ramp down to closer to 1.5A over 60 seconds.I emailed SF customer service as this initial draw seems a bit TOO ambitious for primaries, haven't heard back yet.Thoughts? Am I worrying about nothing?Lithium batteries are serious business so I'm a bit reserved to push them at almost 4A's , even if it's only for 20 seconds!


PS:confirmed my fluke meter was good by checking other lights (Malkoff's) M61's which were right on the money at 600mA off two primaries.

I did some searching online and from what I can tell the maximum continuous current of 1.5A is to obtain 50% of rated capacity ~ half of about 1500mAh. One document I found list the short circuit current of a Tenergy CR123A as 12A. I have seen pulse current listings on various brands of around 3500mA. What I haven't been able to find so far is an exact definition of pulse current when used in this regards. I would assume the pulse current has a duration and an impact associated with it, such as a time and what impact that has on battery capacity or safety.

Surefire batteries seem to provide better results in test from what I can tell based on threads in this site, so I would assume they have a higher rated capacity based on current draw. According to Surefire's web site their batteries have built in heat/fault protection. Being that Surefire specs out their batteries, I find it unlikely that they would be running their batteries at level that would present a problem. Given the ramping function used in the P3X I would assume the current draw drops off fast enough that it has minimal impact on capacity and the built in protection should prevent any safety issues.

Anyway this is what seems to be the case based on what I can find. If you really want to put your mind at ease just give Surefire's technical support a call and see what they say. I would assume, they are going to be the best source to give you the details you are looking for.

Thanks for the replies. The thing that stumps me on this is that, per the datasheet, the Cree XM-L is rated at a bit over 1000 lumen at 3A & 3.35VDC. Basically it puts out 1000 lumen for 10 Watts. With a buck regulator that's about 80% efficient, the P3X should be pulling about 1.4A off the batteries, not over 2.5X that! Either the regulator is very inefficient or the LED is way overdriven at startup, way more than 10 Watts and more like 25 Watts!