Need some help with Aleph 2

[Hoghead]

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McGizmo said:
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If there are others who are happily using their BB700/ 5W's with Pila's they are not coming forward and putting any weight on the other side of the scale here! /ubbthreads/images/graemlins/icon3.gif

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I've been using a Pila 168S with a PR/X3T/BB750 that JollyRoger built for about a year with no problems.

I usually use it for less than 5 minutes at a time, but I've run it for 10 to 15 minutes a few times. This might not apply because this is an older BadBoy. /ubbthreads/images/graemlins/icon3.gif

 

[qballxx]

Chop,
What kind of performace would I see with the 750mA bias, a Lux III and Wiz2 converter running on 1.5X123 body possibly on a aleph 1 head?

I'm looking for something that is brighter then my L4 that I carry daily, so will this setup work for what I'm looking for?

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Chop said:
The "the most light possible" isn't always the smartest thing to do. Output/performance is determined by two things. The size of the reflector, and, to a lesser extent, current. With the McR20 reflector, that is in the Aleph II, 500mA seems to be a sweet spot between performance and runtime. You get something around 1100 lux on a meter and around 1.5 to 1.75 hours of runtime. Going to 1A will get you maybe another 100 or 150 lux or so, but runtime is going to go into the toilet. These examples are based on running a NexGen converter in a 1X123 body. The principles apply to other converter/battery combinations though.

If you want to stay practical AND get almost every little bit of performance, go with a 667mA or 750mA bias, with a Lux III. On the 1.5X123 body, I'd consider using a Wiz2 converter. The Wiz2 will allow you to get regulation on a Pila 150S cell AND 2X123s. If you go with a conservative bias, like 500mA, you should also get decent performance on 1X123, should the need arise.

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[brightnorm]

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McGizmo said:
... I know there are a lot of 5W's being driven successfully with BB's and Pilas but after three failures that I am aware of with no known cause, I have become a skeptic!

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/ubbthreads/images/graemlins/frown.gif Brightnorm/ubbthreads/images/graemlins/mecry.gif

 

[chrisse242]

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McGizmo said:
What current level is the 5W being driven at? If it is 700 or 750 mA, driving it on a Pila could be death to the converter.


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Does this mean driving a BB/LuxV combo below 700mA from Pilas is safe? There has been some talk about the BB/LuxV/Pila issue lately but I didn't find any information about safe current levels.

Thanks, Chrisse

 

[McGizmo]

Chrisse,

Wayne tried to kill a BB on his bench by providing it low Vin with all the power it could pull. He was unsuccesful in doing so. I am suspicious that the anode contact on BN's Pila might be concave and also shorting one of the LED leads perhaps. I have no idea why there have been a few failures?!?!?!? Your answer needs to come from one of the EE fellows here and I sure ain't one of them!! /ubbthreads/images/graemlins/icon15.gif

 

[Kiessling]

AFAIK this isn't known yet since no one wants to invest the $$$ for reliable test results ... /ubbthreads/images/graemlins/icon15.gif
bernhard

EDIT: ooooops ... the master has spoken while I typed ... disregard my babbling please /ubbthreads/images/graemlins/icon15.gif !

 

[Chop]

I've been running BadBoys on Pilas for a while now. Many have assumed, me included, that the failures were due to heat because the BB does get really hot when running on a Pila.

I do, however, have to say that I've never experienced a BB failure due to the use of Pilas.

After reading Don's comments above, it has dawned on me that many are employing various methods of making the rather short anode contact on the battery engage the contact on the bottom of the converter. Some have soldered blobs on their batteries and some have resorted to using small magnet on their batteries. I suppose you could also use some conductive epoxy.

If you are using a method that involves attaching something to the top of the battery, there is always the risk of something sliding around and grounding out on something that it shouldn't be touching.

I use solder blobs on my batteries. It avoids the problems associated with other methods used. Another good alternative is to solder a tall blob onto the bottom of the converter. The problem with this method is that it does away with the reverse polarity protection afforded by the bottom of the can causing the anode contact on the converter to be recessed. If you put the battery in backwards, you're screwed.

What I've been doing on customers' lights is to solder the blob as tall as I can without the blob protruding from the bottom of the can. This works, but if your cell is caved in on the top, it just won't reach.

I suppose it's a matter of picking your poison.

My vote would have to go to a tall solder blob on the bottom of the converter. You just have to remember to put the battery in the right way. I also have to add, that I personally won't do warranty work on a light that dies because the battery was installed backwards.