The ARC4 was really designed to be powered by...

Secondary cells!

Think about it for a minute!

Yes, when the light starts downstepping it is time to replace the battery! Decision time! Do I throw a 123 in the depleted pile so I can run in boost mode? (and potentially waste good supply left to run at lower levels--teens--good enough for many night tasks) With this light you always want to have level 1 available so...

With secondary (rechargeable to the non battery geeks) cells, when it steps you put the battery on the charger and take a freshly charged battery and put it in the flashlight!

I say this now because my secondary 123's from Jon are here and my secondary is 1 and primary is 6 or 7.

I can say leaving the light on at level 1 heats up faster than my L4! The transfer of heat from the LED to the case is quite efficient! (how much is L1 overdriving the 1W LS??!)

Cheers!

I've read that level 1 is around 700mA. But because each unit is calibrated by brightness, id say there would be variations between each ARC4.

Shark,

I too have pondered this. In the case of Arc's that draw current on the high side, the pile of 123's that can't power the light at level 1 should grow pretty quickly. I really think a 2x123 (which can hold a 17670 Li-Ion cell) is a perfect match for the Arc4+. Especially for those that have units that draw on the high side or those very few with the Arc4x's. Unfortunately, but for good reasons, Gransee is delaying the 2x123 bodies until next year. Until then, we need to commission Dspeck or someone with the capabilities to do a 2x123 hard anodize pack for the Arc4.

CM

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CM said:
Until then, we need to commission Dspeck or someone with the capabilities to do a 2x123 hard anodize pack for the Arc4.

CM

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I'll order 1 of those 2 x 123 packs. /ubbthreads/images/graemlins/wink.gif

If you are going to commision something. How about something in between. A battery pack built for the 150s or 150a. It will be a little smaller than a 2x123 pack and a little larger then a 1x123 pack.

I want to collect the set. 2x123,Pila rechargeable,AA,fuel cell,nuclear fusion reactor....

[ QUOTE ]
JonSidneyB said:
If you are going to commision something. How about something in between. A battery pack built for the 150s or 150a. It will be a little smaller than a 2x123 pack and a little larger then a 1x123 pack.

[/ QUOTE ]

While I think this is a great idea (halfway house between 1 and 2x123) it precludes using 2x123 when you need a longer runtime. There is no "ideal" pack, but there are some versatile ones. Me? I would buy both /ubbthreads/images/graemlins/grin.gif

CM

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CM said:
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Me? I would buy both /ubbthreads/images/graemlins/grin.gif

CM

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Ok then - me would buy both too /ubbthreads/images/graemlins/wink.gif

People who use their Arcs intermittently, even those who run on level 1, will probably get pretty close to full amp hour output from their 123s. By "intermittent" I mean typical on time of only a few seconds. That's most of my usage - momentarily casting a beam across a ceiling plenum to see something, throwing a spot into a dark corner when running at night, and so on. The battery recovers between these short activations. When the battery finally dies it REALLY dies. I'm lucky to get a couple minutes of moon mode before my LS completly dies, which is why I often carry a spare battery.

Just to clarify a doubt...

If the battery isn't in the mood to deliver full juice, and the user calls for level 1, does it:

a) not respond, or does it
b) try to deliver level 1, but probably end up only managing the next highest level (level 2, or 3)?

The user'd have to settle for whatever the battery is up to delivering, but there's that bit of disappointment when it can't make full output some of the time.
I suppose the reality is that, even for those that use the light at anything other than level 1 most of the time, level 1 won't be available when they do need it, given the steady drain on the battery. The only way to be certain of the availability of level 1 would be to put in a fresh cell even before the battery is close to flat.

How long before level 1 is NOT available (even for 10 seconds)?

Is this a correct understanding of the 4+?

Cheers.

If you look at Duracell's datasheet, they specify a 123 can supply 1.8A for 3 seconds on/7 seconds off for about 600+ cycles. That's half an hour cumulative time. If your light only draws 1.2A, that time goes up to an hour+. So Dave makes an important point about real world runtimes.

Canuckle,

The answer is b). In a real emergency, you'd be happy to get any light at all. If you must have level 1 at your disposal, then the best thing to do is carry spare batteries. That's why a secondary battery would be useful for a lot of people since they can recharge every night and know they are guaranteed to be able to get level 1 for some amount of time when they need it.

CM

Canuckle,

The answer is (b).

After about two weeks of EDC and using Level-1 boost every so often (just because I could /ubbthreads/images/graemlins/grin.gif ), I was using the light for a few hours of pretty steady Level-10 and Level-4 usage while working on something and then went to use boost mode. The light stepped down to Level-2 when I called for Boost-1. If you didn't notice the step-down, you'd be hard pressed to tell that there was a difference in the light level without a side-by-side comparison or a light meter.

I had some fresh 123's, so I put a new one in just so that I can still get Level-1 when I play. /ubbthreads/images/graemlins/tongue.gif

If I remember correctly, the cell's voltage at that time was 2.82V.

Re: The ARC4 was really designed to be powered by. *DELETED*

Post deleted by Likebright

Re: The ARC4 was really designed to be powered by.

Canuckle, I posted exact timings in another thread, and others have done their own timings. Basically with my Arc4+ Second, leaving the light on continuously, I get level 1 for around 35 minutes, then level 2 for 6-7 minutes, then level 3 for 6-7 minutes, and so forth. Assuming this goes on "forever" (I quit timing when it got to level 7) and that each level uses 70% as much power as the next higher one, that means the light drops down from level 1 when the cell is about 71% depleted. By the time you hit level 4, it's 86% depleted. When you finish level 7, it's 97% depleted. Level 4 is about where the brightness difference from level 1 starts being really noticable. So assuming I have a spare cell in my pocket, I think when the light drops out of level 1, I'd just keep using it, til it got to at least level 4.

In practice I use the light intermittently rather than continuously, which means I should keep getting level 1 until the cell is considerably more than 71% gone. So I'm fine with changing batteries at level 4, leaving 10% or so of the energy in the cell. If I'm using enough batteries to feel that leaving 10% is wasteful, I really should be using rechargeables in the first place.

Anyone know how much juice is left in a battery that was run through an LSH when it kicks down to moon mode?