Specific LE efficacy question?

CroMAGnet

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I'm trying to compare three different set-ups for an Aleph LE, all using a single LiON rechargable CR123.

Which one would have the longest runtime? (how long?)
Which one would have the most lumen output? (how many lumens?)

1) TWOK 1000mA
2) UX1K 750mA
3) WX1S 400mA

For reference at spec:
TWOK 62 - 87 Lumens -- 3.51 - 3.75 vf
UX1K 87 - 115 Lumens -- 3.51 - 3.75 vf
WX1S 147 - 192 Lumens -- 5.91 - 6.39 vf

Also a link to an efficacy chart by Don chart post

Thanks for reading :)
 

chimo

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Here's a (very rough) swag asuming midpoint range Vf and brightness for each LED:

TWOK @ 1000mA.
Vf will likely be about 0.2V higher at 1000mA, say 3.83V. Power to LED: 3.83W
Output (@ 1.43xrated current, say 1.2xrated output): ~89 Lumens
Emitter Lumens/Watt: 23.2


UX1K @ 750mA.
Vf close to spec'd figure, say 3.65V. Power to LED: 2.74W
Output (@1.07xrated current, say 1.07xrated output): ~108 Lumens
Emitter Lumens/Watt: 39.4


WX1S @ 400mA.
Vf likely to drop about 0.3V from spec figure, say 5.85V. Power to LED: 2.34W
Output (@0.57xrated current, say 0.6xrated output): ~102 Lumens
Emitter Lumens/Watt: 43.6


You will also have to include the driver efficiency in your decision. The TW0K does not look like a good choice - too high power consumption. The LuxV will need a boost converter. The U-bin will need a buck/boost for stable regulation. The high Vf of the T-bin may let you get away with a boost converter (it may be direct driven for the first little while).

This was just a swag, there is a large range in each Vf and brightness bin, but the U-bin or the W-bin looks best.

Paul
 

CroMAGnet

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Thanksa lot chimo! It looks like the Ubin has about 21% more output than the Tbin. I might be able to get my hands on a Ubin with J or H vf for extended runtime.

Here's the set-up I'm after.

UW0J or H
NG750 LE
Single Protected 17630 LiON 1600mA
10ohm or 7.5ohm 2-stage
A19 Reflector

Is there a better way to drive a Ubin with those vf ratings?

Does anyone have any idea of runtime using this setup?

Thanks again :)
 

chimo

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CroMAGnet, with a UW0J and a NG750 you will be direct-driving the emitter for a while until the Li-ion voltage drops below the Vf of the emitter at 750mA.

In this will significantly over-drive the emitter for that period. You would be better off with a Wiz2 for that configuration or stay with a higher Vf U-bin.

Paul
 

CroMAGnet

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chimo said:
CroMAGnet, with a UW0J and a NG750 you will be direct-driving the emitter for a while until the Li-ion voltage drops below the Vf of the emitter at 750mA.

In this will significantly over-drive the emitter for that period. You would be better off with a Wiz2 for that configuration or stay with a higher Vf U-bin.

Paul
Ok, I'm catching on. Thanks a lot for the very helpful info. :)

I see there is a Wiz2 937mA, that is tempting.

But staying with the UW0J Wiz2 R1-0.12 R2-0.27 configuration would be the most efficient and highest output setup then? Can it be made better with the UW0H?

What type of runtime would I get with a single 17670 1600mAh protected LiON battery?
 
Last edited:

wasBlinded

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I don't think you will find a UWOH emitter right now. I've never heard of them being available, and if they were I would scarf up a few myself. Its more likely that the U flux bin emitters will be K voltage bins, though I have seen U??J emitters.

In terms of efficiency, i.e. lumens/watt, a nice TWOH will be very close to a UWOK.
 
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