UB3T and 17500 runtimes?

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Mar 7, 2007
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Has anyone done runtimes on the SureFire UB3T using 17500 cells?

Any estimates even?

I would be particularly interested to know how long it runs on the quasi-regulated max (~800 lm) level on 17500s compared with 3 x 123 (where selfbuilt's graphs suggest 35 min at 800 lm).
 

WarriorOfLight

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The AW17500 cells have 1100mAh capacity. I measured ~1.6-1.7A at high when I used my UB3T @ max. At 1.7A a 1100mAh cell will have ~38 minutes. I assume the runtime at maximum should be the same with two 17500 cells and 3x CR123.
 

badtziscool

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Strange. SF says runtime on High for the UB3T is 1.7hrs. That's 102 minutes. I know that their measurements is most likely using 3 SF cr123 batteries, but a typical SF cr123 has a capacity of around 1500mah, and even considering the source voltage is 9v vs 8.4 for the 17500s, it doesn't explain the extreme discrepancy in runtimes. Is SF padding the stats a little?
 

WarriorOfLight

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My estimation was the usage of the real 800 Lumens, not the time when the brightness is belos 50 Lumens, what SF uses.

With 3xCR123 the UB3T runs ~30 minutes on 800 Lumens. I think the two AW17500 cells will reach the same time. LiIons are better with higher currents. Therefore this guess. A current of ~1.7A for CR123 cells is really high for this cells. I would not drive CR123 cells harder.
 
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