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burntime accuracy

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burntime accuracy

Postby Guest on Sat Sep 19, 2009 12:24 pm

How accurate are the flashlight Manufacturer's ratings?

For example the Pelican M6 claims to have a 40 hour burntime at 41 Lumens and the surefire G2 LED has a rating for 12 hour burntime at 80 Lumens. How much of the stated time is accurate usable light? What is the light decrease rate as the battery dies. Is there some sort of light drop off. Like, 100% claimed Lumens or brightness for 2 hours than a drop of to 50% lighting for a few more hours then a 10% of the light for the remaining time.

Re: burntime accuracy

Postby Ryan_W on Mon Sep 21, 2009 1:30 pm


This completely depends on the light itself. The Surefire LED models are highly padded with their 11-12 hour figure. The Surefire G2 LED (and similar Surefire LED lights) runs at full power for about 1 1/2 hours and then drops off. The last 7 or 8 hours are at non-tactical lower light levels.

Some lights like the Streamlight Scorpion LED and Streamlight Strion LED are voltage regulated. These are regulated to give you the maximum amount of brightness for the maximum amount of time. This may reduce your overall run time, but you have much greater output for that full life. The downside to this is the lack of warning for the end of the battery. I use the Streamlight Strion LED. This unit starts out at 160 lumens. After 2 hours, it has dropped down to about 140 lumens. About 5 minutes later, the battery is dead and it's time to charge it. The Scorpion LED is similar, but is not rechargeable and is not as bright.
Best regards,

Ryan W.


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