Looking for Run-time Data on this basic flashlight...can anyone help?

Stevie

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So.....I own some nice lights from Fenix, Armytek, Zebralight.....some nice Flashaholic lights with which I am very pleased with. They each haver their own dedicated use for me.

But on Saturday I saw an LED Lenser P7.2 going being sold at "the right price"....that is to say it was being sold at a price which suits the low technology....and curiosity got the better of me and I bought it. From a Flashaholic's perspective, I do know that these lights don't receive a lot of love from the community due to the direct drive, non-regulated output and from what I have heard, generally poor runtimes.

However, purely to satisfy my own interest in anything with an LED, I spent a bit of time over the weekend looking for true runtime data / output curves, but despite the excellence of the CPF search function, (and after that using a different search engine), I couldn't find any runtime graphs.

I'm particularly interested in the output curves of Alkaline cells vs Nimh's. I will use Nimh's in mine (and yes, I have read up about being careful of heat / overdriving with Nimh's). I'll probably just use this thing on low output anyway for very basic general use.

Thanks guys, any links to those runtime curves much appreciated!
 
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stephenk

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There is runtime chart somewhere on this forum - have you tried the search function? From memory, the time/output curves closely mimic a typical NiMH discharge curve (initial drop, then slow decline, then drop). NiMH will maintain higher output for longer compared to Alkaline, and there are no heat issues with this light (you have to hold down the switch for turbo/boost mode).
 
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TCY

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I own a P7.2 and I stuff NiMH in it. In general LL's claimed runtime is reliable, it does have incredibly long runtime but only because of direct drive that gradually diminishes output.
 

Stevie

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@ stephenk - thanks, yes, I have tried the CPF search, but the runtime data posts on this light seem to be from about 10 years ago and the images of the curves are no longer there unfortunately.

@TCY
I own a P7.2 and I stuff NiMH in it. In general LL's claimed runtime is reliable, it does have incredibly long runtime but only because of direct drive that gradually diminishes output.

Problem with LL is that their stated run-times are down to 1 lumen, which is not very practical.... What do you use yours for? Indoor general tasks or perhaps outside walking the dog etc? It would be interesting to get your take on long term use. I am now thinking of using mine for car camping and as a basic "walk around the campsite" light. I wonder if I used it on low level, using Nimh's, would it last a one week touring trip whereby it is used for perhaps 15-20 minutes per evening. I say "last"....for me, that means still punching out a 50-75 metre beam on the low setting. What are your "useful runtime" experiences with it? Many thanks.
 

TCY

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@ stephenk - thanks, yes, I have tried the CPF search, but the runtime data posts on this light seem to be from about 10 years ago and the images of the curves are no longer there unfortunately.

@TCY


Problem with LL is that their stated run-times are down to 1 lumen, which is not very practical.... What do you use yours for? Indoor general tasks or perhaps outside walking the dog etc? It would be interesting to get your take on long term use. I am now thinking of using mine for car camping and as a basic "walk around the campsite" light. I wonder if I used it on low level, using Nimh's, would it last a one week touring trip whereby it is used for perhaps 15-20 minutes per evening. I say "last"....for me, that means still punching out a 50-75 metre beam on the low setting. What are your "useful runtime" experiences with it? Many thanks.

TBH mine has been collecting dust for ages, but I do remember the great runtime, albeit output drops. It'll be alright for outdoor in general but I'd carry an 18650 light. I didn't have a chance to do a runtime test but based on your scenario my wild guess is yes, the P7.2 would last that long. That said, I would still take a Fenix/Armytek/Zebra. Led Lenser makes good quality torches and offer great customer services, but unfortunately their technology is just behind.

Now that I got some sleep I feel like I misread the scenario you provided. If you are talking about 20 minutes * 7 days on high and still have some usable low, then no. Led Lenser has changed their runtime claim to 1 hour on turbo which is a lot more practical.
 
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Stevie

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@stephenk - many thanks for that. So 75 min is around 30% of the claimed runtime. This might be un-scientific thinking, but if I assumed the same type of 'discharge curve shape' for operation on low mode, I might expect around 15 hours before noticeable drop-off in mine. Actually, that's a crude estimate, you have to take into account that the light always comes on in high, so if you imagine switching it on you'd have to get it into low as fast as possible...doing this night after night with a few seconds of 'high' before reducing to 'low'.... perhaps a more conservative estimate would be 10-12 hours. We'll see...

Thanks all for your replies here, much appreciated. Steve
 
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