LF3XT Runtime

h2oflyer

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My 1st CR123 got drained playing/programming/checking head temp. on high/ceiling bounce tests and generally playing around.

Drained another one by forgetting to turn off before stuffing in my pocket.
Was using momentary and must have quick clicked and didn't notice it was on while putting it away.

Have reprogrammed my FUI high to 66% - very little visual difference between 66% % 100%. High is there if I need it. Also dropped momentary.
Been monitering 3rd battery with voltage check - got about 20min. on it and reading 2.8 @ 50 % brightness. Run time looks better.

I'm a bit reluctant to run a continuous high run time test due to possible temp. considerations.
 

Splunk_Au

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Well, if you guys read the other thread on the LF3XT you can see that what he wrote is based on loose-ended assumptions on his part.

Simply looking at the post time/date and the entire thread itself shows what I mean, in comparison to what BabyDoc mentioned.

Btw, check out his post in this thread regarding his take on limited editions flashlights. Totally not based on any fact of actual limited edition flashlight. Thanks for that one liner Lite_me, I never get tired of those.
 

BabyDoc

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Babydoc, where are you getting this info? Do you know how to read?
In that thread on light-reviews.com forum it was clearly stated it was a flawed reflector which was why the review was held off until a proper one was provided. The review published was of the corrected reflector retail version of the LF3XT and latest driver.

And where are you getting this info on bad runtime with different driver? It was simply a decision by LiteFlux to revise the driver in the updated version to boost overall brightness. Man you're ignorant... people can really get alot of wrong info reading your replies to querries.

You don't need to be so rude. I think other people should read the entire light-review forum discussion and judge for themselves, particularly people who actually own a LF3XT. The pictures of the reflector are just like mine and everyone else. Although there was a suspicion of a problem with the reflector, there wasn't. The driver was changed and his brightness was corrected. The reflector was NEVER the problem, although at first that was suspected.

BTW, you need to be aware, if the moderator doesn't bring it to your attention first, there are rules on this forum regarding trolling.
 
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Chewy

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Baby Doc is one of the good guys. Always civil and always informative.
 

Sir Lightalot

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According to what i read in the light-reviews forum, the reflector did indeed have a bad ano coating so it had to be exchanged. A new driver was also introduced that made it a bit brighter overall as well.
 

DM51

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Splunk_Au.... it is a well-established convention on CPF that you may attack the post, but not the poster. If you have arguments with BabyDoc's post, then you may by all means state them; however what you may NOT do is descend to outright rudeness and insults as you have done above. I am formally warning you that it will not be tolerated here.

Please edit your post to remove the offending passages.
 

baterija

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Netkidz posted runtime graphs here. While there can be quite a bit of runtime variability introduced by battery variance and especially Vf variance (remember Cree doesn't bin for Vf) we now have 2 data points in the low 30's. I never got the feeling from the couple of 5XT graphs available that Liteflux was excelling at efficiency.

Since a number of us so excited about the 3XT have the 5XT already it's useful to remember that you can't compare the percentage ranking of the 5XT on Nimh to the 3XT percentage rating. 100% on Nimh in the 5XT is 500ma. 100% on the 3XT is 700ma. For the same drive current as the 5XT on 100% you're looking at 71% on the 3XT. My highest programmed level on the 5XT of 85% (that is barely discernible from 100%) is equivalent ton60% on the 3XT. On a primary cell, guessing from Netkidz 50% graph, I'm probably over 2 hours runtime for about the same light as my programmed high mode on my 5XT. Not too shabby and I always have higher available if I really need it. :thumbsup:
 

h2oflyer

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When I program my LF3XT to different brightness % , am I changing drive current or calculated lumen output ?

If using 1500 Duracell primary @ 100%(700ma) ;30 some min. would be reasonable if current draw/runtime is linear?

I know graphs show runtime to 50% , but it's downhill after that.

If I really am programming current draw ; can't I just extrapolate to estimate run time ?
 

Flying Turtle

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I don't think things are quite linear at the end of the battery's life, but maybe close enough for rough estimates. Most runtime graphs for regulated lights have a steep drop at the end. Once you hit 50% there's not usually much time left unless the light goes into direct drive. I suppose you could measure the slope at 50% and extrapolate an end point assuming there's not much of a tail off. Maybe one of our experts can help.

Geoff
 

h2oflyer

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Geoff

I forgot about the difference between regulated and direct drive.

I am running a run time test @ 100% on for 2min. every 1/2 hour and checking battery voltage at end of 2min. Might be late on next sequence as I have to fire up the snow blower.

I guess if I had time over the Holidays I could repeat @ 50% and compare.

Will report when done.

Walter
 

Flying Turtle

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Thanks for doing the testing, Walter. That should give us a "real world" idea of how our lights perform.

Have fun with your snow blower. Growing up in Pittsburgh I always wanted my Dad to get one, but he'd just chuckle and hand me the shovel.

Geoff
 

dig-it

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Thanks for doing the testing, Walter. That should give us a "real world" idea of how our lights perform.

Have fun with your snow blower. Growing up in Pittsburgh I always wanted my Dad to get one, but he'd just chuckle and hand me the shovel.

Geoff
Thanks goodness you`re in Apex now where even a shovel is overkill.
 

baterija

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When I program my LF3XT to different brightness % , am I changing drive current or calculated lumen output ?

If using 1500 Duracell primary @ 100%(700ma) ;30 some min. would be reasonable if current draw/runtime is linear?

I know graphs show runtime to 50% , but it's downhill after that.

If I really am programming current draw ; can't I just extrapolate to estimate run time ?

First let me take a step back and say I don't know of any proof or statements from Liteflux that percentages are based on current draw. There was something in one of the 5XT threads a while back that made the case and it seemed to make sense. It made more sense because LF isn't claiming an output but does mention max drive current. There's no proof though. I think at this point it's better to think of that as an unproven assumption that LF calculates percentage based on current rather than output.

Even if that assumption is correct, and working around regulated vs direct drive, I would not expect runtime vs current to be linear for a couple reasons:
- Vf varies with current supplied. Doubling current requires more than double the power since Vf goes up as well.
- The watt hours provided by the battery is not constant. As the current drawn on the battery goes up the power capacity (watt-hours) decreases.
- Power consumed by resistance is related to the square of current. So when current doubles the power loss increases 4 times.
- At the lower end PWM has an effect and we know they are using PWM to get their low. .2% probably isn't 1.4ma. It's pulses of a higher current (with effects mentioned above for higher current) with periods of no current that average around 1.4ma over time.

Here's a quick and dirty graph of the 3 runtimes Netkidz published showing runtime versus percentage. I only used the RCR and IMR RCR runtimes since that avoids the non regulated tail issues. It's only 3 data points so it the curve may be wildly inaccurate, but it at least provides an illustration of what may be going on and why it may be hard to extrapolate from current to runtime.

netkidzlf3xtruntimesrp4.jpg
 

h2oflyer

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Here's my run time test.

I wanted to simulate real conditions and I didn't want to thermally stress my emmiter with a constant on. Used a new 1500ma Duracell CR123 and ran test by switching light on for 2 min. every 30 - 40 min. Checked battery voltage twice at end of 2 min. on cycle. Output was at 100% and monitered this level by comparing brightness to Nitecore Extreme reduced to comparable brightness level.

I started at 09:00 reading 3.1 v @50%

09:10 2min.@ 100% 2.5 v
09:40 " " 2.5 v
10:20 " " 2.5 v
11.20 " " 2.4/2.5
11:40 " " 2.4/2.5
12:10 " " 2.4
12:40 " " 2.4
13:10 " " 2.3
14:30 " " 2.4/2.3
14:50 " " 2.3/2.4
15:10 " " 2.3
16:00 " " 2.3
16:20 " " 2.3
16:40 " " 2.3/2.2
17:10 " " 2.2/2.3
17.30 " " 2.2/2.3
17:50 " " 2.1/2.2
18:10 " " 2.1
18:40 " " 2.1
19:00 " " 2.1
19:20 " " 0.9/2.5 ****

At this point output was reduced to 50% user default.
I ran the test in CUI so that I could allways confirm 100%
and compare to 50% user default.

42 min. on 100% high -- not shabby at all !

Walter
 

madi05

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so i wonder what a rechargeable would do in this same real time setting? hmmm

thanks for the update , im going to bite, lol

madi05
 

Flying Turtle

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Thanks, Walter, for giving your time, attention, and a good battery all for the cause. I agree. Not too shabby. I'd say our new light is still looking good.

Geoff
 

h2oflyer

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Decided to continue run time test from post #36using same cell.

Ran test at 50% in FUI so that I could compare brightness output to my 15% & 66% settings. Also set up the Extreme @ comparable brightness as a reference standard.

07:30 - 50% - 2min. on - 2.5 v
08:00 - " - " 2.5/2.4
08:20 - " - " - 2.3
08:30 - " - " - 2.2
08:40 - " - " - 2.0/2.1
09:30 - " - " - 1.8/1.9
12:00 - " - " - 1.7
12:20 - " - " - 1.5
12:30 - " - " -0.6 **** ended test - brightness started dropping rapidly.


42 min. on 100% high and 16 min. on 50% from a primary cell is good for me. I'm confident that at 80% (100 L) output I could get 80-90 min. out of a 1500 ma primary.

I see selfbuilt has just ordered a LF3XT. - Now we'll see some REAL runtime tests.

Walter
 
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