Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels!...

First, before I say any word, Let me state, No Intentions to Trash/Disrespect anyone/anybody.

Just wondering What will be effect of Overdrive that VIP,LH,LC are having.

VIP --> 1000mA --> TWOJ ??
LH --> 1400mA --> TWOH ??
LC --> 1740mA --> UWOH ??

Dont know for sure, but How long does LED Last in these lights?

Just came to know after lumenaria posted the informaiton about the LuxReadings after a few hours of usage...

If, I want to have let's say 1000 Hrs of Life on LED(30% permicible drop in Lumens), how much should i permit through LED ?....

Currently I am overdriving Lux3 TWOK @ 800 mA - 900 mA Range with a Li-Ion...

Can any one please tell.

i thought this, but just based on conjecture.
if you can dissapate the heat well, on a LUXIII you can go to 150% and get 125% type light, anything over that is just a waste and when you get to 1500ma and over with a loose to the air star, it already starts to overheat and lower in brightness (for the current going in).

i get this from just dangling them about and cranking on them with voltage regulation and reading the amperage headed to the thing.
if it LOOKS brighter /ubbthreads/images/graemlins/smile.gif and its not gone up terrible on the meter , well then it IS, if it can stay that way airborn, it might be able to do that encased with proper heat removal.

so from my TOTALLY LOOSE estimates i say take it to 150% and get the bit brighter. take it OVER that, and hopefully you would do this for a shorter period of time.
IF by the time the thing is blazing hot, on a DD setup, the batteries have weakened, then its still ok to me.

when you say almost 2A, i say ok, but for how long do the batteries hold this for?

a light is kewl if it bursts up a bit when you first turn it on, and great when it slowly dies down when the battery is running out. as long as that is surviving the heat issue , then its FUN. if its overheating then it will soon be dimmer than anything you got :-(

that is all i know, i HAVE taken them to a full 2A (or is that a FOOL 2A) survived, and is as bright as the others still, but it was CERTANNLY overheating on the road to death, if i did that for a long time. Usually in Pannic , when i see it get that high, i cool it out within a few seconds.

just depends.
want me to FRY one , because that is rather hard to do.

that is all i know, they are hardy, when you go over spec it goes from a more Linear output to 50% that. so i would think from the eyes if you 200% spec, you get only 150% output.
i would prefer that it not go over 150% for any length of time.

at SOME point in over drive or overheat, you will get VERY POOR output for the current you put in, and mabey permanentally ruin it.
but even if you run SPEC and totally overheat it the same thing could occur.
so overdrive, if you can pull heat better. that is why on all my overdrives i make sure that the heat moves out very well.

sombody could probably do a chart, and i would suspect that it would go almost linerally up to SPEC, then start going down in Lumens per watt, then take a DIVE , when it baked into oblivion. what difference is that from a 5MM.

and if i was not Rambling enough

stating specific models and some arbitrary rate that somebody read on it at ONE MOMENT, doent tell ME anything about the lights TOTAL properties for surviving an overdrive, and it could change 100% or more, if your HAND was not on it leeching the heat into the human.
it can also change totally if this is only the burst rate, or if the light is only ever used for bursting.

also look at how that simple spring adds in major current changing resistance, also LEADS of the meter (wont mention WHOS have Lots and lots of resistance, totally changing all the metered results.

if you want to know the average, not burst rate the led is REALLY being hit with, when its in a light and fully assembled, then check its RUNTIME with its capacity.
anything else can be subject to variations in the testing methods.

If it doesnt work, we will certannly HEAR the complaints right here /ubbthreads/images/graemlins/smile.gif

i have a few manufactured pieces of luxeon junk that i am playing with here now, and they did NOTHING for a heat sink, they underdrive, but its totally encased, with no good dissipation. it is as likely to die with the method they used, as the method i am about to torture them with /ubbthreads/images/graemlins/grin.gif

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

Hi, I am Quoting....luminaria .. from This Thread

[ QUOTE ]
luminaria said:
Let me insist /ubbthreads/images/graemlins/dedhorse.gif that increasing the current above certain levels gets you very little (and soon nothing) at a too high cost.

I will show it with a real life example using data of some measurements I did a few weeks ago in a DD QIII:

current: 820ma -> lux: 1350 (with resistored spring)
current: 1440ma -> lux: 1620 (unresistored)

A 75% increase in current translates to only a 20% increase in luminosity /ubbthreads/images/graemlins/ooo.gif

Advantages: you get a 20% increase in luminosity. Wow! /ubbthreads/images/graemlins/buttrock.gif Nope! Many people do not grab the fact that due to the logarithmic nature of your visual perception, you will practically not notice the difference . When I received my luxmeter I did some tests and I had difficulties to clearly notice a 50% increase in luminosity.

Disadvantages: your luxeon WILL notice the corresponding 75% increase in current and the 5W level overdrive. Not even your copper heatsinks will be able to properly disipate such heat. Soon you luminosity increase will turn luminosity decrease (but a good point is that probably you will not notice until it gets down to 50% /ubbthreads/images/graemlins/grin.gif) Vf shift will do things worst in the next 50 hours...

Pluses: your runtime will be reduced to 57% of your original one.

In resume, you get a short-lived light that seems no brighter than before, but runs half the time and gets a lot hotter. /ubbthreads/images/graemlins/thumbsdown.gif

I am afraid that these problems are going on, mostly unnoticed in a lot of DD lights, like the Raw, the Lion family, the DD Jil when overdriven with R123s,...

I bought a Lionheart with few hours of use according to his previous owner and in mint state. But it only gave 1250 lux for a TWOJ, which it is a very low reading with a 27mm reflector. I exchanged the star with a new one, same bin, and it went up to 2400 lux.

If the old luxeon were a worst case T-bin and the new one a best case T-bin, the Luxeon lottery would account for a 30% increase in luminosity. But I got a 90% increase. So I think the only explanation is that the old luxeon was severely degraded, and that after only a few hours of use...

I think that the clever thing to do is not to copper/gold plate the spring but the opposite, to increase resistance a little.

[/ QUOTE ]

My Aim is to make my QIII Last atleast 1000 Hours ... without much noticable degradation...

The QIII Heat Sink Idea was this very basis for doing a DD... in a protected manner...

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

i donno , i own neither, and i have read his testing.
everything he says has validity.
a TINY light like some of those, will heat up very fast if not held in hand. i assume people paying 2-300$ for them use some sort of care when they use them??

does your heat sink get sinked to the case that it is going into well? to transfer the heat?
are you running pounding overdrive?

the specs you said ""Currently I am overdriving Lux3 TWOK @ 800 mA - 900 mA Range with a Li-Ion...""
sound like the ticket, AS LONG AS, the heat is leaving the emitter.

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

Heat Sinking does a much much much better job... as compared with Orignal Nuwai QIII's Ring.. i have used the light for long periods.. and it does manage to get hot... but not 'that' hot that you cant hold it... just luke warm hot.... and it settles there... may be around 36 - 42 degree celcius

It's not a Emitter but the Star...

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

i think you WANT the body of the light to get hot, otherwize the heat is staying in there.
having a heat sink is one thing, having the conduction send the heat OUT , where it can get out, is the only way its going to work right in a containment like these flashlights.

the primo smalls made by the geniouses here usually have excelent conduction of the star or emitter to the body , and out.

the stuff i have seen at wally mart and target, cant do that very well through PLASTIC parts /ubbthreads/images/graemlins/smile.gif

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

It Does get hot /ubbthreads/images/graemlins/smile.gif and at the same time, It stabalizes at a lower "hot" temprature ....

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

Hello ViReN,

Just to throw some more numbers out...

I have two natural HA LionHearts. One I use for work and it has over 150 hours of run time on it, and a lot of that time has been on high. It measures 2900 lux at one meter. The other light I use around the house and carry it during "dress" outings and to show off to my friends. I have around 8 hours on it and it measures 2860 lux at one meter.

My black CPF special edition LionHeart has a different LED in it and has under 3 hours of use. It measures 2330 lux at one meter.

I am not sure if this means anything due to the differences in LED's and reflectors, but after over 150 hours of use, my work LionHeart is still going strong.

Tom

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

Viren,
Lumen maintenance is a real consideration and one faced by anyone designing a LED based light. Lumileds as well as all other LED manufacturers provide information regarding current levels and operating temperatures and often the expected life or lumen maintenance of the LED as a function of both temperature and current.

Many of the DD lights operate well beyond the parameters set forth and considered by the LED manufacturers. For a disposable $3 keychain light at the grocery check out counter, this is likely a non issue as many will not bother with battery replacement and just toss the LED light after the batteries expire. /ubbthreads/images/graemlins/icon3.gif

DD has the advantage of no power loss due to a regulation circuit. It has the disadvantage in that there is no regulation and the LED's are a current controlled device by design and intent of manufacturer; plain and simple. A DD set up where the LED is driven below spec enjoys both the increased efficiency or efficacy inherent in white LED's as well as the benefit of no power loss in a regulation circuit.

As to the expected or anticipated lumen maintenance of the Luxeons driven at current levels you have cited in your initial post, I don't know if these can be extrapolated from beyond the information provided by Lumileds or if it will depend on empirical investigation. /ubbthreads/images/graemlins/icon3.gif

The ease of star replacement in some of these lights might be a saving grace if one actually wants to continue to have a bright light and the strategy of disposable Luxeon stars is embraced. Perhaps the tailcap cold be expanded to host a spare star like some manufacturers do with spare incan lamps! /ubbthreads/images/graemlins/grinser2.gif

One company who is known for bright lights and has a tag line "Smaller, Better, Brighter" currently has a single cell light that now offers a two level, constant current drive to a Luxeon III. The high level of current is slightly in excess of 400 mA as I understand it. Now this company is known for their high end products, quality and performance in service. Why do you suppose there is such a disparity between what they are offering and what can be had here on CPF? /ubbthreads/images/graemlins/thinking.gif I believe it is their intent to produce and provide flashlights which will have a long duty life and be essentially as bright way down the road as they are out of the box. The beauty to LED's, IMHO, is in their potential of providing a lifetime of lumen maintenance well beyond the expected use of the light with no need for replacement and in fact the typical design is such that the LED is integral and not intended for replacement, ever!

Ironically, there are some CPFer's who refuse to buy a L4 for $140 because the LED may only have a half life of one or two thousand hours. Others are willing to pay twice that price for a light whose LED may have a half life measured in hours. /ubbthreads/images/graemlins/icon3.gif Perhaps it's just different strokes for different folks or perhaps it is something else. I would guess that some of these lights will never see 10 hours of run time so the point is moot.

EDIT: I have a LH that I put a "L" Vf bin LED in and it runs below 1000 mA for the full life of the Li-Ion's output. This light should last well beyond my time! It is efficient and quite nice in service! I also have a Ti LC that has not been built out with a LED yet and given the Ti thermal issues, I intend to use a very low Vf Luxeon and CR123 for a low current DD system.

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

i dont know but i bet the led will last longer then most people will ever use the light.im no expert but ive alwasy overdriven my cpus in my computers i just make sure there cooled good.only reason i dont overclcok this pc is i want to lower my electric bill so im runing it at stock speed but im also runing it way undervoltage

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

Wow /ubbthreads/images/graemlins/smile.gif McGizmo...

Thanks for a Wonderful Explanation. I am one of the person.. who wants to use Bright... Long Lasting(Both LED & Runtime) and Efficient. Regulation... with Li-Ion Discharge curve wont be much of an issue ....

Also, It's surprising... to note that there are some lights that use LED and LED is lasting only for a couple of Hundred Hours.

The Intent of LED when it was invented (as a indicator light) was to have Loooonnnggggg Life .... and as days progressed by... LED's became more efficient... but what i dont understand is driving at a 'break-point' scenario to get brightness....

One can get More than that Brightness(as compared to LED).. if they use InCand's & Of Course a great Throw ... Xenon & Kripton's will make the light White too...

any ways....

so i think, with a Good Heat Sinking, Good Thermal Management, TWOK Driven @ 800 - 900 mA with a Li-Ion should give a best compromise of Brightness, LumenMaintanance, Runtime, LED Life time ... and for this you can use any host.. be it QIII or other good hosts...

And I feel that... for those who intend to run LuxIII LED's at 1.2 or 1.8 A Levels.. should seriously think of switching to HotWire. Brighter, Cheaper, Thrower. More over Cost of Replacement of the "light Source" will be much lesser too.

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

ill always take brightness over a long life light.every day.i like bright lights

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

As far as I know, the VIP driver is current-limited to < 1000mA on high. The boost circuit is more than just a voltage boost. georges might confirm.

The LH & LC use PWM to control LED brightness. On full power, they're straight DD, with the controller doing little more than closing the circuit between the LED and battery. On anything less than full power, the controller is closing and opening the circuit at high speed, with the length of the closure determining the brightness.

A PWM setup running at < 100% duty cycle does restrict current. If direct drive pushes 1500mA through the LED, then 50% PWM runs 750mA, 25% PWM runs 375mA, etc - averaged over time. The pulses are typically so short with PWM that 50% x 1000mA might as well be 500mA as far as the LED is concerned.

Direct Drive scenarios are highly dependent on matching the characteristics of the LED & power source. When fully charged, a lithium-ion cell has an open-circuit voltage of ~4.2V. On average, it's closer to 3.7V - 3.6V. The Vf of the LED is of critical importance. It's possible to safely direct-drive a LED if its Vf is high enough that it self-reculates current within the "nominal" voltage range of your power source... assuming the peak voltage doesn't last too long or the brief current surge doesn't kill the LED.

It's usually more reliable to control current than voltage, given the tendency of LED Vf's to drift as the parts are "burned in" and the wide range of voltages that most batteries put out.

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

raggie33, How much do you use light per day?

For me, use is like 30 - 45 minutes each day.. due to now regular power failures here. most of the time.. it's QIII that i use. so it's absolute essencial that my LED Lasts ....

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

First of all ViReN, no disrespect taken, by me at least! I would say that if your Luxeon (III, for example) is permanently, unremovably POTTED in place as in some light engines, requiring one to shell out $45-$60 to replace, then a safe alternative would be to drive it no higher than the factory recommended max for Lux IIIs (1000 mA), or even some still-bright-enough level below that. But if you can quickly and easily replace the Luxeon, and if absolute max brightness is your goal (as witnessed by the many lux meters in ownership around CPF), overdriving is indeed a viable way to go.

The fact is that lumen maintenance is a continually degrading issue even when a Luxeon is driven at lower levels. If your aim is to install a specific, long-term application that will reliably put out a specific lumen volume, then I would use a regulated system and drive it at the lowest possible current that still provides the necessary level of ouput. But if your aim is to play with lights, dazzle inlookers thereby converting non-Flashohlics to our swelling ranks, light up something across a street or down the block or up in the hills with the smallest EDC'able unit you can still pull out of your jeans coin pocket - and it is a light on which you can easily replace the Luxeon if and when it does visibly degrade - then hey, I say go for it.

As I have stated before, we're not building refrigerators or nuclear reactors here, it is the hobby and bleeding edge aspect about flashlights we enjoy, and we should keep things in perspective. Obviously many agree - look at all the Orb RAWs and Jil DDs and Lion lights out there. And we each have so many other types of lights - wouldn't be a real Flashoholic if you didn't and likely would not even be here - that all types are likely to, and should, be represented in our respective collections. Also if lumen maintenance is so critical, then it should not be confined just to LEDs - just look at how many USLs and Mag 85s and modified TigerLights, et al, are or will be enjoyed out there at this very moment.

Finally, differences in measured lux output can also be attributed to the Luxeon Lottery - and thus swapping out one Luxeon with only a few hours' use for a new one and getting a higher reading is not a necessarily a concrete indicator of lumen degradation. For examples of both these issues simply witness SilverFox's own real-world experiences, posted above.

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

proably about the same but i use em for play in this house. but in my old house the power went out all the time.i bet a overdriven lux 3 led will still last about 10000 hours.but this is just a guess.so if my guess is corect thats about 5000 days for you .now i could be wrong im no expert but non of my overdriven leds have dimed on me yet.

Re: Mr Bulk... VIP, LH, LC Luxeon OverDrive Levels

Wow again /ubbthreads/images/graemlins/smile.gif Thanks Mr Bulk for your kind reply.

So, Some Luxeon's can be "dud's" ... in deed Luxeon Lottery...

Raggie33 /ubbthreads/images/graemlins/smile.gif thanks again for your calculations...

now i should rest double assured that my only Luxeon Light is going to survive for days to come.....