LS - (Luxeon Star LED) on 2 AA Lithium battery test

[Silviron]

OK- The requested test has begun--

I cobbled together a LS LED (with optics) to 2 AA Energizer L91 batteries with 2010 expiration dates. Each battery when fresh measured 1.795V for a total of 3.59V.

I wired a switch in line that allows me to switch between "direct drive" and through a 1 ohm 1/2 watt resistor, with the expectation of needing a slight voltage drop to protect the LED from the initial higher voltage from the fresh batteries... in retrospect, I don't think that was necessary, because even on "direct drive" the module is staying pretty cool- (I don't want to dig out my thermocouple, so I'm just going to estimate it at right around 95 - 105 degrees FARENHEIT) NO heat sink is being used, although room air of about 78F is freely circulating.

With "Direct Drive" from the fresh batteries I get 100 LUX @ 1 meter - 3.08V @ 200mA at the module.

Through the 1 ohm resistor I get 75 LUX at a meter with 2.95V @ 100mA at the module.

(I'm not going to bother with the through the resistor measurements any more since it is unnecessary)

After 30 minutes, the no load voltage is 3.08V, with 2.94V @ 140 mA at the module. with 92 LUX at 1 meter.

At 1 hour, 82 LUX @ 1 meter, 2.94V @ 132mA at module. (3.05V no load at batteries)

 

[Brock]

Ok, so how does it compare to other LED lights with fresh lithium's? I would guess it would be close to the Eternallight? Did you try running it straight of 2 new Duracell's? I would guess lithium's would be better since they would hold their voltage longer.

 

[Silviron]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Brock:
Ok, so how does it compare to other LED lights with fresh lithium's? I would guess it would be close to the Eternallight? Did you try running it straight of 2 new Duracell's? I would guess lithium's would be better since they would hold their voltage longer.<HR></BLOCKQUOTE>

Beats me- The only LED lights I have here that I didn't make myself are the 4AA Dorcy and the Brinkman, and neither one of those would be any sort of decent comparison.

I haven't done a test on Duracells; may sometime, but not now.

Have done a test on Rayovac rechargable 1.5 V alkaline cells (both AAs and C cells) - some of that info is posted on the main "Whats up with Luxeon" thread, and some on my 3D LS conversion thread. I'll catch up on those stats later, but the most significant results are there now ....

 

[Coherence]

Thanks a lot Silviron for doing this - is there any way that you can measure a "standard" flashlight with your light meter and post the result (in LUX)?

For instance:
2 AA minimag
the Brinkman led light


<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR> I would guess it would be close to the Eternallight<HR></BLOCKQUOTE>

I have the Eternalight X-Ray and think the LS on 2 AA lithiums (fresh) is brighter with a better beam, and better color. Don't know what will happen yet as the batteries die, but thanks to Silviron we can all just wait and see...


<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>After 30 minutes, the no load voltage is 3.08V, with 2.94V @ 140 mA at the module<HR></BLOCKQUOTE>

Okay, I'm just making up a comparison.
Since the LS is about as efficient as the Nichia's, this would correspond to the brightness of about the Trek 7.

 

[Silviron]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Coherence:
...is there any way that you can measure a "standard" flashlight with your light meter and post the result (in LUX)?

For instance:
2 AA minimag
the Brinkman led light....<HR></BLOCKQUOTE>

I don't have the Brinkman handy (maybe can measure that tomorrow if someone reminds me...) but I have a brand new 2 AAA Mini-Mag right here with fresh batteries, and I get 140 LUX at 1 meter with the most tightly focused beam at that distance I can get...

HOWEVER: By eye, to me the light output from the LS at 8 hours looks about the same as the MiniMag with fresh alkaline batts....

Here is a photo to illustrate- The Mini-Mag is focused to provide the largest circleof light at that distance without having that gaping dark "hole" in the center.

_____________________________________________

After 8 hours the LS is putting out 69 LUX @ 1 meter, 2.89V @ 90mA at the module, (2.98 V no load)

 

[Mr Ted Bear]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>
HOWEVER: By eye, to me the light output from the LS at 8 hours looks about the same as the MiniMag with fresh alkaline batts....
<HR></BLOCKQUOTE>


I am glad to read that others perceive a less bright light (lux meter meassurement) as being on par with a light with higher measurements. The fact that the Minimag is tightly focused and the light has a different color temperature has everything to do with how the human eye/mind perceives light intensity.

In a related comparison, even though the Streamlight SL 35 is "brighter" than the Underwater Kinetics Light Cannon, it seems that I can see just as much with the Light Cannon.

Silviron, are you using the LX 101 Lux meter? One thing I noticed with mine is that by rotating either the source or the sensor by 90 degrees, the peak measurement varies.

Later I will measure the few leds lights I have and will post those findings, just as a reference for others

 

[Badbeams3]

I want to take a moment and thank you for running all the tests you have been doing...the LS looks like a real winner. Do you have a amber LS to run test on when these are complete?

Ken

 

[vcal]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by badbeam:
Do you have a amber LS to run test on when these are complete?

Ken<HR></BLOCKQUOTE>

Ditto on that amber one.
2 My eyes anyway, compared to white, details are much more discernable with the amber.
-Will there be a "high-dome" version??

 

[Silviron]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by badbeam:
I want to take a moment and thank you for running all the tests you have been doing...the LS looks like a real winner. Do you have a amber LS to run test on when these are complete?

Ken<HR></BLOCKQUOTE>

You are welcome-

Don't have an amber yet, but plan to get one soon as Gransee gets his shipment (and a green one too)
_________________________________________

36 LUX at 22 hours- will measure volts/mA next time

 

[Gransee]

I posted this in the other thread.. We now have ambers in stock.

Peter Gransee

 

[Silviron]

Thanks Peter- I'll put an order in right after this (Darn, I just got that credit card paid off

)

27 hours:= 26 LUX @ 1 Meter. 2.79V @ 30mA at module (2.83V no load)

 

[Silviron]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Pooh:

Silviron, are you using the LX 101 Lux meter? One thing I noticed with mine is that by rotating either the source or the sensor by 90 degrees, the peak measurement varies.<HR></BLOCKQUOTE>

Yes, that is the meter I am using... Concerning the rotation...Someone- (you?) brought that to our attention on an earlier thread, and I have been using that factor to obtain peak readings since then. I rotate the light and "aim" it around until I get the highest meter reading I can; then, I record the highest reading that stays stable for at least 5 seconds.
_____________------------___________--------

At 18 hours the LS-2AA Lithium is 2.85V @ 50mA at module, (2.89V no load) with 46 LUX at 1 meter.

(The earlier test on the Rayovac AA rechargable alkalines that impresssed me so much was at about 9 LUX at this point, so the lithiums are SIGNIFICANTLY better so far..(But we expected that didn't we??

)
{I must admit that I didn't expect it to be THIS much better though

}

 

[Silviron]

40 1/2 hours on the 2 AA lithium - LS now.

7 LUX at 1 meter.
2.71V @ 8mA at module.
2.71V on batteries with no load.

If someone can explain why I'm getting the same voltage under load and no load right now, I'd appreciate it. On all my other LS -battery tests I have always had at MINIMUM .01V more on the no load than on the load, even with the circuits without a resistor in them.

Even the LS on the 2 Rayovac rechargable alkaline AAs has .01V more on the no load:
After 397 hours of continuous operation THAT setup has 2.50V @ .33mA at the module, 2.51V no load. Enough light output to read by from about 10 inches (8 LUX with the LED right on the meter sensor)

 

[Silviron]

At 56 1/2 hours the 2AA lithium - LS test has 2.60V @ 1.7mA (no load voltage also 2.60V) -- 2 LUX @ 1 meter

I was too busy to measure things, but I noticed a rather sudden drop off of light at about 48-50 hours, then it went back to a slower, steadier decline. I guess that is kind of typical of Lithiums.

 

[Silviron]

80 hours continuous-
2.65V A .513mA on the new multi-meter.... ( I trust the readings on this new meter a LOT more than on my older meters, {but more on that on another post}..) No load voltage is the same: 2.56V.

On the light meter, I get a measurement of 1 LUX at 1 meter, 2 LUX @ 2ft.

 

[**DONOTDELETE**]

Silveron
____________________________________
If someone can explain why I'm getting the same voltage under load and no load right now, I'd appreciate it. On all my other LS -battery tests I have always had at MINIMUM .01V more on the no load than on the load, even with the circuits without a resistor in them.
______________________________________

cause 8ma isnt enough power to cause a drop within the meters capacity ?

cause you didnt wait long enough after the load was removed ?

cause with such a small drain the voltage drop is slower and more consistant with its actual LIFE.

got a Question for you
your tests are taking batteries down to the end of thier existance.
When we quit using Alkaline rechargables it was because they would not recharge well when taken to 0v.
the alkiline rechargables were a good idea as all alkalines are rechargable if they would SEAL them , which is what is the difference here in these.
but our use of them would take then 90% down, and they onley worked well (charged/recharged) when used to about 50%
to me they acted like a lead acid battery a few really deep cycles and they were not worth putting in anything.

how are you doing with the alkiline rechargables , and which brand are they and what TYPE of charge do they get, is it a 3hr type of charge ?

i suppose this belongs in the other forum, The one i dont go to

---------------------

 

[Silviron]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Video Guy:
how are you doing with the alkiline rechargables , and which brand are they and what TYPE of charge do they get, is it a 3hr type of charge ?<HR></BLOCKQUOTE>

The only testing I have done on the Rayovac rechargable alkalines so far is the initial test on 2 AAs- which after 500 hours of continuous operation are still running the LS. It is about 1 lux at 1 ft... still putting out enough light from 8 inches or so to read by. I would have quit this particular test long ago, but I am curious as to when it will quit completely.

I will try the 3 D- LS conversion on Rayovac D cells rechgargable alkalines soon.

__________------------______________---------___________-----------

As far as the LS 2 AA lithium test- I am going to give that up now...

After 150 hours The LUX output is 1 at 2 ft and 3 LUX @ 1 ft. 2.50V @ .31mA

Here are the interim measurements between now and the last time I posted info on this:

92 hours 2.55V@. 47mA 1 Lux @ 1 meter, 2 LUX at 2 ft.

118 hours 2.52V @ .34mA - 1 LUX @ 2 ft, 4 LUX @ ift.

140 hours 1 lux @ 1 Meter & 2 ft. 4 LUX at 1 ft.