Come in and join me....

[The Propagator]

http://cgi.ebay.com/Clearly-LEDs-Aquarium-...1QQcmdZViewItem

 

u think u can grow anything with 12w-14w of light?

the max lumens efficiency on thos 5mm LEDs is 40-45lm

 

if it were more compact it would make a good light for a small refuge.

 

 

Hey I just post what I find.

Its your job to prove its worthyness

I know nothing about LED's

[evilc66]

I am pretty sure they are not using the K2, but rather the Rebels

 

 

PFO is using the older generation K2 in the current I4 Solaris fixture. The older fixtures are using the Luxeon I LEDs. Aqua Illumination is using a Seoul Semi LED (can't remember which one), but no-one currently is using the Rebel in a production fixture.

[coolwaters]

LEDs are just light emitters. but the white LEDs are filled with phosphors (to make them white...) and such they emit rays that well emit heat. thats why i feel them at 1 inch away. but after that its basically visible light.

 

im almost done with my project just need that dam epoxy....

 

you'll know when someone is using rebels...there like 50 times smaller...i know i had to solder 2 of them...

 

i just wished that they had the leads on top not on the bottom .2mm away from the thermal pad...

 

 

lol PFO is using Luxeon and AI is using Seoul and im using CREE and Edison.

the edision is like the biggest bang for the buck right now and CREE is the only Blue LED i can find....cheaply...

[SaltyJohn]

collwaters, which Edison LEDs are you using? The only one that somewhat interested me was the EdilineII 5W. I did not spend a second on the 50W/100W LEDs they put out though...

 

So, which one do you say is the biggest bang for my (well, your) buck?

 

Also, coolwaters what are you doing controller wise with your array?

[coolwaters]

well i havent thought about the controllers i was thinking about putting up switches but thats too much trouble.

 

so its just a off and on light for now.

 

for the white LEDs im using Edison Opto KLC8.

which i got over here

http://www.kaidomain.com/WEBUI/ProductDeta...spx?TranID=2308

 

but if i help someone build one for a 55g+ tank i'll get it here

http://www.volumerate.com/details.vr/sku.4282

 

btw the 50w+ leds are crap. efficiency is around 30-40 lumen per watt.

Cree says they made a 800 lumen LED that runs on 10watts but im pretty sure its just 3 LEDs put together...

[SaltyJohn]

Well, I did a little side-by-side on the three major LEDs out there (I left enough out of the research off the bat, like Edison, Refond, Citizen and Huey Jann LEDs).

 

The short version is as bellow:

 

Cree's XR-E Q5 (XREWHT-L1-0000-00D01)

If you are going to drive at 350mA (92,64 lm/W)

If you are going to drive at 1000mA (61.67 lm/W)

 

Luxeon Rebel (LXML-PWC1-0100)

If you are going to drive at 700mA (75.63 lm/W)

 

(Seoul Semiconductor's Z-Power P4 was the third LED if anyone is wondering)

 

Now, the biggest bang for the buck depends greatly on your source. I have found both of the two LEDs above anywhere in the neighborhood of $9.99 - $4.95 (plus shipping) and that is a big variation!

 

All in all, I think the XR-E at 350mA -keeping everything cooler and lasting longer- is the path I will take with my next project. Plus I can run more parallel arrays out of my 48V/5A switched PS (at 350mA per, 5 Amps can safely drive up to 10-11 arrays, with a few Amps left for 'breathing room').

 

EDIT: And as I was typing the above, I received email that the R bins (XR-E R2 instead of XR-E Q5) have been released and some retailers are already stocking them. That is a 100lm/W LED @ 350mA as Cree reports.

[evilc66]

Don't forget the Rebel @ 350mA. Thats 84 lm/W.

 

Not too shaby

[SaltyJohn]

...the Rebel at 350mA ranks in at 90,7 lm/W (100 lumens at 3,15V/350mA which is 1,1W)

 

I just mentioned the best of my test, at each current rating. Rebel is (was) a close second to Cree at 350mA indeed, but now with the new R2 Cree, the Rebel is falling way back in all three ratings I am assuming. More when I get the new specs for the R2 bin.

[evilc66]

I wouldn't call the Rebel "way behind" the R2 Cree. The R2 is impressive, but only 10lm in front of the others.

 

Cost per watt is now something to look at. The rebels come in at half of what the R2 will ship for initially. Thats a big savings when you are using 100.

 

I'm not trying to dispute that the R2 will be an awesome LED, or that the Rebel is the best thing going. I'm really trying to say that there are LEDs that are better suited for different applications.

 

For example, the R2 is not well suited for small tank applications where space and cost are going to be issues. The smaller size of the Rebel, and lower pricetag work well here. Any other LED is jsut too big to fit in the smaller area and give the desired light output.

 

For larger tank applications, the R2 will be better suited because of it's higher intensity and the space available is greater. The Rebels could be used here, but at greater cost overall to match the total light output.

 

Now, a lot of what I just said is more my opinion than fact, but based on what I have seen so far, this seems a logical outcome. I'm not trying to argue, just trying to talk about the pros and cons of the different setups.

[Gomer]

The rebel also has a MUCH wider cone angle then the cree. For something like a biocube retrofit, without optics, you would loose a LOT more light with the rebel then the cree.

 

Just another side of the "rebels are cheaper" coin

[evilc66]

True, but you can also get LEDs alot closer than any other type of light source, and minimize the light lost even without optics. Most of your light is in the first 35 degrees off center anyway.

 

The Cree XR-E LEDs at 30 degrees only keep 80% of it's light intensity, where the Rebel sits at 85%. At 45 degrees the XR-E drops to less than 50% light intensity, where the Rebel is at a pretty healthy 70%. Just because an LED has a tighter viewing angle, doesn't make it better.

 

The Rebel outperforms the XR-E in intensity percentage at all angles which would actually make it better when used without optics in comparison to an XR-E without optics. There was a thread on this forum that showed that any light under about 60 degrees off center would penetrate the surface. (I'll have to find it) That still make the Rebel usable without optics.

 

The Rebel then would improve even more with optics because the reflector (which works better with a wider viewing angle LED) can now do its job better and focus even more light than the XR-E could with optics.

 

Don't knock the Rebel just yet.

[Gomer]

no, but when you have light hitting your water at a shallow angle, you either loose it to reflection, or it is directed through the glass and not at your coral. Rebel's have more shallow angle light. In the most ideal case, your light should be distributed with near normal incidence.

 

Take a look at any of your tanks and look how much light LANDS where you want it to. I bet you have a lot of light hitting the glass

[evilc66]

My point still proves true. Regardless of the light lost at shallower angles, the Rebel maintains higher intensity at sharper angles than the XR-E, making its performance (other than lumen output) identical to the XR-E. The light output is measured directly above the die, not at the sides. A 100lm XR-E and a 100lm Rebel would both be as equally effective side-by-side, even though the Rebel has a 160 degree viewing angle.

[hyewiz]

while i was surfing the forums came across this LED Project.

it made out of 900 LED's

I wanted to share this 2 pictures with u

 

 

 

Materials : 50,000mcd white LED, 13,000mcd blue LED & UV LED, pre-drilled PCB board, copper wire, power supply

each PCB consist of 100x50,000mcd white LED, 100x13,000mcd blue LED & 25xUV LED.

There are no current-limiting resistor on the four PCB. Each PCB consist of 45 parallel x 5 series LED that drive by a 15VDC power supply. Each LED consume 3VDC at a low forward current or you can say I am under-drive those LED.

Total consumption of the 4 PCB is listed below and measured by FLUKE 79 Series II Multimeter:

DC: 15V 1.1A

AC: 223V 0.11A (~24W)

From calculation, 4 PCB x 45 parallel array in 15VDC, forward current on each array consume ~6mA.

[evilc66]

Ok, found the thread:

 

http://www.nano-reef.com/forums/index.php?...t&p=1191828

 

Even at 45deg of incidence, only 2.4% of light is lost. At 45deg, the Rebel still has higher intensity than the XR-E.

 

Yes, there is wasted light with the Rebel. But does it make the XR-E outperform it? No. Up to 45deg (90 total, same as the Cree) the Rebel has the same if not more light output at certain angles. It's just that there will be some spillover from the wider viewing angle.

 

Take a look at the datasheets for the two LEDs (page 8 for the XR-E, page 20 for the Rebel). The XR-E light output falls like a rock the further you get from center. The Rebel keeps it's light intensity up for a lot longer as it moves away from center.

[Gomer]

Take this picture for what I am talking about.

A majority of the light on that LED setup that is spilling out through the glass, out the top, and anywhere byt landing on the coral.. That amount increases for an increasing cone angle. I'm not just talking about reflection or internal reflection once in the water.

 

 

Wouldn't it be nice is 90% of the light lands without reflection on your coral/sand?

 

 

[coolwaters]

lol hey thats my picture.

 

the was extruded acrylic i was using. my new one is cell-cast which is worst cuz its super clear.

im pretty sure thats was just 4 high power LEDs...but they were K2s so its now efficient...about 40lm/watt

it still beats my 15w T8

[evilc66]

Gomer, don't you see that if you had two LEDs with the same output, one XR-E, one Rebel, both LED's would put a similar amount of light INTO the tank. The only difference is that because of the wider viewing angle of the Rebel, there is some spill at wider angles. THERE IS STILL THE SAME AMOUNT OF LIGHT GOING INTO THE TANK!!!!!

 

I guess I'm going to need to get some pictures done to illustrate my point on this one.

 

The only thing that the picture illustrates is that optics would make a wide viewing angle LED better than an LED with a tighter viewing angle because you are now refocusing the "wasted" light back into the same viewing angle as the Cree. (I think that made sense )

 

To be continued (with pictures)

[Gomer]

Gomer, don't you see that if you had two LEDs with the same output, one XR-E, one Rebel, both LED's would put a similar amount of light INTO the tank. The only difference is that because of the wider viewing angle of the Rebel, there is some spill at wider angles. THERE IS STILL THE SAME AMOUNT OF LIGHT GOING INTO THE TANK!!!!!

 

I guess I'm going to need to get some pictures done to illustrate my point on this one.

 

The only thing that the picture illustrates is that optics would make a wide viewing angle LED better than an LED with a tighter viewing angle because you are now refocusing the "wasted" light back into the same viewing angle as the Cree. (I think that made sense )

 

To be continued (with pictures)

 

 

One of us is dense and I am not sure who yet LOL. It could be me!

 

Lets make this extremely exaggerated fr the point I am trying to make.

 

2 LEDs.

Completely identical Luxeon K2s..

except one is lambertian, one is batwing.

Both with identical lumen ratings.

Both are magically waterproof.

Both are submurged just below the surface of the water

Both have zero optics.

 

Which LED has it's light getting to your coral and which has the light going out the glass? The "narrow" lambertian, or the "wide" batwing?

[evilc66]

Thats kind of a poor example. When I get some time later tonight (hopefully) I'll show you what I mean.

 

Please don't take anything I have said wrongly. This "conversation" has been pretty interesting for me. It will benefit everyone in the long run as they will know how to properly look at LEDs for this application.

 

I hope my little illustrations will help to clear things up.

[Gomer]

Thats kind of a poor example. When I get some time later tonight (hopefully) I'll show you what I mean.

 

Please don't take anything I have said wrongly. This "conversation" has been pretty interesting for me. It will benefit everyone in the long run as they will know how to properly look at LEDs for this application.

 

I hope my little illustrations will help to clear things up.

 

 

how about instead of my first example, you consider a mag flashlight. widebeam= rebel. narrow= cree. Fix the distance and adjust to a narrow beam such that the liht intensity matches the footprint of the tank. Now for the rebel, make teh maglight more wide beam.

 

The integrated light didn't change, but the amount of usable light changed.

[Ben314z]

Yay for constructive debate! It's great to see people discussing heated issues without throwing insults around or turning the thread into a flame fest.

[Gomer]

Yay for constructive debate! It's great to see people discussing heated issues without throwing insults around or turning the thread into a flame fest.

 

LOL. Atleast on my end, it isn;t heated at all There isn't even a debate since it is an objective topic, not subjective. The issue right now is 1) are we talking about the same problem. 2) if yes, who is missunderstanding it (if not both!)

[evilc66]

LOL. Atleast on my end, it isn;t heated at all There isn't even a debate since it is an objective topic, not subjective. The issue right now is 1) are we talking about the same problem. 2) if yes, who is missunderstanding it (if not both!)

 

 

Hopefully once I get pictures up things might make a little more sense.

[kydsexy]

does someone want to build me a LED lighting?