DIY LEDs - The write-up

[widmer]

The only thing I can think of is when soldering an LED for a project, I accidentally nicked the lens with the soldering iron. It didn't discolor the lens, but it did make a small divot that casts a shadow and makes the die appear to have a black spot. There goes 100 lumens :lol:

 

[S2minute]

Leds

Leds

Threw up an Album guys, if you care to pass some time. It shows the tank setup in the very beginnings also the current electric sucking Medusa i`m using...which the ballasts are now failing :hammer:

 

[kcress]

After running my rig for several weeks I pulled it down to do a little work on it. I noticed that some of the whites (normally a yellow color when not lit) had a black spot in what seemed like the middle of the lens or on the surface of the LED material. Looks like they are burned but they still light.

Anyone ever seen this before? I am only running at 833mA for LEDs rated at 1.5A.

I think I will replace them as a precaution.

Hi Henery.

That doesn't sound good.. :eek1:

Some questions if you would be so kind:

How high are they above the tank?

Do they have splash protection?

Have you used that spray sealant on them?

Can you touch the heatsink after an hour of running?

What kind of heatsink are you running?

Have you rechecked the current setting?

What are you using for a driver?

Thanks!

 

[CJO]

So what's the skinny on these LEDs?

Can you use any kind of LED because there are a lot of companies that sell various LEDs.

Possibly, but you need to do your research. Many of us have decided that it's best to use the most efficient LEDs due to their lower heat output and better output at the same energy level. At this point, that is the Cree XP-G, which is about to be superceded by the Cree XM series. There are some other good (efficient) brands out there like Luxeon. There are also some very cheap Chinese ones that you may be able to use, but the density you would need and the cooling requirements makes it impracticable.

Do they have to be a particular color or Kelvin?

This is still an ongoing discussion. Many people (me included) have started with a ratio of royal blue to cool white LEDs. Some people are switching out some or all of the cool white LEDs for neutral white. Others are also experimenting with adding other colors (red, blue, cyan, yellow, warm white, etc.)

I realize that 3W seems to becoming a standard. At least right now.

3W LEDs is really a misnomer, but the ones that are commonly called 3W are the ones that are being used.

Also I read somewhere that there was a company that put a patent on reef LED units to monopolize the market.

So what's the case, will we see a lot of new LED fixture startup companies that will hopefully help expand the market and lower the price?

It's true that there is an aquarium lighting company who has a patent on some of the technology used. They have successfully sued another company out of business but have taken no steps since then. It has been theorized that they are waiting until the other companies become more successful so that they can receive more money from a lawsuit, but right now it's just conjecture.

CJ

 

[agoutihead]

Possibly, but you need to do your research. Many of us have decided that it's best to use the most efficient LEDs due to their lower heat output and better output at the same energy level. At this point, that is the Cree XP-G, which is about to be superceded by the Cree XM series. There are some other good (efficient) brands out there like Luxeon. There are also some very cheap Chinese ones that you may be able to use, but the density you would need and the cooling requirements makes it impracticable.

I get so confused with Cree because there are so many different lines of their LED's I dont understand what the difference between all of the model #'s are.

Well my friend's wife works for a company that buys Korean LED's & they are supposed to be of very high quality, but are used in only commercial or industrial purposes. But they have all kinds of various fixtures & new bulbs all containing LEDs, I'm sure they're working on other variants of LED's at the main factory.

How can I tell if they would work good for reefing?

What exact specs should I be looking for?

They are the yellow jelly looking kind, the real high intensity ones.

Before when LED's came out they were like little bulbs, now they are this kind of jelly... I take it this was a huge advancement in LED technology? What is that yellow jelly actually?

This is still an ongoing discussion. Many people (me included) have started with a ratio of royal blue to cool white LEDs. Some people are switching out some or all of the cool white LEDs for neutral white. Others are also experimenting with adding other colors (red, blue, cyan, yellow, warm white, etc.)

Why are neutral whites now thought to be better over the cool whites? I thought the cool whites were more of a pure white, arent they?

What does adding spectrums of red do? (other than make it more yellow?)

I would be looking for a 20k look...

3W LEDs is really a misnomer, but the ones that are commonly called 3W are the ones that are being used.

Can you explain this a little more? So if they're not 3W, then what are they? Are the 1W, 1W then?

It's true that there is an aquarium lighting company who has a patent on some of the technology used. They have successfully sued another company out of business but have taken no steps since then. It has been theorized that they are waiting until the other companies become more successful so that they can receive more money from a lawsuit, but right now it's just conjecture.

CJ

What is the name of this company & when does their patent expire? I take it the company they sued was Solaris? (Was it the same Solaris that built that awesome glass AIO cube?)

That really sucks and I feel thats bad business. Really shows the greed of some filthy animals. They didnt invent LED's or saltwater fixtures, so they shouldnt be able to patent the entire idea.

We could have a lot more start up companies to help boost the economy coming soon with the LED sector.

They just put a cap on ingenuity.

 

[der_wille_zur_macht]

I get so confused with Cree because there are so many different lines of their LED's I dont understand what the difference between all of the model #'s are.

The datasheets are a good reference. All available on Cree's website.

How can I tell if they would work good for reefing?

What exact specs should I be looking for?

Typically, I would judge LEDs based on three criteria, in this order of importance:

1) Efficacy. For all but royal blue, this is typically measured in lumens per watt. A "good" white LED might be 100 lumens/watt. A REALLY good LED might be 140 lumens/watt. Personally, I wouldn't touch anything lower than these general numbers unless I got the LEDs for next to free and didn't plan on keeping the fixture very long. For royal blue, efficacy is typically measured in terms of radiant flux, i.e. mW/W. A really good royal blue might be 500 mW/W.

2) Color. MOST people consider the "classic" mix to be cool white and royal blue. Most cool white LEDs are somewhere around 6500k, in the bins we typically get. Most royal blue LEDs are in the range of 450 - 460 nm.

3) Appropriate packaging/optic selection/etc to allow for typical implementations. Some LEDs have no native optics, or are packaged in weird sizes, etc.

They are the yellow jelly looking kind, the real high intensity ones.

Before when LED's came out they were like little bulbs, now they are this kind of jelly... I take it this was a huge advancement in LED technology? What is that yellow jelly actually?

I have no idea what you're talking about with respect to yellow jelly, sorry. The class of LEDs that Cree X-Lamps and other commonly used LEDs belong to is typically called HP LEDs, i.e. High Power LEDs. This generally indicates an LED that typically runs over 1W of power, is SMT, and is designed in a way to allow for good thermal management.

Why are neutral whites now thought to be better over the cool whites? I thought the cool whites were more of a pure white, arent they?

What does adding spectrums of red do? (other than make it more yellow?)

I would be looking for a 20k look...

This is all very much personal preference, so you really need to experiment to determine what's best for you. Some people find that the "classic" mix of royal blue and cool white is a little washed-out looking, so some people are adding other colors into the mix.

Can you explain this a little more? So if they're not 3W, then what are they? Are the 1W, 1W then?

Don't get hung up on naming HP LEDs in terms of power dissipation. No respectable manufacturer does so, with good reason. A given HP LED might be run over a very wide range of power levels depending on the application or environnent. For instance, a Cree XP-G might be operating at 1W in one fixture, and 5W in another. Calling it a "three watt" LED is hence rather inappropriate.

 

[wld1783]

Hi Henery.

That doesn't sound good.. :eek1:

Some questions if you would be so kind:

How high are they above the tank?

Do they have splash protection?

Have you used that spray sealant on them?

Can you touch the heatsink after an hour of running?

What kind of heatsink are you running?

Have you rechecked the current setting?

What are you using for a driver?

Thanks!

+1

I have had the same thing running 12 XPG with a 1.3mA ELN 60-48D. I later tested the drivers and they were putting out much more than 1.3mA so I replaced the LEDs and dialed the driver down to 1000mA.

If the driver is adjustable and states 1.3 mA or more, still measure and adjust it. To qoute a great guy...

"Trust but verify"

Bill

 

[TheFishMan65]

Gee I expected more pages since I have been gone. Come on DFason what did you fix? Here is what I got working - finally.

With front back angling by group

and individual left right.

I currently have it running about 18 inches over the tank with 60 degrees optics on the center 8 LEDs. I think (we all know how well the eye works) this is about the same intensity I had from four flourescents. I will slowly add optics over time to increase intensity.

50/50 XR-E Royal Blue and XR-E Cool white at 500 ma.

 

[der_wille_zur_macht]

Pretty awesome. The first build I have seen that really takes advantage of individually aiming single LEDs.

Speaking of, I would throw a PAR meter under that rig if I were you. With that many LEDs essentially "concentrated" towards the same general area of the tank, you might be getting a lot more light than it looks like - especially with optics. I've repeated this example a bunch of times in here but again I will reference my experimental build on my 60g tank, where I essentially fried a bunch of high-light SPS by aiming a very small number of LEDs right at them.

 

[Taqpol]

Fishman, I haven't been paying too much attention to the LED forums, but I popped in today and your build was the first picture I saw. Holy crap, that is the slickest most professional looking DIY fixture I think I've ever seen!

I do agree with DWZM though, you might be focusing a lot of light on a single area. I have been having a lot of trouble with my tank, most of it non-LED related, but I really think that my 60 degree optics, 14" height, and high intensity caused a lot of coral bleaching. I am also of the opinion that something about focused LED light might effect the way PAR meters read the light (The sensor can't pick up all the light because of the angle, so it posts a lower PAR number then what the coral actually sees?) but I have no way to prove that. Regardless, for my build I might switch entirely to 80 degree optics.

Also note that because of the angle you will get a lot of light reflected off the top of the water, which for me resulted in a significant decrease in PAR at the far ends of the tank where I had my fixtures angled. Of course, you might also get better growth patterns with more angled light.

 

[The Grim Reefer]

Has anyone actually taken PAR readings with and without optics?

 

[CJO]

Has anyone actually taken PAR readings with and without optics?

I have. I don't have them in front of me, but 60 degree optics made a huge difference from no optics at all. IIRC, it was about a 100% (2x) difference.

CJ

 

[der_wille_zur_macht]

I am also of the opinion that something about focused LED light might effect the way PAR meters read the light (The sensor can't pick up all the light because of the angle, so it posts a lower PAR number then what the coral actually sees?) but I have no way to prove that. Regardless, for my build I might switch entirely to 80 degree optics.

I agree - corals in LED-lit tanks seem to often respond as if they're under more intense light than a PAR meter indicates.

Grim, at least a few people have done good comparative work with and without optics, but there are so many factors involved that IMHO you have to take each case one by one. There was a user who posted a build in the regular reef forum a number of months ago who did a good job - I think his username was santoki or something like that.

 

[TheFishMan65]

I must have been a bad boy - Santa did not bring me a par meter Right now I only have 1/3 with lenses and every seems fine (3 days). May have to see about borrowing the club meter. Thanks for the advice.

Grim - yes, but I can't rememberthe thread. I must like you try:
http://www.reefcentral.com/forums/showthread.php?t=1902716
http://www.reefcentral.com/forums/showthread.php?t=1761942
Seems like there was another one, but I can't locate it.

 

[kcress]

It was lacking around here. Good to see you back Fish.

And yes DFason don't be a turkey..:hmm3: Tell us what got your rig working so we can all benefit.

 

[The Grim Reefer]

WHat I meant was Actual PAR readings in a tank full of water, My bad. Light striking water in a direct line penetrates the water much more than light hitting at an angle which allows more of the light to reflect off the surface. I suspect in the case of 60 degree optics the real world gains are going to be crazy. Might have to order up some optics and play.

 

[der_wille_zur_macht]

Agreed 100% Grim - several of the people posting PAR results have taken the measurements in a manner where I feel they are not very meaningful. IIRC Santoki did his over a tank with water in it, and compared different optics. Here's his thread. I don't have the time to dig through it now but I remember his numbers seeming reliable:

http://www.reefcentral.com/forums/showthread.php?t=1761942

 

[The Grim Reefer]

Thanks for the link Willie

Don't have time to look right now but it looks like his first batch of readings were a comparison to wet and dry readings rather than wet with vs wet without optics. I'll dig deeper later.

 

[RCBrooke]

Has anyone had / noticed a light pulse after turning a meanwell driver (ELN-60-48D) off?

I finished the 3rd 12x string last night. 1st string is 12 xp-e royal blues, 2nd string is 12 xp-g (6nw/6cw),
and the third string is 12 xp-e royal blues. This last string comes on fine, dims OK, but right close to 7 seconds after I turn the power off I get a light pulse. The other two strings didn't pulse when I tested them. I checked and found no shorts to the heat.

Any thoughts?

Thanks,
Randy

 

[wld1783]

Has anyone actually taken PAR readings with and without optics?

LED Optics Test

The test fixture is a 24" LED Strip Kit custom assembled for Corbins Exotic Pets Pets in Buffalo Grove Illinois.

The Heatsink is a 24" x 8.46" from HeatsinkUSA. The LED strips are 6 XR-E Royal Blue/White and 4 XRE Royal Blue. The drivers are MeanWell 60-48D. The four Royal Blue strips are driven at full power (at 9 volts appx 580mA) in 2 parallel series of 12 LEDs. The other Royal Blue/White Strips are driven by a single MeanWell 60-48D adjusted to 750mA at 9Vdc

The drivers were adjusted and the input voltage was provided by a Radio Shack Enercell. Par was measured 24" above the fixture center mass and 24" centered but 12 "œ to the side. The meter was an Quantum Flux Apogee meter MQ-200. Watts were measured with the common KillaWatt meter.

No Optics

Driver Input........PAR@24"........PAR@24"........Watts
Volts DC..........Center Mass....Center + 12"

9........................214................142... ...........186
7.5.....................180................128.... ..........162
6........................155................100... ...........124
4.5.....................104.................82.... ...........84
3........................78..................58... ............49
1.5.....................32...................22... ............21

60 Degree Optics

Driver Input........PAR@24"........ PAR@24"........ Watts
Volts DC...........Center Mass.....Center + 12"

9........................355................150... ............186
7.5.....................310................131.... ............162
6........................242................78.... .............124
4.5.....................202................66..... .............84
3........................131................43.... ..............49
1.5......................60.................18.... ..............21

70 Degree Optics

Driver Input........PAR@24"........PAR@24"........Watts
Volts DC...........Center Mass...Center + 12"

9........................432...............170.... ............186
7.5.....................348...............158..... ...........162
6........................301...............140.... ............124
4.5.....................262...............95...... ............84
3........................171...............65..... .............49
1.5.....................74.................30..... .............21

80 Degree Optics

Driver Input........PAR@24"........PAR@24"........Watts
Volts DC..........Center Mass....Center + 12"

9.......................330................183.... ............186
7.5....................292................174..... ...........162
6.......................254................143.... ............124
4.5....................190................109..... ...........84
3.......................125................53..... ............49
1.5....................56..................33..... ............21