DIY LEDs - The write-up

[der_wille_zur_macht]

I'm not sure I had the same results with just Blue LEDs.

On my wife 20g nano, we initially used only Blue/White since we were using 120vac "led-bulbs" and RB wasn't available... we got really nice actinic pop from various corals using just the blue lights. Of course later we added 4 royal blue crees and the pop from those was much stronger, but I don't think its entirely fair to say Blue leds give no pop.

To be clear, I'm talking about Cree XR-E, XP-E, and Luxeon Rebel blues. If your 120v "LED bulbs" were using something else, that probably explains your different results.

 

[The Grim Reefer]

Thanks for the info guys.

I noticed another thing on the Cree site. Looks like you could even tweak the color based on the temp of the heat sink. According to their graph the blues maintain their output a lot better as the temp goes up, probably not the best way in the world to tweak colors, just saying.

How many LED's do you think it would take to cover a 120?

I am still thinking about converting one of the 17,000 T5 rigs I have laying around to a T5/Led Hybrid but with a nearly 300.00 power bill with no tank running I am thinking about going green.

 

[der_wille_zur_macht]

Thanks for the info guys.

I noticed another thing on the Cree site. Looks like you could even tweak the color based on the temp of the heat sink. According to their graph the blues maintain their output a lot better as the temp goes up, probably not the best way in the world to tweak colors, just saying.

True - color depends on the LED's inherent color properties, but also temperature AND drive current. I'm gonna sound like a broken record, but IMHO the best practice is to get a small number of a few different colors and experiment over your own tanks.

How many LED's do you think it would take to cover a 120?

A standard 4' 120? For a typical mixed reef application? Maybe 80 - 100. Depends on intensity you want, drive current, height above the tank, optics, etc. etc.

 

[The Grim Reefer]

Etc. Etc. Etc. Standard 120.

I am thinking this is going to be a mainly softy and LPS tank so not looking for blazing output.

Next question. On the Meanwell drivers I assume those have to be adjusted for current and voltage on setup? Does the temp play into those adjustments?

 

[der_wille_zur_macht]

Etc. Etc. Etc. Standard 120.

I am thinking this is going to be a mainly softy and LPS tank so not looking for blazing output.

Probably more like 60 - 80 then.

Next question. On the Meanwell drivers I assume those have to be adjusted for current and voltage on setup? Does the temp play into those adjustments?

There are two "classes" of mean well commonly used: The LPC and the ELN.

From the LPC class, the LPC-35-700 is the most common. It's preset at 700mA, no adjustments, and no dimming. It's a 48v driver so it can essentially handle 12 HP LEDs (13 or 14 if you use low-drop LEDs and like to push limits.)

The ELN model commonly used is the ELN-60-48. It's also a 48v driver, so 12 LEDs, but it can push up to 1.3A current (which would fry the LEDs we commonly use). There's an internal trimpot to set a drive current. Also, an internal trimpot to set max voltage, but for our applications, you can (and probably should) ignore the voltage trimpot.

The ELN-60-48 comes in two types: D and P. D is dimmable via 0-10v analog DC signal. P is dimmable via 10v PWM signal. In both cases, you MUST provide a signal - a 0v signal (nothing connected to the DIM circuit) means the driver will remain off. You also MUST adjust the internal current limit trimpot to something safe for your LEDs, since the range that pot covers goes well into "danger zone" territory and you don't want to find out it came from the factory set too high AFTER you've fried LEDs.

Temperature really doesn't play into the adjustments or daily operation of LED rigs. Basically, people typically over-design their heatsinks and use fans, which means the operating temp is going to be very reasonable, LED color will be accurate, efficiency will be good, and life will be good.

 

[The Grim Reefer]

Probably more like 60 - 80 then.



There are two "classes" of mean well commonly used: The LPC and the ELN.

From the LPC class, the LPC-35-700 is the most common. It's preset at 700mA, no adjustments, and no dimming. It's a 48v driver so it can essentially handle 12 HP LEDs (13 or 14 if you use low-drop LEDs and like to push limits.)

The ELN model commonly used is the ELN-60-48. It's also a 48v driver, so 12 LEDs, but it can push up to 1.3A current (which would fry the LEDs we commonly use). There's an internal trimpot to set a drive current. Also, an internal trimpot to set max voltage, but for our applications, you can (and probably should) ignore the voltage trimpot.

The ELN-60-48 comes in two types: D and P. D is dimmable via 0-10v analog DC signal. P is dimmable via 10v PWM signal. In both cases, you MUST provide a signal - a 0v signal (nothing connected to the DIM circuit) means the driver will remain off. You also MUST adjust the internal current limit trimpot to something safe for your LEDs, since the range that pot covers goes well into "danger zone" territory and you don't want to find out it came from the factory set too high AFTER you've fried LEDs.

Temperature really doesn't play into the adjustments or daily operation of LED rigs. Basically, people typically over-design their heatsinks and use fans, which means the operating temp is going to be very reasonable, LED color will be accurate, efficiency will be good, and life will be good.

Cool, thanks. Time to get serious. Guess I really should dig the tank out of the Garage and get it set up.

 

[Neogenocide]

people typically over-design their heatsinks and use fans, which means the operating temp is going to be very reasonable.

I can attest to this. I did the "I'll get that since that is what everyone else is using", and when I opened the box last night, holy cow was I in for a surprise. Yes I looked at the dimensions, but never really got out a ruler and thought hard about it. Lets just say a 10"x10" heatsink it a lot larger than it sounds, not to mention the weight. I'm actually kind of afraid that I may have to rebuild my hangers to support more weight. There is no doubt in my mind that this thing could be jam packed with LED's and still run cool.

Scott

 

[dnahas]

The ELN-60-48 comes in two types: D and P. D is dimmable via 0-10v analog DC signal. P is dimmable via 10v PWM signal. In both cases, you MUST provide a signal - a 0v signal (nothing connected to the DIM circuit) means the driver will remain off. You also MUST adjust the internal current limit trimpot to something safe for your LEDs, since the range that pot covers goes well into "danger zone" territory and you don't want to find out it came from the factory set too high AFTER you've fried LEDs.

First off, RANT, We need a Reef Central Wiki. Thank You.

Where is the good info on how to accomplish the dimmable designs? I have searched, I am :hmm3? I don't have an APEX yet and want to do something simple until I drop another few hundred $'s.

 

[der_wille_zur_macht]

First off, RANT, We need a Reef Central Wiki. Thank You.

A wiki format would actually work well for this. In lieu, keep your eyes peeled on Reefkeeping magazine for the next few months:

http://www.reefkeeping.com/joomla/index.php/reefkeeping-blog

Where is the good info on how to accomplish the dimmable designs? I have searched, I am :hmm3? I don't have an APEX yet and want to do something simple until I drop another few hundred $'s.

This thread will get you started:

http://www.reefcentral.com/forums/showthread.php?t=1793374&highlight=meanwell

Basically, for either version, if you want them to just run (at 100%), you connect them to a 10v source. For the "D" design, if you want to actually dim it, connect it to a big pot and a 10v source. For a "P" design, connect it to something that can generate a 10v PWM signal - either a simple 555 circuit, or a microcontroller, etc.

 

[TheFishMan65]

Temperature really doesn't play into the adjustments or daily operation of LED rigs. Basically, people typically over-design their heatsinks and use fans, which means the operating temp is going to be very reasonable, LED color will be accurate, efficiency will be good, and life will be good.

Man is that all takes for a good life. Can you solve work peace next? :lol:

 

[der_wille_zur_macht]

LED life. Your own life is up to you. :lol:

 

[HeneryH]

p.s. I just threw a quick model of the Mean Well together. Not perfect, but quick and good enough for spacially visualizing a build. It is to scale. I'll post them to the 3D Warehouse for easy access if you want them.

 

[widmer]

Lets just say a 10"x10" heatsink it a lot larger than it sounds, not to mention the weight.

:beer: I have the same 10.05" form factor heatsink, only in 1.25" strips because yes it is huge :celeb1:

 

[ReefEnabler]

To be clear, I'm talking about Cree XR-E, XP-E, and Luxeon Rebel blues. If your 120v "LED bulbs" were using something else, that probably explains your different results.

I actually tried to test this out a bit ago on my tank by covering up the royal blue XR-E's and only looking at the Blues. The blues were able to pop greens and some oranges a bit like zoas but not red montis, and things like already blue milles really get lost in the mix so it does give a much duller presentation by itself compared to RB. So expect a more limited actinic reponse but there is something.

I would've taken pictures, but I'm not able to accurately depict color in this blue range with any of my cameras stock settings, and I feel its a crapshoot once we start comparing raw edited manually adjusted photos.

 

[The Grim Reefer]

I actually tried to test this out a bit ago on my tank by covering up the royal blue XR-E's and only looking at the Blues. The blues were able to pop greens and some oranges a bit like zoas but not red montis, and things like already blue milles really get lost in the mix so it does give a much duller presentation by itself compared to RB. So expect a more limited actinic reponse but there is something.

I would've taken pictures, but I'm not able to accurately depict color in this blue range with any of my cameras stock settings, and I feel its a crapshoot once we start comparing raw edited manually adjusted photos.

If you camera has a landscape setting try that. My cannon does and it give the most accurate recreation of aquarium lighting I've ever been able to get.

 

[Iwishihadgills]

Would
x24 CREE XR-E Q5 Cool White
&
x24 CREE XR-E Royal Blue

put out enough lumens to grow sps in a 57 gallon rimless?

I wanna do two fixtures like reef addicts.

thanks

 

[der_wille_zur_macht]

Iwish, depending on optics, mounting height, drive current, etc. - yes, that should be plenty. For reference, Soundwave used the same 48 LEDs on his 75g and has posted photos showing good colors and growth on SPS. In your tank it should be more than enough.

 

[captstinky]

Somehow I missed out along the read; for those mounting LED stars to the heatsink using nylon screws, are 1/4" 4/40 recommended or 6/32?

 

[stugray]

I use the 8/32 nylon screw.

Just ordered a few hundred from Mcmaster-Carr:

94609A197 : NYLON ROUND HEAD SLOTTED MACHINE SCREW, 8-32 THREAD, 3/4" LENGTH

&

90295A110 : NYLON 6/6 GENERAL PURPOSE FLAT WASHER


ONE THING I just learned:

The optics need space to be attached to the star.

The way I chose to put on my nylon screws and where I chose to solder on my wire are not compatible with the optics.
OK for now as I dont NEED the optics, but do a dry fit with the optics before screwing down & soldering your stars.

Stu

 

[widmer]

Wow actual screws made out of nylon? You don't worry that at some point they might come loose due to the nylon threads, causing a slight air gap between the star and heatsink and allowing the star to overheat?