TheFishMan65
New member
I agree, but I was also thinking that he should get what suits his driver. They will run cheaper and cooler if he maxes out the driver since it will be lower current.
(Another) DIY LED Build - Linear Design
- Thread starter katchupoy
- Start date
Another idea for cooling. These are 12 v dc blower style fans. The fan venting side is marked as 3.1 inches by 1.26 inches. Here is the data sheet.
http://www.alliedelec.com/Images/Products/Datasheets/BM/ORION_FANS/ORION-FANS_5920137.PDF
Now I found an aluminum bar here..
http://www.metalsdepot.com/products/alum2.phtml?page=tube&LimAcc=
So how would taking that fan and mating it with a 3 inch by 1.5 inch by 1/8 inch thick rectangular aluminum bar do for cooling the leds? The bars would be $75 for 2 x 4 foot sections, the fans are about $25 each.
http://www.alliedelec.com/Images/Products/Datasheets/BM/ORION_FANS/ORION-FANS_5920137.PDF
Now I found an aluminum bar here..
http://www.metalsdepot.com/products/alum2.phtml?page=tube&LimAcc=
So how would taking that fan and mating it with a 3 inch by 1.5 inch by 1/8 inch thick rectangular aluminum bar do for cooling the leds? The bars would be $75 for 2 x 4 foot sections, the fans are about $25 each.
I have no idea what driver to use yet. I do want it to be dimmable.
The tank is 36"w x 18"d x 24"h. Its about 21" from water level to sand bed. This will all be in a canopy as well.
I don't want to have so much light that it will be running at %50 all the time. If that were the case I could have used half the LEDs ya know? I do know that I will most likely go slightly over board to play it safe since I can dim it.
What drivers are rated for use with 12 LEDs? Maybe I could make up half the tank and see how that goes?
The tank is 36"w x 18"d x 24"h. Its about 21" from water level to sand bed. This will all be in a canopy as well.
I don't want to have so much light that it will be running at %50 all the time. If that were the case I could have used half the LEDs ya know? I do know that I will most likely go slightly over board to play it safe since I can dim it.
What drivers are rated for use with 12 LEDs? Maybe I could make up half the tank and see how that goes?
TheFishMan65
New member
Well nick with a 36x18 I think you are right on the edge between 12-24. Are yiu getting reasonable growth now then try 12. No growth then I would try 24.
So using this idea (which makes sense to me) my 65g would be 36*18 / 36 = 18. If that's using 60/40 split on blue/white then I'd actually be using around 15-16 white LEDs only.
That looks nice! Seems like a fair price. I'm thinking that driver with 14 LEDs should be a good starting point? It says 48V though so that would only be 3.42V per LED which seems low? Would it be more efficient to go to a 12 LED system with that driver?
TheFishMan65
New member
3.4 volts might run the XP-G at 1 amp so you might want to give it a try.
I guess I should ask 2_zoa
When talking about his build that might be 12 LEDs. This started me trying to do some research since was contray to my understanding. I have poste severl of those, but just trying to get facts from other to try and find a "real" answer.
No all this depends on how much the LEDs are concentrated (they make LED lasers), but I am trying to find info on similiar area of what a MH covers.
You've been around, and read, and know more then I do about LED lighting.
I do think this is a "fair" starting point though. At least its not manufacture claims.
http://www.advancedaquarist.com/2007/10/review
Edit;
Here's another good one.
http://www.advancedaquarist.com/2010/2/aafeature2
Here's an old one, but it shows PAR readings for a 400 watt halide. Also the effect of glass shields.
http://www.advancedaquarist.com/2005/8/lines
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TheFishMan65
New member
I skimmed the article and they seem reasonable. No expert on what they say so I can't be sure.
Ok so here's a break down on parts and a plan. Let me know what you'd change, add or whatever.
I plan on building two units. Each will consist of the following:
Mean Well ELN-60-48D
10k Ohms POT for dimming
10V DC Adapter for dimmer circuit (only need one for both drivers correct?)
(12) Cree XP-G R5 Cool White 3W LEDs
The whole setup seems pretty straight forward. I see in the specs on the XP-Gs have a max rating of 1500mah. Is it best to run them at 1A? If I'm using a DC adapter for the Mean Well that's 9V will I be able to get 1A out of the driver?
Once I get my electronics figured out I'll start doing some sketches to see how I wan to place them over my tank to get some input from you guys.
I honestly think 24 LEDs will be way over board but honestly, there isn't much cost difference in running 18 LEDs vs 24 LEDs right? Basically just the LED/Optics cost. Will running the whole setup at %50 power shorten the life of the LEDs? If it doesn't then I'll build a 24 LED setup and then I can always use it in the future tank builds if need be.
Can I use this POT for dimming?
http://www.radioshack.com/product/index.jsp?productId=2062354
I plan on building two units. Each will consist of the following:
Mean Well ELN-60-48D
10k Ohms POT for dimming
10V DC Adapter for dimmer circuit (only need one for both drivers correct?)
(12) Cree XP-G R5 Cool White 3W LEDs
The whole setup seems pretty straight forward. I see in the specs on the XP-Gs have a max rating of 1500mah. Is it best to run them at 1A? If I'm using a DC adapter for the Mean Well that's 9V will I be able to get 1A out of the driver?
Once I get my electronics figured out I'll start doing some sketches to see how I wan to place them over my tank to get some input from you guys.
I honestly think 24 LEDs will be way over board but honestly, there isn't much cost difference in running 18 LEDs vs 24 LEDs right? Basically just the LED/Optics cost. Will running the whole setup at %50 power shorten the life of the LEDs? If it doesn't then I'll build a 24 LED setup and then I can always use it in the future tank builds if need be.
Can I use this POT for dimming?
http://www.radioshack.com/product/index.jsp?productId=2062354
Last edited:
TheFishMan65
New member
Running 50% will INCREASE the life since they will run cooler. Yes that pot will work =, but RS does not always have the best quality.
TheFishMan65
New member
We on RC try not to criticize but we are great at critiquing
SimonSKL
New member
Nick, I use two of those RS POTs in series to the dimmer circuit. First one to regulate the voltage to no more than 10v and the second one to dim the LEDs. The first one is set and forget. I understand this is not the best way to regulate voltage but it is the simplest way that I can understand and able to do. As far as RS products being not the best quality. I agree but when I get online with one of the electronic supply sites, I was totally lost. Their prices are very reasonable but I hate to pay $10 shipping for just a $2 purchase.
Ok Here's what I came up with. Top view of the tank. LED rails are 4" OC, LEDs are 2.5" OC (Is this too close?) and then I'll be running (3) 24" VHO actinics. I went this route because it gives me more options on running different VHO bulbs and still gives me 6' total length.
Front view using 60 degree optics on the LEDs. LEDs are about 3" above water line. It's about 24" from LED to top of sand bed. Looks like using no optics these LEDs have a 125 degree spread but that seems like it would waste A LOT of light?
This is the light at the water surface. Not exact touching each other with the 60 degree optics.
1" below water line the LEDs from each rail touch. Spread from front to back of tank is about 9" or so.
11" down from the water surface the LED spread will hit front and rear glass.
Thoughts? My only gripe is with the rear glass layout. If I have something within 11" of the water line in the back of the tank it won't be getting direct light. Would this be ok? I know once the light hits the water line the angle is skewed as well right? So this isn't the exact light path through the water.
I could move the whole assembly back an inch or two to help with lighting in the back of the tank where most of the coral will be. I also don't want to waste light over the overflow.
Front view using 60 degree optics on the LEDs. LEDs are about 3" above water line. It's about 24" from LED to top of sand bed. Looks like using no optics these LEDs have a 125 degree spread but that seems like it would waste A LOT of light?
This is the light at the water surface. Not exact touching each other with the 60 degree optics.
1" below water line the LEDs from each rail touch. Spread from front to back of tank is about 9" or so.
11" down from the water surface the LED spread will hit front and rear glass.
Thoughts? My only gripe is with the rear glass layout. If I have something within 11" of the water line in the back of the tank it won't be getting direct light. Would this be ok? I know once the light hits the water line the angle is skewed as well right? So this isn't the exact light path through the water.
I could move the whole assembly back an inch or two to help with lighting in the back of the tank where most of the coral will be. I also don't want to waste light over the overflow.
TheFishMan65
New member
Yes, I believe several have used the 1 inch angle as well.
