Current LED Project---what parts am I missing?

[titancrusher1]

I posted earlier about ideas how to get this done and i've put together a game plan on how to build a 9 LED Bulb at 10w each Fixture.

I know alot of you may not agree with these bulbs in terms of efficiency but this is more or less an experiment so bear with me! My goal is to make a thinner LED fixture that I dont have to hang and keep the profile minimum.

I've purchased 5 10W 12000k Cool Whites from Ebay

http://cgi.ebay.com/ws/eBayISAPI.dll...ht_2369wt_1144

and 4 10W 445nm Actinic/Blues from Satistronics

http://www.satistronics.com/10w-hige...ing_p2773.html

The light fixture itself is 72" long to coincide with my tank. starting at 4" in from one side i will be putting in an LED every 8". Should look like this

W for White B for Blue/Actinic


xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
x W B W B W B W B W x x x
x x
.............................................................................


The fixture will be 8" from the Water Surface....this is a random number I picked so if anyone has a better idea in terms of height let me know!

I will be powering them with a 12v 15Amp Power supply. The only thing I'm clueless to is what Drivers should I get if any? it sounds like my power supply is ample enough I dont need drivers so to say. As it is now, it sounds like I will be going from the power supply directly to the LED's. I'll be wiring Parallell.

Im thinking about putting in a Dimmer Switch as well :-)

Are there any components im missing? Any other things I'm missing or not paying attention to?

On a side note, you guys have been quite helpful!

[titancrusher1]

Okay, that diagram did NOT come out right lol.

[titancrusher1]

FYI

LED Specs:

Blue Actinics

Emitting color: 'Extreme Royal" blue.
Wavelength between 445-450nm
Deep blue and ideal for the rapidly growing reef lighting industry
Luminous: 150-200LM
Input voltage: 10-11V
Input current: 900mA
Power: 10W


Cool Whites:

High quality aluminum alloy material
SMD
Luminous Flux : 800-810 Lumen
Rated voltage: 10~12V DC 10W
Color temperature: 12000K Cool White
Forward Current (IF): 1000mA
Viewing Angle: 120 Degree

[der_wille_zur_macht]

Originally Posted by titancrusher1

I will be powering them with a 12v 15Amp Power supply. The only thing I'm clueless to is what Drivers should I get if any? it sounds like my power supply is ample enough I dont need drivers so to say. As it is now, it sounds like I will be going from the power supply directly to the LED's. I'll be wiring Parallell.

You MUST use drivers, or at the very least, some method to ensure constant current operation (i.e. correctly chosen power resistors). Otherwise, if you hook an LED to a typical voltage-regulated power supply, it'll either blow up the LED, blow up the power supply, or both.

Im thinking about putting in a Dimmer Switch as well :-)

Dimming MUST be done through your driver mechanism - you cannot use a typical "dimmer switch" you'd use on lights in your home, for instance. If you want dimming, you're best off getting a driver with a dimming function built in.

Are there any components im missing? Any other things I'm missing or not paying attention to?

Heatsink of some sort, plus fan(s) if necessary (a "10W" LED generates a LOT of heat on a small area, so cooling is a little more critical than a typically-used LED). Plus, mounting hardware, proper wiring, solder, and so on.

[titancrusher1]

I just finished chatting with the guys at LED Supply. Looks like I need 5 Buckpucks. I'm may be getting 3 of these

http://ledsupply.com/03023-d-e-1000p.php

and 2 of these for the Actinics

http://ledsupply.com/03023-d-e-700p.php

How would I attach a dimmer mechanism to all of this?

My heatsink will be the physical fixture itself. It's a 72"x3" piece of Tin basically with a 1" side height and a convenient lip for my plexiglass fabrication to slip in and offer some protection.

You think 8" would be high enough for the light spread?

[der_wille_zur_macht]

The pre-wired buckpucks have a pair of wires to which you attach a potentiometer for dimming control. Or, an active controller of some sort if you're going that route.

Not sure if I'm following your tin heatsink - can you provide photos?

It's going to be hard for us to predict the spread/coverage of those LEDs at that height because very few people have hands-on experience with them. Also, it's going to depend on what you're trying to accomplish with the LEDs - just light up the tank so you can look at it, or grow corals?

[titancrusher1]

This is basically the tin fixture what I purchased to mount the LED Lights inside of. Notice it has a lip that's perfect for slipping in a piece of Plexiglass in. Keep in mind the actual dimensions of mine are 1"x3.25"x 9'

http://www.homedepot.com/h_d1/N-5yc1...atalogId=10053

[der_wille_zur_macht]

There is absolutely no way that is going to be anywhere near adequate for the task, and it's the wrong material to boot. Please see the discussion in the other thread you started.

If you're looking for a cheap heatsink, take that back and get some angle aluminum stock. Home Depot carries it. It'll be much more appropriate for this application, and you can probably buy or fashion a channel shape similar to what's in that picture if you really want it.

[SpacedCowboy]

Originally Posted by titancrusher1

This is basically the tin fixture what I purchased to mount the LED Lights inside of. Notice it has a lip that's perfect for slipping in a piece of Plexiglass in. Keep in mind the actual dimensions of mine are 1"x3.25"x 9'

http://www.homedepot.com/h_d1/N-5yc1...atalogId=10053

What DWZM said, exponentiated.

Here's what I'm planning on using, based on tests I've been running on LEDs for the last few months:

Each of those Aluminium bars is 1" wide by 3" tall by 24" long, and I'm mounting a fan at either end to push/pull air through the hollow interiors. I'm also mounting them in a vertically-orientated fashion to get better heat dissipation by convection in the open air.

Each bar holds *6* LEDs, for a total of 24 in the entire unit (which is 24" deep by 12" across).

The final prototype I had of this got warm but not too hot to touch after 8 hours of continuous 100% (well, 100% of 70% capacity ) use, and the temperature-controlled fans were idling slowly, and (crucially, for me) silently.

A single piece of wafer-thin (0.556 mm!!!) steel is going to do diddly-squat to cool your LEDs, IMHO.

Simon

[titancrusher1]

Ok learning alot here. As stated in the beginning of this thread my goal is to create a Thinner/Low profile design (by order of the queen of the house :P) I'll be coming up with some ideas but feel free to input your own!

[der_wille_zur_macht]

Originally Posted by der_wille_zur_macht

If you're looking for a cheap heatsink, take that back and get some angle aluminum stock. Home Depot carries it. It'll be much more appropriate for this application, and you can probably buy or fashion a channel shape similar to what's in that picture if you really want it.

Go back to Home Depot and look for some of this:



It'll be in an aisle with general hardware, with other extruded metal shapes. You want extruded aluminum. Stick with 1/8" thickness. Choose a size that'll give you the dimensions you want, and bolt it together to form the shape you want. You should be able to pretty much re-create the U-channel steel that we've convinced you to not use, and you'll get vastly better performance.

If you are planning on putting acrylic across the face of the "box" then you will need to provide some means for good airflow. Drill holes near each LED and/or keep a fan running on the fixture.

[titancrusher1]

Thanks for the heads up! wow some of you guys are patient lol. I'll be looking for that aluminum piece. more questions to come....