46" DIY LED Build Thread

davidpesce

New member
All this talk about LEDs reminded me of my promise to post my build thread for the LED fixture I created.

Supplies:

LEDs
- 24 Cree XP-G 3w LEDs (Cool white)
- 24 Cree XR-E LEDs (royal blue)

Drivers:
- (x4) Mean Well ELN-60-48P dimmable driver
- (x4) power cords

Heatsink:
- (x2) 23" x 4.25" x 1.05" (LWH) aluminum heatsinks

Dimming:
- (x2) 10K Ohm linear potentiometer
- 10v regulated power supply

Cooling:
- (x2) 92mm fans
- 12v power supply
- Arctic silver thermal paste

Misc:
- red 18 gauge wire
- black 18 gauge wire
- soldering gun
- screws for holding in LED stars

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Starting a dry run on soldering the LED stars. I did not put the thermal paste on yet. But I did screw them down to get the wire length accurate.

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Everything dry fitted! The LEDs alternate in color, starting at the top right is blue, then white, then blue....
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Then I took everything apart and used just a dab of thermal paste on each star and screwed it into place.

Still running at less than full power. The blues at 700ma
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And the whites (under powered) at 1000ma
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Just a note about the whites, DON'T LOOK DIRECTLY AT THEM WHEN YOU'RE BUILDING IT! I had stars in my eyes for at least half an hour afterwards.
 
Just a note about the meanwell drivers. Just inside the power cord (you can see a white circle next to the blue wire). That is the SRV2 where you want to adjust the power.
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Full test with everything in it's final position.
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Just a note, the alligator clamps are indispensable! I got two packages of them at harbor freight for really cheap. Came in handly while testing things out.
 
nice work! :) I wanted to do that when I was looking at light options but chickened out in the end lol Keep the pics coming!
 
Then I took a 48" Current USA PC light fixture (thanks CF!) and ripped the guts out of it.

Then using a step bit drilled fan holes in the top and mounted the 92mm fans.

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I also drilled a hole in the back so the wires could run behind the fixture without being seen.
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I drilled additional holes at the ends of the heatsink fins so I could run more wire and mount the heatsink to the casing.

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This is a pretty ghetto way of doing it, but it go the job done at the time. It allowed me to tighten the heatsink up to the brackets and then cap them off with copper grounding caps. I'd like to make some custom aluminum fittings when I build my next one specifically for the CurrentUSA fixture.

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Here it is all put together!
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You'll also notice I pulled the CurrentUSA build in fan out of the fixture as well. No need for it. The LEDs run at 81 degrees F and the heatsink at 78 degrees F.

here it is with the plastic splash guard back on it.
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Still testing it out.

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I ran it like this for over an hour and no overheating.
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You'll notice the holes I drilled into the fixture for the power cords. Oh and those awesome alligator clips!

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If you have any questions, feel free to ask! I'm curious to try out harder corals and see how the LEDs fare. I was worried about the SPS, but after a few weeks of growth I am pleasantly surprised!
 
Minus the fixture. Did you purchase everything retail? What was the approximate cost?

Total cost of parts ordered: $644
Total cost of parts actually used: $516
Cost of busted fixture: $20

$536 total cost

Took about 16 hours to build. Could easily do it in half that now that I've done it once.
 
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