46" DIY LED Build Thread
- Thread starter davidpesce
- Start date
davidpesce
New member
At first I built a 10v regulated circuit using the 7810 chip with two capacitors. Then rapidled found a supplier somewhere in china with 10v regulated power supplies. I'm on my phone but if you go to their site and look at their dimming stuff you will find it.
jfl14609
Active member
I love the setup you have there the only thing I am curious about is the fact that its in an enclosure. everywhere I have read the biggest thing is air around it. even though you have fans doesn't putting it in that enclosure kid of cut back the effectiveness of the heat sink
davidpesce
New member
I was super worried about temp and it's exactly why I didn't include the meanwells in the enclosure. I'm running them so under powered that they don't heat up a lot. heatsink is at 78 degrees and leds are low 80s (81-83).
davidpesce
New member
And the PAR results are in... These were taken with the glass top on...
Here is a pic of the tank now after a 75g swap (with gl*******s overflow)
Results!
Sorry about the colors, it's hard to see some of them. Any questions just ask!
Here is a pic of the tank now after a 75g swap (with gl*******s overflow)
Results!
Sorry about the colors, it's hard to see some of them. Any questions just ask!
davidpesce
New member
Blue results, still with the glass top on...
Initial pic
PAR results:
Initial pic
PAR results:
filly469075
New member
what kind of optics are you using?
davidpesce
New member
No optics, they aren't necessary if you have the LEDs spaced appropriately.
I do have one or two spots were the infamous LED "spotting" is occurring towards the top of the highest rockscape, but other than that, nada.
Willistein
Active member
Very nice design and build! As far as heat removal, the heatsink and fan configuration inside the fixture is actually much better than an open air heatsink without a fan. ~150 watts is not a lot of heat to remove either.
Impressive PAR as well. I would like to see the tank if you're going to have a show and tell day
Impressive PAR as well. I would like to see the tank if you're going to have a show and tell day
davidpesce
New member
Impressive PAR as well. I would like to see the tank if you're going to have a show and tell day
I think there is supposed to be a club meeting on Saturday, but if not I'm around if anyone wants to stop by.
Henry Colf
New member
Very cool thread... I'm getting leds soon....I can't wait!!!!!!
davidpesce
New member
I got a message from Jason (jdoenumber2): "Were gonna do a meeting at ABC next sunday. 530-600."
Whoops, now that I read it again... looks like it's Sunday, not saturday! I can't make it Sunday. Doh!
Do you think Saturday is enough of a heads up to get people over here?
jfl14609
Active member
I am really impressed by this fixture as it basically goes against all of the "rules of thumb" I have read and works awesome. I love not having to use the optics as that's the biggest issue with the leds getting coverage. The only thing I am curious about is if they would penetrate the depth of a system like mine without optics. what are your thoughts my tank is 30 inches deep.
davidpesce
New member
See, this was a gray area for me. If I understand optics correctly, it concentrates the beam into more of a focused area so the light will penetrate further. But a side-effect of having optics is needing to raise the light fixture up higher above the tank. Hence defeating the purpose of having optics.
When I built this, I bought the optics because that's what everyone said to do. I haven't used them at all.
That being said, I thought about making an array with LEDs without optics on spots where the rockscape is high and LEDs with optics on spots where it's down to the sand. I haven't tried this, but with the general understanding I have of optics I think it would work. Would this be something you could do on your tank?
Willistein
Active member
If you don't have additional optics, the LEDs will emit 180 degrees so you'll get light straight out the sides even. Most of the energy is still directed forward though, which is why these Crees and others still work pretty well. The little plastic optics come in many flavors and you can pick your angle of light based on the tank needs. Jeff, you may have optics that have too tight of a beam (small angle).
davidpesce
New member
I think it'd be worth an experiment. If you remove the optics on the spots where the rockscape is higher you will be able to lower the fixture without spotting.
Even without doing that, you could try putting the fixture as it is closer to the water and see what the PAR readings are at the bottom.
The other concern I'd have with the LEDs you're using is that they're the lower output ones. I think they (XREs) are putting out around 220 lumens where as the XPGs are outputing 345 lumens. This is just a guess with no factual backing, but with less output I'm guessing it'll penetrate the water less.
Thoughts?
jfl14609
Active member
I know at the time the ones in my fixture were the highest output leds available. I will play some once I can get my hands on the par meter. I know for a fact that right now I am getting more light on the bottom of my tank than I did with three 250 watt 20k radiums and with those my par was around 100 so I would assume it will be higher. I am just thinking that if your fixture which is similar to mine only smaller scale is shooting par readings in the 80 range at the bottom if you put the same bulb on a tank thats 9 inches deeper its going to drop. But I defiantly see an advantage to being able to lower it and get better coverage. Can't wait to get some readings and see
