Another NC 28 LED Retro

[willp2]

After months of plotting and scheming I finally was able to build my LED retro for my Nano Cube 28CF.

My mission was to keep it as simple and quite honestly as cheap as possible.

The parts:
12 Blue 3W 90 degree SemiLED 200lm
12 Cool 3W 90 degree Cool White SemiLED 200lm
4 Sure Electric 3W Drivers http://www.sureelectronics.net/goods.php?id=1035
1 Old Dell laptop power supply
556 based PWM for dimming
2 potentiometers for dimming
Thermal tape
3/8 inch aluminum plate / heat spreader

I miscalcualted when specing this all out and didn't realize that I need a couple more drivers or a bigger power supply to drive the LED’s at the full 700ma. So at the moment the best I can do is 350ma. So I'm currently running 4 drivers with 6 LED's each. I'll be adding a couple more drivers soon.

I wanted to see how this would do heat wise with just mounting to a plate and no external fins. I am still running a couple of quiet fans in the hood so there is good air flow across the plate. At full power after a couple of hours its around 115f in the hottest spots right on the heatsink and quite a bit less everywhere else. I’ll probably add some U channel to the back to get some more surface area when I add more power later. BTW - that plate looks filthy in the pics. It was actually quite smooth and clean.

The Sure Electric drivers are nice little units. Built nice and work well. I ended up stuffing them in the compartments in the back of the hood, that's not shown in the pics below.

So running at 350ma, I am getting about 130 PAR on the sand. Not bad I think as I can push a lot more to them if I want. Compared that to the old CF bulb that was way hotter and only gave me about 30PAR on the sand. Intereting also is that I have the LED’s mounted high in the light box from the old CF light, so there are sides all around. That and the directional properties of the LED’s make far less spilled ligaht in the room.

Not bad for $150 bucks, eh? Should be even nicer when I add the extra drivers and push the LED's to 700ma.

***EDIT*** My orginal PAR numbers were based on a quick measurement in one spot at the end of a long night. Tonight I had to pull the lid to move around some of my wiring as I ran out of time when I originally put it together and things were a bit sloppy. So I took the opportunity to remeasure my PAR numbers.

Tonight after spending some time cleaning the glass on the splash shield under the LED's and taking measurements all over the bottom I averaged 130 PAR across the sand.

Then I added some 60 degree optics and I got a 287 PAR average across the bottom.





See if you can spot the mistake(s) in my wiring

[LotsaFishies]

very nice!

[superman858mm]

is it comparable to 150w or 250w mh? thanks

[willp2]

I'm not sure honestly, maybe someone else can chime in on how those PAR numbers translate? I suspect that its on the low side of a 150w mh as it is now. When I add the additional drivers and can push them all the way to 700mah and / or add optics I think we'll be looking at a much improved story. These things are running at only half their rated current at the moment.

[laffingcrow]

Very nice Will; I'd bet you don't ever need to run them at full power.
I'm also interested to know how the #'s translate to MH.
Anyone with a PAR meter running Halides???

[willp2]

I am very glad I made these dimmable. I'd hate to be stuck with the color of all the lights on all the time. The blue is pretty strong and makes the tank look purple at full power. I've seen this on other tanks and now I realize that this is likely a setup that couldn't be adjusted. I just back off the blue a bit to dial in the color. I find myself changing it slightly thoughout the day to match the lighting in the room.

[Acefspds]

Nice man I have a 28g 150w hqi but lack the PAR meter. I am really interested to see the difference. If someone has a PAR wants to stop by I will give you a frag or something if we can test my lights. Would be with water in the tank.

[Acefspds]

Doing research 97 PAR is probabley less than a 150w hqi in a NC28. Id guess your looking at 175+ PAR on the sand in a 150

http://www.atlantareefclub.org/forum...t=4695&page=2w hqi

[willp2]

Thanks. Tonight I had to pull the lid to move around some of my wiring as I ran out of time when I originally put it together and things were a bit sloppy. My originally PAR number was just me dropping the PAR meter on the bottom at the end of a long night.

Tonight after spending some time cleaning the glass on the splash shield under the LED's and taking measurements all over the bottom I averaged 130 PAR across the sand.

Then I added some 60 degree optics and I got a 287 PAR average across the bottom.

[willp2]

I should add in case it isn't clear from what I said above, I am still running at half power on these things. When I get my new drivers in a couple of weeks I should be able to bump up output quite a bit.

[willp2]

I love this, its heating up outside and I am getting ZERO heat into the tank from the LED's! I have a simple computer fan blowing over my filter and so far its keeping the temp nice and comfy. The room temp was 84 when I got home, tank was 78.

[Acefspds]

What are the prices for each light that you are gonna order? I am interested now that you say the par is alot higher. At 287 thats probabley more then my 150w HQI. I am all about getting my tank cooler since I do not run a chiller.

BTW how is all the corals under the LED's?

[willp2]

Just so its clear, that 287 PAR number was with optics. Without optics it was around 130 average at half power on the LED's. So both numbers should go up once I can run these things at full output.

I've only been running this for a week, but things are already going crazy and I've still got it turned down a bit as I'm trying to acclimate over time. I've got new growth and better color on just about everything already. Frankly I'm sort of shocked that I can see a difference already.

You must live near the coast if you’re not running a chiller and you are running HQI. My tank was getting hot just with the PC’s.

The LED's are $3.75 a piece, optics $1 each.

[Acefspds]

Optics are just lenses basically?

[willp2]

Yes it's just a lens that sits on top of the LED. They just focus the light into a smaller area. Most LED's put out light in something like 120 to 160 degrees, so a lot of light is going sideways. In my case the LED's are already pretty good at 90 degrees. The optics brought those down to 60 degrees