DIY LEDs - The write-up
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fernandokng
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Thanks kress.
Very cool webrage. Where did you get the black acrylic box? i've been looking for something like that.
Very cool webrage. Where did you get the black acrylic box? i've been looking for something like that.
I made the fixture same way Soundwave did but instead of using a project box, I mounted everything along the inside edges of the fixture. I used clear acrylic to enclose all the opens on the fixture. I used self-etching primer on aluminum frame part of the fixture "this way you paint will not flake off", after it dried I added six coats of black semi-gloss paint to the frame. I also painted one side of the acrylic sheets that face inside the fixture.
The LEDs are space 1 1/2" apart from each other and I'm getting great light spead covering the whole tank, no spotlight effect.
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What would the downsides be (for a larger tank) to using flashlight style individual drivers (~$1/LED, like http://www.dealextreme.com/details.dx/sku.3146) with a 5V DC PS (something like http://cgi.ebay.com/5V-DC-50A-250W-Regulated-Switching-Power-Supply_W0QQitemZ370194651976QQ) with perhaps an inline non light-emiting diode to drop the voltage to that of a 3-cell battery?
Besides non dimmabilitly and the extra soldering... Is the premise sound?
Besides non dimmabilitly and the extra soldering... Is the premise sound?
kcress
New member
Welcome to Reef Central mother.
Interesting angle!
It would probably work. I see four issues.
1) Impelmentaion. We seem to have enough hassles getting the LEDs and their optics reasonably mounted. Now you add these extra per LED details.
2) We need the LEDs thermally connected to the heatsinks. These driver boards would probably be in the way in that regard.
With flashlights a lot of work goes into conducting the LED heat into the flashlight's surrounding cylindrical case. Not sure how to implement that on a large flat heatsink.
3) 4.5V is not a common output on power supplies.
4) You would need a huge number of wires as now each LED would need a parallel set of wires coming from the supply. You could have 60 wires coming to the power supply instead of, say, 10 or 16.
webbrage great job!
Interesting angle!
It would probably work. I see four issues.
1) Impelmentaion. We seem to have enough hassles getting the LEDs and their optics reasonably mounted. Now you add these extra per LED details.
2) We need the LEDs thermally connected to the heatsinks. These driver boards would probably be in the way in that regard.
With flashlights a lot of work goes into conducting the LED heat into the flashlight's surrounding cylindrical case. Not sure how to implement that on a large flat heatsink.
3) 4.5V is not a common output on power supplies.
4) You would need a huge number of wires as now each LED would need a parallel set of wires coming from the supply. You could have 60 wires coming to the power supply instead of, say, 10 or 16.
webbrage great job!
Thanks, been lurking a long time!
1) Yeah, pain in the butt
2) I think the driver boards could simple live on the top side of the heatsink so they shouldn't make the heat dissipation issue terribly more difficult.
3) Apparently a company in Malasia makes a 5V 50A SMPS for about $50 shipped
4)I was thinking of simply running a +4.5V bus (if that is the correct term) down the length of the modules and using t-tap style piercing splice attached to a short lead to power the lights. The neg sides would simply get grounded to the HS .
You still have a solution that requires 3x as much soldering though. But it costs like $1/emitter rather than $4/emitter for buckpucks.
My mental exercise is because I'm thinking of doing a 92 reef, and lighting that thing is going to be a PITA. (I really can't fit a longer tank where I would like it).
kcress
New member
Have at it!
I would like to see the result. It certainly seems cheaper out of the pocket.
I want to see how you deal with the the drivers up on the top side where the heat sink fins are.
One more niggling point. You short that 50A supply anywhere and you will be.. um.. ah.. surprised. (unpleasantly!)
Your wires will be necessarily small to prevent strain damage to the drivers. Likely the resulting size will present enough resistance to the 50A, in a short circuit case, that it will happily continue to drive into the short. This will cause the wire to glow red or orange and set anything non-metal in the immediate vicinity on fire.
You should start thinking about fuses in each hot lead... Note too that drivers designed for a single or two flashlight batteries do not need fuses because a couple of small batteries are not deemed to have enough energy to start a fire. Price just go up? :{
I would like to see the result. It certainly seems cheaper out of the pocket.
I want to see how you deal with the the drivers up on the top side where the heat sink fins are.
One more niggling point. You short that 50A supply anywhere and you will be.. um.. ah.. surprised. (unpleasantly!)
Your wires will be necessarily small to prevent strain damage to the drivers. Likely the resulting size will present enough resistance to the 50A, in a short circuit case, that it will happily continue to drive into the short. This will cause the wire to glow red or orange and set anything non-metal in the immediate vicinity on fire.
You should start thinking about fuses in each hot lead... Note too that drivers designed for a single or two flashlight batteries do not need fuses because a couple of small batteries are not deemed to have enough energy to start a fire. Price just go up? :{
stugray
Premium Member
mother,
"I was thinking of simply running a +4.5V bus "
Then you would not be able to control the current through each LED as you do with a CC driver.
Now if we could find a 750mA CC driver in a surface mount package that works at 5V for under $0.50, then you would be in the ballpark.
The light I imagine for my 125G would have ~150 discrete LEDs.
Driving them all on a 5V Buss would require 150 CC driver circuits.
The CC buckpucks are cost effective because you can drive many LEDs in series.
Stu
"I was thinking of simply running a +4.5V bus "
Then you would not be able to control the current through each LED as you do with a CC driver.
Now if we could find a 750mA CC driver in a surface mount package that works at 5V for under $0.50, then you would be in the ballpark.
The light I imagine for my 125G would have ~150 discrete LEDs.
Driving them all on a 5V Buss would require 150 CC driver circuits.
The CC buckpucks are cost effective because you can drive many LEDs in series.
Stu
Yeah, in this case they're $1/each not $0.50, but would that be worthwhile?
For your 125 we would need $150 worth of them vs $500 for 25 buckpucks. But you would have 150 drivers to wire instead of 25.
Kcress,
How about if we put in like a 1 farad cap too, for smoothing?
So you would say that 250W as 5V50A is much more dangerous than 250W as 25V20A then? I'm fairly sure that 22guage wire will be a very quick acting fuse when shorted across either. The ultimate safety feature is the fact that there are these diode things that blow up in each circuit, no?But that's the kind of thing I was looking for. I'm pretty sure the PITA factor covers things though.
james3370
Premium Member
what depth tank do these typically put good par for??? a friend has a 36" tall tank (48x36x36) that she wants me to figure out the cost of lighting it via LEDs. should i use more LEDs spaced closer together or using them at 1000mA be sufficient? what about optics...yay or nay???
also, what ratio of white:royal blue would you recommend??? i was thinking 3:2 ratio?
also, what ratio of white:royal blue would you recommend??? i was thinking 3:2 ratio?
I want to say what an awesome thread. I have read this thread several times and have been convinced to go LEDs on my new tank which is in the planning stages.
Has anyone tried to use 10 watt LEDS??? I have been looking out on the web and they are suppose to have ~400 lums and be comparable to a 400 or 500 watt metal halide.
The downside is they cost $30 or $40 and piece which still cheaper than a metal halide light.
Has anyone tried to use 10 watt LEDS??? I have been looking out on the web and they are suppose to have ~400 lums and be comparable to a 400 or 500 watt metal halide.
The downside is they cost $30 or $40 and piece which still cheaper than a metal halide light.
If it was me I would go with at lease 72 LEDs to start out with using the medium size lens which would give you both coverage and penetration for that much depth. I would 3 sections of 24's, and believe it or not you will more happy if you 36 whites and 36 blues. Using the dimmers you can control the color levels of the blue real nicely.
You can always add more LEDs after if needed.
kcress
New member
I'll be building mine eventually for a 36" deep tank. I'll definitely be using optics to reach for the bottom.
lead; So far the 10watters don't really appear to be as cost effective. Less lumens more dollars... And harder to find optics for them too.
Yep kudos to Soundwave for starting it with a bang!
lead; So far the 10watters don't really appear to be as cost effective. Less lumens more dollars... And harder to find optics for them too.
Yep kudos to Soundwave for starting it with a bang!
Finally have mine to 99.9 % completion. Ended up using 6 CW and 6 RB on my all in one Mini Bow 7 nano. Man these things put out some light! I have a few pics of my build, but I am not anywhere close to the great stuff I have seen posted here, so I am not so sure about posting pics. We'll see.
Really a fairly easy project to do and fun too. I ended up cutting the heat sink in half for this project. I mounted two fans in my canopy blowing down across the heat sink. I also end up having a large enough slab of aluminum to put together another light for another nano down the road.
So far no issues.
I used:
700 mA buckpuck with external pot for the blue
1000 mA buckpuck with external pot for the white
MPJAA power supplies
Fans from my "surplus" box
I mounted mine in a canopy that I built for my tank which is stained black to match the base that the tank sits on.
Soundwave, again, great thread and great job!
Really a fairly easy project to do and fun too. I ended up cutting the heat sink in half for this project. I mounted two fans in my canopy blowing down across the heat sink. I also end up having a large enough slab of aluminum to put together another light for another nano down the road.
So far no issues.
I used:
700 mA buckpuck with external pot for the blue
1000 mA buckpuck with external pot for the white
MPJAA power supplies
Fans from my "surplus" box
I mounted mine in a canopy that I built for my tank which is stained black to match the base that the tank sits on.
Soundwave, again, great thread and great job!
fernandokng
New member
I'm planning to have 2 fans on each heatsink.
Anyone against putting one fan blowing down, and one blowing up?
Or should I do both down (soundwave)? Or both up.
Anyone against putting one fan blowing down, and one blowing up?
Or should I do both down (soundwave)? Or both up.
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