# planning an LED system: comments welcome



## Dave-H (Jul 29, 2010)

Hello all -

At long last I have found a way to get a custom canopy done for my tank. It should be completed in the next week or two. Now I can move on and plan the lights that I'll install to it. 

I am very much liking the idea of an LED setup, both for energy efficiency and heat reduction but also because I love the idea of being able to adjust the lights using a dimmer. It seems that the dimmable setup would really help in dialing that 'just right' balance of light/co2/ferts. 

I am hoping to get some ideas of how this setup could work so that I can decide whether to build it myself or not. I am somewhat handy, but inexperienced with electricity and lighting. I contacted Catalina and they say they can make me a custom setup, and I'm seeing a few retrofit type fixtures on the internet. So, I'm hoping to devise a good plan and have it done by the time the custom canopy is ready.

In hopes of getting some great advice, I wrote up the below notes that describe my aquarium and what I am hoping to accomplish. Any input is much, much appreciated!

Lighting Objectives and notes:


To create a lighting system that will provide a good aesthetic effect (i.e light color/warmth) and provide support for plant growth with minimal electricity consumption.



To configure the lighting for minimal heat production. This aquarium is prone to heating up during the summer, mainly due to hot lighting fixtures. The LED lights should be configured to run at lower power to produce less heat, and will have ventilation fans built into the canopy to further reduce heating up of the tank.



Lighting the tank evenly is more important to me than getting a shimmer effect, so I am considering using a larger number of less powerful LEDs.



Variable brightness will facilitate easier adjustment and help to balance light/ferts/CO2 in the tank. I would like this fixture to be able to provide anywhere from 30 mms to 80 mms at the substrate.


Description of the Tank

The tank is a 54 gallon bowfront corner tank. There is a rim on the top of the tank with a plastic flange that covers 2 of the corners. So, the opening on top of the tank is shaped like this:










It is 20 inches from the substrate to the surface of the water. It is 29 inches from the substrate to the underside of canopy. So, if the heatsinks/mounting puts the actual LEDs about an inch from the underside of the canpoy, that means that the LEDs will be approximately 28 inches from the substrate.

This aquarium is equipped with a pressurized CO2 system. Liquid ferts (micro/marco) from rootmedic are used 3 x weekly. 

The tank contains a variety of small fish/shrimp and some medium light plants. 

Questions:


My intention is to make the light brightness adjustable so that the effective PAR at substrate can range from low-light to a high-medium light. The ability to produce high light is not necessary. One benefit of this is that at the intended light level (medium) the LEDs will not be running at full power and should produce less heat and last longer. Does this mentality make sense and is 30-80 mms a good range of light for this objective?



One problem with a corner bowfront tank is that it’s tricky to light and most fixtures won’t fit will on it. I am hoping to solve this with a triangular LED fixture with many LEDs spread out over the entire range.
DIY or have it made?

thanks everyone!


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## Hoppy (Dec 24, 2005)

I will try to use my data on cheap Ebay 3 watt LEDs to design a LED layout that will do what you want.


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## Dave-H (Jul 29, 2010)

thanks hoppy - I was hoping you would chime in 

There are two concepts that I'm having trouble with, maybe someone can point me to the right information.

1) I don't really understand the optics that are sometimes used. What exactly do they do and how to I decide if I need/want them or not?

2) With regards to the color/temp of the lights - I'm a bit concerned that the LED lighting won't have that nice warm and natural color that T5 lighting has. Are there any guidelines for choosing the right light types? I'm still not quite getting how it works.


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## IWANNAGOFAST (Jan 14, 2008)

optics are used to focus the light, so if you want a wide spread I would not use the optics. This is good in reef tanks where you'd want to focus a lot of light on 1 specific coral or something like that. 

What I would be worried about in a triangular set up is the middle would be lacking in light. Maybe you could do something like this


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## jasonh (Oct 26, 2003)

IWANNAGOFAST said:


> optics are used to focus the light, so if you want a wide spread I would not use the optics. This is good in reef tanks where you'd want to focus a lot of light on 1 specific coral or something like that.
> 
> What I would be worried about in a triangular set up is the middle would be lacking in light. Maybe you could do something like this


I would worry that it still wouldn't be very even. Best bet would probably be an even grid over the tank.

Regarding optics, they are useful if you want the fixture suspended high up over the tank. Basically they will concentrate the light into a narrower beam so you get less spread and can mount higher up. I've seen reef tanks with LED pendants mounted 3-4ft above the tank. Using optics allows them to be mounted that way while keeping the intensity and minimizing light-spill into the room. (see here: http://reefaddicts.com/content.php/70-LED-pendent-build )


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## Hoppy (Dec 24, 2005)

The Cheap 3 watt EBay LEDs wont work for a 28 inch distance from the LEDs and wanting 80 mms of PAR. At 750 mAmps, which requires a better heatsink arrangement than I used, and the LEDs spaced 2 inches apart in every direction, you would still get only about 40 mms of PAR. And it would require about 140 LEDs, clearly not economical. Being a generic LED of unknown exact dimensions, getting optics for them would be difficult too.

I think for a 28" distance from LEDs to substrate, Cree XP-G would be a better choice, but I don't have the data needed to design a layout using the method I used for my light.


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## Dave-H (Jul 29, 2010)

Well, the underside of the canopy is about 29 inches from the substrate, but that doesn't mean that I couldn't build a brace/bracket to suspend the fixture a few inches lower if need be.

Are there guidelines to how far from the surface of the water this kind of fixture should be? I am also having a hard time knowing how much more powerful the XPG series will make the light, and if I have a good chance of getting the desired PAR using those emitters.

I wonder if 25 or 30 of these would do the trick. This whole kit is $420 so it would be a bit more to add the dimming functionality, but perhaps I could do it cheaper. Right now I'm still trying to get general idea of what I need.

So far I've learned that the distance between my canopy and the substrate is going to be an issue.


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## jasonh (Oct 26, 2003)

Dave-H said:


> So far I've learned that the distance between my canopy and the substrate is going to be an issue.


May be a good use for optics


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## Dave-H (Jul 29, 2010)

Optics would be fine by me, I think. 

I'm looking for some good data that will basically tell me which LED with which optics, etc. is needed to provide the desired PAR at 28 inches and how much spread there would be. It seems like that data would be available, but I'm only finding bits and pieces.


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## Hoppy (Dec 24, 2005)

No question that Cree XP-G LED will do what you need. The question is how many you need. And, at what current to run them which means what heatsink design you need. Assume you run them at 1000mAmps. At that current you get about 325 lumens vs. the approximately 120 or so from the EBay ones I used. So, all else being equal, you would get about 2.7 times the PAR at any distance than what I got with the EBay ones. So, a 2 inch spacing should give you about 110 mms of PAR at 28 inches. Increase the spacing to 3 inch and you should get about 90 mms of PAR, which is about the max that you want.


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## IWANNAGOFAST (Jan 14, 2008)

With optics I'm sure you could get to your desired PAR levels, I just would worry that the spread wouldn't be too good.


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## Hoppy (Dec 24, 2005)

I was using the assumption that uniform lighting was an important criteria, which means no optics. With optics you get smaller diameter cones of light, so less overlap of adjacent LED's cones of light, and less uniformity, but with higher PAR. I haven't even tried to figure out how to design with optics in the mix.

You also wanted good color: I'm using 50-50 white and warm white, and it isn't a harsh look at all, much better than with just the whites.


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## Dave-H (Jul 29, 2010)

Well, if they were 3 inches apart and covered just about the whole tank it would take 35 Cree XP-Gs. 










If these are the LED we are referring to, that's $245 just for the LEDs. If it does what hoppy says it should do and I made it dimmable, I'd really have a nice setup!


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## Dave-H (Jul 29, 2010)

Just to keep exploring this and ball-parking the cost:

I am seeing dimmable drivers for the 3w Cree LED's in the $25 range, and I'd probably need 3 of them. Then I'd need various wiring, solder, etc. as well as a couple of fans to fit into the canopy.

What is confusing to me is the heatsink. I understand what a heatsink does and why it's used. For a setup like the above, it's going to be tough to find something the right shape. I saw heatsinks that were 4 inches wide and come in long lengths - perhaps I could cut them to size? Any easy options for this?


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## redfishsc (Aug 29, 2010)

If you are using all white LEDs, please DO NOT fear "spotlighting" with 60 degree optics (all you need). 


For a 60 degree optic, every inch down you go, you get 1 inch of circular light coverage. 

So, at 6 inches away, every LED puts out a 6 inch circular beam. At 10 inches, 10" spread. 15" away, 15" spread. When you add up the LEDs you have over the typical tank footpring, that's pretty good coverage.

As long as you don't have your LEDs spaced very far apart (no more than 4" or so apart if you can help it) then you should be fine if your array is suspended about 6-12" from the surface. Give or take. 


I think 20-30 Cree XPG, in a combination of neutral and cool white would look VERY good and work well for you. 

If you prefer the really warm sunny look, you can use warm whites and cool whites. I'd avoid using warm and neutrals together since I think it would look too yellow/orange. Would be fine for PAR but butt ugly IMO. Warm whites are very amber. 


For what it's worth, don't put line of LEDs close to the sides of your tank. Keep the LEDs on the sides/front/back a good 4-6 inches from the edge.


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## Dave-H (Jul 29, 2010)

Very interesting, thanks.

Now, what about retrofitting this to the inside of the canopy? Do people typically fasten the heatsink directly to the underside of the canopy? It seems like that would block airflow around the heatsink and defeat it's purpose.


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## IWANNAGOFAST (Jan 14, 2008)

hmm... very very interesting indeed. Maybe I'll grab some optics to up my par a little bit over my hairgrass area


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## Hoppy (Dec 24, 2005)

Dave-H said:


> Very interesting, thanks.
> 
> Now, what about retrofitting this to the inside of the canopy? Do people typically fasten the heatsink directly to the underside of the canopy? It seems like that would block airflow around the heatsink and defeat it's purpose.


How you mount a LED light is totally up to you. You can make the heatsink look good enough to serve as a outer case, and not use a wood hood over it. You can use the wood hood a the case and install individual heatsink strips to it. You can make a heatsink assembly that is functional, but not good looking and attach that in the hood. And, probably other ways too. I'm not sure what would work for you since the last I heard you had a full wood hood underway, with the top hinged so you could get to the tank for maintenance. With a large array of LEDs installed in that it could block access to the water unless it attaches to the "lid" of the hood. Figuring all of that out is part of the fun.


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## redfishsc (Aug 29, 2010)

Hoppy's 100% right, you can do this any way you want as long as you can get reasonable air flow. 


Being a cabinet maker, I prefer to dress them up with some lumber . I have already build the enclosure for my 45g cube build. I haven't build the stand yet, but the LED array will be on a 7X12 heatsink, and the pendant they are housed in is made from 3/4" A-1 birch plywood. The pendant is just a simple, mitered corner 16" cube box. 


LED heatsink will go on the bottom half (held in place by wooden cleats, it will just rest on them). On hole cut in the back with a fan for air movement (and fans on the heatsink for cooling). 

Then, there will be a 1/4" thick false bottom sitting over the LED array (3-4" clearance from top of the array to the false bottom). The LED drivers and timers will all sit inside the area. The very top will be left open; won't be visible to folks under 6'6".


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## shawnhu (Jan 23, 2009)

Dave,

You could save considerably if you purchased your LEDs from some other sources, such as groupbuyled.com you can easily reduce your price by $60-100 in LEDs.

The LEDs that you were looking at are the higher lumen, cool whites. Most people base the lumens and PAR measurements of the CREE XPGs based on the neutral whites, which is 122 lumens at 350mA.

You could definately use less LEDs, and use less power by lowering your leds closer to the water surface, or by using optics.

I was hoping to get around 100 PAR at 20" for my 46G bowfront, by using 28-30 XPG neutral whites running at 650mA. I would estimate that my build would be completed sometime in April. Hopefully, someone near me could lend me a PAR meter by then and see how many lumens I get, and to see if my calculations are on "par" or not.


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## redfishsc (Aug 29, 2010)

shawnhu said:


> Hopefully, someone near me could lend me a PAR meter by then and see how many lumens I get, and to see if my calculations are on "par" or not.


The PAR meter won't tell you lumen output, only micromols of photosynthetically active radiation.


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## Dave-H (Jul 29, 2010)

WOW what a great site! That knocks quite a bit off the budget, so I think I'm definitely doing this! The site had a really good explanation of how/why optics are used.

So far the Cree XP-Gs seems like the way to go. I will plan on having them between 3 and 4 inches apart (I might set one up and test with the PAR meter before finalizing this), and use 60 degree optics (also not sure about that).

Now on to the heatsink part. Man those things are HEAVY and since I'm covering a huge area under the canopy it could bring 20 pounds of heatsink into my canopy. That could get tricky so I need to plan that part. I noticed that some people use a piece of sheet metal to hold the emitters then the heatsink behind that. That could make the design more flexible. Also, I could use thin strips, like if the emitters were 4 inches apart I could use pieces of heatsink that are just over 4 inches wide and just put 3 or 4 strips in the canopy, would would probably work well. I am planning on building in 2 small fans (intake and exhaust) so I'm not that concerned about heat issues, I'm concerned about the weight and how the heatsinks will be attached to the underside of teh canopy.

This is starting to look good!


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## mylittlefish (Oct 5, 2010)

Do more bulbs than you think is ALMOST good.......... it will Not be enough.


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## Dave-H (Jul 29, 2010)

Huh?


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## mylittlefish (Oct 5, 2010)

Dave-H said:


> WOW what a great site! That knocks quite a bit off the budget, so I think I'm definitely doing this! The site had a really good explanation of how/why optics are used.
> 
> So far the Cree XP-Gs seems like the way to go. I will plan on having them between 3 and 4 inches apart (I might set one up and test with the PAR meter before finalizing this), and use 60 degree optics (also not sure about that).
> 
> ...


What site ?


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## Dave-H (Jul 29, 2010)

This one!


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## Dave-H (Jul 29, 2010)

So let's see where we are so far:

Rough parts list:

1) 30 x CREE XP-G = $146.10 from ledgroupbuy.com

2) 30 x CREE XP-G Optics = $44.70 from ledgroupbuy.com

3) Thermal Adhesive = $6.99 from ledgroupbuy.com

4) Dual fan system = approx $26.00 from various sources

5) 4.230" Wide x 50" Long Heatsink = 62.50 from heatsinkusa.com (I'd rather cut it into small strips and leave gaps than have them make one huge heatsink, since this is already going to be super heavy). With dual fans I'm considering trying to scale back on the heatsinks as much as possible.

6) Power supply: Next step is to figure this part out!

So far thats $287 and still a few pieces to go.


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## shawnhu (Jan 23, 2009)

Dave, I think you can get cheaper lenses elsewhere, like rapidled.com. You'll also need drivers, which I've found rapidled has a good selection, at fair prices. Combine the shipping, and you're looking at a good deal for the lenses and drivers from rapidled. The extra savings could go towards my new setup =D


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## Hoppy (Dec 24, 2005)

For heatsinks you could use http://www.heatsinkusa.com/products/10.000"-Wide-x-2"-Long-Heatsink.html which would be a lot cheaper and lighter - for 50 inches of length you would need 5 of those - making a 2" x 50" strip when fastened together with an aluminum bar along the 2 sides. I see no reason at all to even consider a solid one piece heatsink.


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## Dave-H (Jul 29, 2010)

Hoppy said:


> For heatsinks you could use http://www.heatsinkusa.com/products/10.000"-Wide-x-2"-Long-Heatsink.html which would be a lot cheaper and lighter - for 50 inches of length you would need 5 of those - making a 2" x 50" strip when fastened together with an aluminum bar along the 2 sides. I see no reason at all to even consider a solid one piece heatsink.


Ah my old, tired brain! Yea obviously that would be easier to work with, lighter, cheaper. Can you cut these aluminum heat sinks easily?


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## VaultBoy (Nov 11, 2010)

with a hack saw and some patience it should be easy enough to cut, ill be watching this thread closely as i have a caorner tank that i have been thinking about building an LED hood for but the triangle shape makes everything weird in my head... i am a plumber and i think in squares and circles


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## redfishsc (Aug 29, 2010)

Aluminum is pretty easily cut using woodworking saw blades as long as they are carbide tipped (most are, nowadays). 

Just cut slowly and wear safety goggles. You can use a miter saw, table saw, or circular saw. Just beware of kickbacks-- don't make a cut on the aluminum if you wouldn't make it with plywood or lumber.


Can also be cut with a jigsaw, just not quite as cleanly.


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## Hoppy (Dec 24, 2005)

An ordinary hacksaw also hand cuts aluminum extrusions fairly easily. And, you get good healthy exercise doing it. However, not all aluminum is the same. Aluminum extrusions are always an alloy, often 6061 aluminum, which is very hard when hardened to the T6 condition. It can be surprisingly hard to cut, and it is tough, tends to "gum" up the blade, and has very sharp edges after being cut. Just don't expect it to be old fashioned soft cast aluminum when you think about cutting it.


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## redfishsc (Aug 29, 2010)

^They certainly aren't as easy to drill as other aluminum products I've used. That's why I seldom drill/tap and use adhesives instead.


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## Dave-H (Jul 29, 2010)

I did it again in Photoshop, this time to perfect scale. If the LEDs were exactly 4 inches from the rear walls and 3 inches apart it would look like this:










Maybe remove that whole row that is closest to the front glass. That would make it 26 LEDs in total.


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## Hoppy (Dec 24, 2005)

I would remove that row closest to the curved front glass. You don't really want good plant growth right up against the glass anyway, and the light tends to encourage GSA and GDA. I think this will work very well.


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## Dave-H (Jul 29, 2010)

Now it looks like this. I added the 2 inch wide heatsink to scale.


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## Steve001 (Feb 26, 2011)

Here another site that you may find useful.
http://www.candlepowerforums.com/vb/index.php
Look at the led sub-forum


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## Hoppy (Dec 24, 2005)

Now that you have settled on 26 LEDs, and the pattern they will be in, plus the heatsinks, what circuit do you want to use? All in one series string, in two parallel 13 LED strings, in two independent 13 LED strings, etc.? When you decide that, then you can pick out the LED driver(s) you need. Of course, first you need to decide if all the LEDs will be the same color temperature, or, if not, what mix you want.


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## Dave-H (Jul 29, 2010)

Well, first I want to make sure that 26 LEDs is going to be enough. The last thing I want is to build this thing only to find it's not as powerful as I had hoped. I'm getting the feeling that if each of the LED's has a 60 degree optic on it it should be just fine as far as PAR goes. With regards to spread, the 60 degree optic should allow plenty of spread to make the light nice and even with 28 inches of space between the lights and the substrate (according to what little I've learned).

I'm thinning to go 50% white and 50% warm white.

As for power/wiring I have noticed that the corner tank really has unusual needs, because the front is so different from the back. Not just wider, but different - driftwood is clumped towards the back which means there is very little open substrate to light up and the lighting could be a bit dimmer to avoid algae back there. The front glass is basically a big lawn, so lots of light needed there. The middle is mixed.

So, I think I'll try to have 3 dimmable zones - the front, middle, and rear. 

There is also a problem with the diagram that I made. I made that to-scale diagram to show the opening on the top of the tank. But, there is a plastic flange along the rim, and as you can see it blocks the front left and right corners of the tank. The problem is that the glass really does go all the way to the corner, so I might want to add one more LED on each side just to ensure that the corner is well lit. Then again, there will be tons of light bouncing around in the corner so maybe I can skip that.

Here's an updated diagram with an LED added to the front corners (which now isn't looking like it will be a good idea), the corners of the tank better indicated, and 3 zones of lighting shown. 

With 3 dimmable areas I'll really have nice control over the lights!


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## Hoppy (Dec 24, 2005)

I think you will get plenty of light in the corners without the two extra LEDs. Remember the light striking the inside of the glass is largely reflected back into the tank (from the outside surface of the glass), and the light entering the tank is "focused" by the refraction at the water surface, so you get more PAR with water in the tank than without.

My LED light gives me almost uniform PAR across all of the substrate, even though my calculations indicate that the PAR will fall off quite a bit at the glass. That is the effect of the reflection off the glass back into the tank. This is dramatically shown by having the light on an empty tank, and seeing how much light goes out into the room, then filling the tank and seeing how little light goes into the room.

I think 3 zones would be superfluous, too. I can see putting the rear ones on their own circuit, but I see no reason to separate out those not at the back. I would make that decision based in part on how well I could match the number of LEDs to a driver - if a driver will handle 24, for example, in two parallel strings of 12, I would set up the remaining ones, located at the back, on a separate driver. If you really plan to run 700 mAmps, you should avoid parallel circuits though. In a parallel circuit setup if one LED fails open circuit, the other parallel string gets double current, or 1400 mAmps, which will kill most LEDs. If you use 500 or less mAmps, a parallel circuit arrangement makes good sense to me.


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## Dave-H (Jul 29, 2010)

Hoppy said:


> If you really plan to run 700 mAmps, you should avoid parallel circuits though. In a parallel circuit setup if one LED fails open circuit, the other parallel string gets double current, or 1400 mAmps, which will kill most LEDs. If you use 500 or less mAmps, a parallel circuit arrangement makes good sense to me.


hoppy, 

Reading your comments above makes me realize I need to better understand how the drivers/power works before I get started. I haven't held a soldering iron in a long, long time!

I do want to keep 3 zones, though, because of the driftwood setup that I have and because I do think it will be useful with the corner shaped tank. Certainly it's not needed but I just sorta kinda want it that way


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## Hoppy (Dec 24, 2005)

An LED driver puts out a controlled constant current, which can be adjusted either by removing the case and turning a screw, or by wiring in a dimming circuit. It provides up to whatever maximum voltage it is designed for, in order to maintain that current. If 2 strings of 12 LEDs in series, for example, are then powered in parallel by the driver, the constant current is shared by the two parallel circuits, equally if they are identical circuits. So, if one circuit is opened up, by breaking a wire, pulling a solder joint apart, a LED failure, etc., no current flows through that parellel circuit, making all of the driver's constant current flow through the other circuit that is wired parallel to it.

Meanwell drivers produce 48 volts, for example, so they can handle 16 LEDs which have a "forward voltage" of 3 volts each. But, the drivers may have an adjustment screw inside the case that lets you raise or lower that 48 volts to anything between zero and about 51-52 volts. This lets you also drive 16 LEDs when each has a forward voltage of almost 3.25 volts. When the LEDs are cold they have a higher forward voltage, so their nominal 3 volts may be 3.2 volts when at 60F temperature. I ran into something like that and had to adjust my current driver to a higher voltage.


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## redfishsc (Aug 29, 2010)

Yeah it took me a while to get the hang of just how different a constant current driver is, compared to a constant voltage source like a wall-wart. 



Hoppy said:


> An LED driver puts out a controlled constant current, which can be adjusted either by removing the case and turning a screw, or by wiring in a dimming circuit.



Just to add to this, Hoppy is referring to the Meanwell ELN60-48 model. This model in particular has a small screw "SRV2" inside that allows you to make adjustments the current, but this is a "set it, and forget it" adjustement. 


If you want to be able to "dim on the fly", you'll want to get the ELN-60-48D (same numbers, just ends with D). You'll have to build a simple dimmer circuit using a 6 to 9v DC wall wart and a 10K potentiometer (really not hard), and we can explain how that works in more detail if you're interested. 


Hoppy--- are you aware of any way to dim LEDs on a constant-current driver that has absolutely no current adjustment options on it? There are a lot of LED drivers that have no such adjustements, and I'm not aware of a way to dim LEDs on them, but would love to know if such a thing exists


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## Dave-H (Jul 29, 2010)

I did a quickie test in the tank tonight with the PAR meter and the Powerbrite 3 x 1 watt LEDS have much better penetration than a T5NO. I have a good feeling about LED for deep tanks.


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## Hoppy (Dec 24, 2005)

redfishsc said:


> Hoppy--- are you aware of any way to dim LEDs on a constant-current driver that has absolutely no current adjustment options on it? There are a lot of LED drivers that have no such adjustements, and I'm not aware of a way to dim LEDs on them, but would love to know if such a thing exists


I looked around for some mention of how to do that on the internet, and didn't find it. And, I can see no way to do it, since it have to defeat the circuit in the driver. Of course you could install a fake parallel circuit of resistors, and vary that resistance to vary the proportion of the total drive current that is left over for the LEDs. That is very wasteful. The wattage rating of the resistors (potentiometer) gets pretty high too.


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## VaultBoy (Nov 11, 2010)

in order to dim non dimmable LED drivers couldn't you use a variable resistor in series with the string of LEDs? I am no electronical engineer personally i am using these drivers

http://www.sureelectronics.net/goods.php?id=1035

i will be running cheap ebay 3w LEDs in 6 strings of 5 @ 24v input voltage they will run at 685mA max and are PWM dimmable i will be using an arduino to provide day noon and moon cycles but you can use any 0 - 5v power source for the dimming. For my very budget concious project these are excellent @$4.75 shipped i bought an extra one just to play with


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## VaultBoy (Nov 11, 2010)

hoppy your too fast  you answered my question before i asked it


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