DIY LED build for 75 to 90 gallon tank

[AlanM]

For fun, attached is my current design for 75 or 90. Basically a bigger Maxspect Razor with colored LED's added using input from the nano-reef.com full spectrum thread that I think ridetheducati posted a while ago. It's overkill for a 75, but not much more expensive and easier for me to get than a 20% smaller one for a 75.

 

I'd be running these Cree at 700mA instead of their rated max of 1500 because they're all on 3-up stars so the heat is a bit less distributed and they're harder to keep cool.

 

The goal is to get the three-up blues and whites and the three-up colored ones packed in pretty tightly to form kind of bright pendants on purpose rather than to spread them evenly along the heatsink by using individual emitters in a checkerboard type pattern.

 

When different colors are spread evenly with a few inches between you can get something derisively referred to as "disco" where the surface of the water makes the colored spots move around on the rocks and sand like in a night club. If you pack them in tight, then you get a bit less even coverage, but less possibility for a moving club-light effect.

 

At least that's the theory of the lighting "experts" over there at nano-reef.com. I buy it (and soon will literally buy it), but haven't tried it myself. I could use 3 individual heatsinks, but one long one leaves room to move things around, and the MakersLED heatsinks are really pretty. Not as pretty as the Razor, but nice.

 

I'd buy all of the LED's from LEDGroupBuy because they sell three-ups with optics that go on them. With 40 degree optics I can mount them 12-16 inches at least over the tank and get good light. I'd buy the drivers and power supplies from StevesLEDs because he makes PWM drivers that can be dimmed down to 1% unlike the Meanwell's which go dark at 10%.

 

Mostly I'm making it this complicated because I'm enjoying it and will have fun playing with the 4 channels of dimming.

 

Looks like total cost is going to be around $900 or so, which might still be too much for me, so I might end up paring it down a bit.

 

 

[Guest thefishman65]

Alan,

 

I designed a similar driver to Steve's. Many more adjustments (IMHO) since you like complicated. Cheaper per LED too. If you (or anyone else) are interested pleae PM me and I will discuss the difference (pros and cons).

[AlanM]

PM sent

[AlanM]

Posting this over here since I don't want to clutter up your group buy thread with questions. You said there that you have yours at 2.5 feet off the water.

 

I'd really love to mount mine high like that. I was planning on 12 inches with 40-45 degree optics, but since I've never done it before. I am only just calculating 30inch*tan(20degrees)= 11 inch radius on a 18 inch deep tank 12 inches above the water which will hit the glass, but only by a few inches.

 

Should I really be calculating by the FWHM of the lens or something and assuming that on a 40 degree lens has a FWHM of 20 inches and so 30inch*tan(10degrees) = 5.3 inch radius so lots of shadow around the edges at 12 inches for that lens?

 

I'm getting a rimless tank and I think it will look much better with them that high or higher. The reason I'm getting a rimless tank is that I want to see the contents: critters, rock, sand, and water with as few distractions as possible. Not a big light hanging above or HOB pumps or plumbing drilled into the side or whatever.

 

Maybe I should get 10 degree optics and recess them into the ceiling. 8)

[Guest thefishman65]

If the center is the maximum amount of light (lumens) then the Full width half modulation (for those that aren't following LED) is the point where the light intensity has reached 50%. Depends on the lens as to how sharp that is. So some light still comes past that angle.

 

Ever get out to Gainesville. maybe buy a few and play with the lenses.

[AlanM]

Right. Spec sheets for the Luxeon and the Cree lenses as shipped show what looks like a FWHM (Full Width Half Maximum, not modulation. You're a PWM electronics guy, but I do particle scattering and diffraction) in a 120 degree spread with the 50% intensity point at +60 and -60. If a 60 degree lens was similar with a gaussian 60 degree and the 50% intensity point at +30 degrees and -30 then I was calculating it right and I'd end up with 50 percent of the center intensity at a radius of 17 inches from center on the sandbed if they were 12 inches above my water (30 inches above the sand).

 

That seems pretty large, I'm just not sure what most people use as the intensity boundary of the spread, if you know what I mean. Do they calculate where the light drops by 75% and call that the useful spread?

 

Guess you also have to account for the fact that the interior surface of the glass will reflect some back into the aquarium if it's coming in at a shallow enough angle, so you probably get less spill than the first order geometry would indicate.

Edited December 31, 2012 by AlanM

[Guest thefishman65]

Ok, you got me beat! But ah ha, I can answer your question. It is called a PAR meter

[AlanM]

Right. I should just give in and do the full dynamical scattering calculations on the bare LEDs, and then I'll tell you what the par meter will measure. 8)

 

Actually if I got a ray tracing algorithm up I bet people would find it useful. Will ask the math guys at work how hard that would be to simulate.

[AlanM]

By the way, have you seen these? The pwm LED nerds on reef central are a flutter over them. So cheap, and such a large voltage range. Apparently really tiny too.

 

http://store.bravoelectro.com/ledpowersupplydriverconstantcurrent-ldd700hbrleddriver956vdcin252vdcout700maconstantcurrent-p-1824.html

 

 

[Guest thefishman65]

Those are nice wish they had those a few years ago. The data sheet only says 36 volts, so maybe 9-11 LEDs.

[AlanM]

Been looking at power supplies for those drivers online and it looks like Steve's are so cheap he must get them off the back of a truck. A 100w 36v looks like about 55 dollars compared to Steve's 400w 24v for 50. Not sure the cost savings for the drivers running at 24v so 6-7 per driver would make up for it with wires going all over. Your 8 channel 24v driver for $50 is comparable.

 

A 400w 36v power supply for around $50 would change the deal, though.

[AlanM]

Wait, this says up to 52v out, so a 48v power supply should work?

 

http://www.meanwell.com/search/LDD-H/LDD-H-spec.pdf

[Guest thefishman65]

The 36 or 48 would work with the Meanwell LDD. It will not work with the CAT it is limited to 25 volts. I think you have it, but don't want to confuse others .

[lnevo]

I've been researching a similar build for my 65g for a while. Thinking about either 66 or 77 LEDs. But I think I'll go with the solder-less from rapidled since they really aren't much more expensive than the 3ups or straight LEDs. I'm also looking at Steve's for drivers and power supplies. I'm on the fence though with the makers heat sink or something much cheaper...especially since I found thermal tape What's your plans for mounting drivers and PS? As part of the fixture? Remote enclosure? How about wiring...trying to figure out a convenient/modular harness I could use. Look forward to seeing how the build progresses.

[Guest thefishman65]

Inevo,

 

Where are you located? That is probably way more LEDs than you need unless you are including LED for color matching. Don't for get that solderless has to include wiring prices. Also last time I looked a 12 connector was cheaper than 12 leads (hint cut off one connector). Can you get PMs? I maybe able to help you find some parts cheaper.

[lnevo]

I'm in NY..another DIY thread brought me over to this forum and wanted to see what all you DCers hack up over here

 

I know it sounds like overkill, but it does include colors. The breakdown looks like this

 

28 RB @1000mA

14 NW @1000mA

14 UV @700mA

7 OCW (21 LEDs right there..) @700mA

 

For the OCW combo i would use the red/blue/cyan ones to match the wavelengths.

 

So 28/14 blue/white with everything else as supplemental. Does not seem as overkill now I also wanted a lot of light so it can be used on future upgrades and to make sure my SPS is happy. Also, my canopy is not deep so I can't go high up and I want to have enough coverage, thus more LEDs.

 

RapidLED includes the jumper cable with each diode so really not much more cost. The idea of solder-less along with the makers heatsink really appeals to me if i need to move things/change things around later on.

 

I'm planning 6 drivers (one quad, two doubles and three singles) to drive each color separately. They will be connected to a reefangel PWM module for automation. I like also that the steve's drivers include connection for a dimmer pot so i can have some manual control as well.

 

This isn't anything I'm ready to jump into any time soon...my tank is only 6 months old (with 6 months into the hobby ), so planning this build slowly. Also need the finances to come together for it.

 

I've priced the LEDs/drivers/power supplies and some misc parts at somewhere between $5-600, I dont remember if that included any heatsink or not, maybe a normal one? Not a bad price considering it will be more powerful than 2xRadion Pros and more than half the price

 

My biggest questions at this point are where I'm going to put the components...and how I will mount everything. I didn't mean to hijack the thread so, I'll hand it back to OP to discuss his plans.

[AlanM]

Your setup sounds almost exactly like what I'm trying to build for over my upcoming 75g. Be warned that the UV seem to be a big higher in voltage than the Rebel's, so from what I can see I can only get 6 of them per string if I'm using a 24v power supply, not 7. Also, the OCW chips from LEDGroupbuy are in the mid 8's per star, so you could only get 2 of those, not 3 on one of Steve's 24v channels. You might want to go with only 6 or 8 of those if using Steves, not 7.

 

I was going to use a DIN rail terminal blocks for wiring between power supplies and drivers and maybe end up buying some Meanwell DIN mounted power supplies from store.bravoelectro.com which are more expensive than Steves, but not a ton more, and sure would make it look cleaner.

 

Then from the drivers to the heatsink I'd use Cat6 ethernet patch cables which have 23g conductors and 8 conductors in each cable, so 4 series of 6 or 7 LEDs in each cable. I'd punch them down onto the back of a RJ45 modular jack on a little punch panel attached to the DIN rail and then run patch cables between that and the heatsink. On the heatsink I'd put another small punch panel and wire up the strings onto the back of it with regular 22 or 23G hookup wire.

 

From your config it looks like you'd end up with 10-11 series of LEDs, so that would be 3 Cat6 jacks with a couple of conductors left over to wire up a fan or two on top of the heatsink. I think it would look nice.

 

Also, thefishman65 here has a bunch of experience with this stuff, but I don't. He has lots of really good ideas on his wiki page linked elsewhere. One of them was to put a 5 watt, 1 ohm resistor in each series. Then you can just measure the voltage drop across this resistor while the string is running to know exactly how much current you're running through the string. I'm going to do that for sure. I'll put a two terminal blocks between the drivers and my Cat6 punch panel and put resistors between them so that I can go down the line checking currents.

[lnevo]

The DIN rail concept looks nice...never heard of it before. I wasn't planning on using stars...RapidLED has individual solder-less ones that I wanted to use instead. the idea was to have each color in the OCW on a separate driver. 7 led per string. 11 drivers as you mentioned.

 

I'm still trying to figure it allot and now that you raised the point, I see that each color has its own forward voltage and min/max voltage. This is the part I need to look more closely at.

 

I was going to use Steve's 400 watt supply for all the drivers on one outlet, but I do like the idea of the DIN mounted drivers/power supply. There seem to be a whole slew of them available, which ones were you looking at specifically. I need to make sure they can dim with PWM

 

As far as CAT 5 cabling, this was definitely something I considered, I wasn't sure though if it could handle the voltage though.

[AlanM]

Not Cat5. Cat6. They'd both handle the voltage just fine. We run power over IP from our Cisco routers at 48V and it works just fine. It's the current that you have to worry about. Cat6 uses 23 ga wire which is apparently good to 700ma at least, but it seems like it would do 1000ma if you weren't running it over a long distance. I'd put the drivers and power supply and stuff under the tank, not in the basement. maybe fishman65 can weigh in on this one.

 

I think I'm going to do 3-ups from Steves where you can solder individually and put Cyan/Blue/Red on one chip with no optics. I assumed that you were doing the premade OCW stars from LEDGroupBuy which are all soldered in series.

 

The Red ones are 2V, and the other Rebels are all around 3V, the violet ones seem to be all a bit over 3v, the Cree are all a bit over 3v, but the voltage actually changes a bit depending on the current you're driving them at. The spec sheets are all available online.

 

I hadn't settled on a power supply yet, but it's hard to beat Steve's price for that 400W one. I may give up the opportunity to mount them all on a DIN rail with the wiring to not spend about 3x the price.

[lnevo]

Any updates? How's the build going?

[AlanM]

Was on hold waiting for boards from Itead Studio in Hong Kong, but they arrived today! Took almost 4 weeks to get here since I submitted the Gerber files.

 

They sent 10 of the board I ordered, the one on the right in the attached picture where I'm showing front and back and also 2 free boards, an Arduino Uno and an XBee Pro. Don't think I'll use those, but it's fun to get them.

 

 

From mainland China I got a big bag of terminal blocks, some IC sockets and some tiny SMT resistors to solder up to the board above which will hold the LED drivers.

 

I got a Meanwell SP-320-48 power supply, 48v and 320W, three Meanwell LDD-1000H for 2 Royal Blue and 1 Neutral White strings, and 4 Meanwell LDD-700H for Cyan, Cool Blue, Deep Red, and Violet.

 

I'll need PWM inputs to dim these LDD drivers, so I'm getting a Steve's Aquarium Controller Interface to go between my Apex, which gives 0-10v and the drivers. It translates 0-10v analog into PWM digital.

 

I still don't have LED's or heatsink, but now that I have the parts to power them I'll start buying that stuff. I have my wife on board with the stand arrangement I've settled on, so my build should start moving now.

[lnevo]

Nice!

[AlanM]

I just got a box of parts! My wife said that a "ridiculously huge box" just arrived from LEDGroupBuy.com.

 

I ordered a 36 inch MakersLED heatsink and a bunch of solderless LEDs and 60 degree lenses.

 

30 royal blue XT-E's (452nm),

15 Neutral White XT-E's (4500k),

12 Cool Blue XP-E (475nm),

9 Deep Red 660nm Exotics,

9 Turquiose Exotics (495nm),

6 True Violet Exotics (405nm),

6 Hyper Violet Exotics (430nm).

 

I have all of the other parts except for the controller interface to convert 0-10V from the Apex into PWM for the Meanwell LDD drivers. Stevesleds has a new version of their interface coming out today and shipping tomorrow, so I've ordered those. The nice thing about that is that it has an onboard voltage regulator so you can feed it anything from 5v to 35v, and it will run. I'd like it better if it had a 70v regulator so I could feed it directly from my 48V power supply, but oh well.

 

I'll run 6 channels from the Apex through Steve's aquarium controller interface and have 2 variable ports left over for the two Tunze powerheads.

 

I got the Apex connected last night, updated the firmware to 4.20 for the snazzy new dashboard, got email notifications working and got my no-ip.com name, so I can look at it from anywhere with iPad.

 

Now I just have to build a stand and plumb this tank.

[zygote2k]

that color combo looks like youu're trying to replicate 40k. a little too blue but maybe it'll make your black light posters look cool.

[ctenophore]

Posting this over here since I don't want to clutter up your group buy thread with questions. You said there that you have yours at 2.5 feet off the water.

 

I'd really love to mount mine high like that. I was planning on 12 inches with 40-45 degree optics, but since I've never done it before. I am only just calculating 30inch*tan(20degrees)= 11 inch radius on a 18 inch deep tank 12 inches above the water which will hit the glass, but only by a few inches.

 

Should I really be calculating by the FWHM of the lens or something and assuming that on a 40 degree lens has a FWHM of 20 inches and so 30inch*tan(10degrees) = 5.3 inch radius so lots of shadow around the edges at 12 inches for that lens?

 

I'm getting a rimless tank and I think it will look much better with them that high or higher. The reason I'm getting a rimless tank is that I want to see the contents: critters, rock, sand, and water with as few distractions as possible. Not a big light hanging above or HOB pumps or plumbing drilled into the side or whatever.

 

Maybe I should get 10 degree optics and recess them into the ceiling. 8)

Just now reading through this thread (I'm trying to learn more of the electronics side), but re: intensity spread, don't forget to factor in diffraction from waves/rippes (caustic network). It is thought to play an important role via rapid intensity peaks & valleys influencing photosynthetic output across coral colonies. It should also help blend your spotlights more evenly. So I'd plan to point a water stream at the surface on your new setup. It will look really neat too