Hi everyone!

Firstly I would like to say a big thank you to everybody who has contributed to the mountain of information in these threads!!

I’m in the process of designing/building my reef setup and all things are going well. (Will post pics v soon)

I have many questions to ask so I will start with the more important ones first..

The main tank has seemingly odd dimensions compared to most of the tanks I have seen while reading through NR forums. 150x45x45cm (59x17x17")

The hood will contain 3 home made heat sinks 45x40cm (17x15")

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And I am at the stage where I need to find the best layout/number of LED's per HS.

Click to view attachment

The drawing may be a little rough but you get the idea..

The X represents diodes and will be alternating Cree XR-E(13) cool white and RBlues(13) driven at 1000mA
Are the spacing’s going to be sufficient? (L to R, F to B)
I am planning on using optics but I’m unsure if 60deg or 40 would suit this schematic? keeping in mind the tank will probably be 15-16" to the sand bed.

I can also mount the hood at any height from the tank to possibly help reduce the spotlighting that i think this setup may give.

I would appreciate any help or advice


Paul

They look fine provided you can live without dimming and live in a country that uses 220VAC (don't know where you live).

The problem with running in parallel is if an LED in one string fails, it creates an imballance. If the LED fails closed (a short), the side that had that LED is now being driven at a higher voltage and can cause more failures. If the LED fails open (takes out the entire string), then the other string assumes all the current, instead of half. If running a 1000mA Buckpuck and Cree XR-E LEDs, that's not such a big deal provided that the heatsink can handle the heat.


K2 royals are pretty bright. Using Crees for both gets a pretty good 14K look IMO with a 1:1 mix. It just makes it much easier to blend the colors and not get odd colored shadows. Just use the drivers to adjust the color temp after it's all set up.

20 LEDs per row is better. At 2" spacing, it's 38" from end to end, leaving 7" from the glass on each end. 22 LEDs would reduce that to 5". Depending on what you want your overall light levels to be, 60 degree lenses should be fine. They will be better suited for a mixed reef. 40 degree options will be better for a heavy sps setup.

i am replacing 2x250W MH and 2x54W T5, primarily going for SPS so i will stick with the 40 degree.
1:1mix, 6 rows of 20 leds, to the edge of the heatsink, giving close to 2,06" spacing.

Should i go for 1A buck for all, i see some others only usig the 700mA for the blues?

thanks

Go 1000mA across the board. Your heatsink should be plenty adequate to keep die temps down so life isn't shortened.

I am thinking of putting together a small LED light and I would like to know if this power supply is enough for the LED's and the fan.
This is from Jameco electronics (Jameco.com).
Model # 252833 PWR SPLY,SW,WALL,12V/1.25A,15W,2.1x5.5mm,F2,UL/CUL/CEC.
The lighting will consist of 3 Cree LED , 1 white and 2 royal blue.One Buck puck w/pot @ 1000ma.
A CPU heatsink and fan will be used for cooling.
Not looking for future upgrading with this system and I only want what is needed without going overboard on spending , money is tight right now.
Wiring is a bit sketchy for me and I remember reading something for a 12v PSU and wire in "parallel".
I will most likely tap the heatsink to mount the LED's with screws , though is it possible to just use thermal epoxy?

A power supply like that will work fine with jsut 3 LEDs. Check out MPJA though as I guarantee that you will find an equivalent power supply for less.

Thermal epoxy can work, but you must apply pressure as it cures for it to be really effective.

Thanks for looking into it though would you know if the fan can run off the same PSU?
It will be a CPU fan so I am thinking it is the usual 12v kind.That said it makes sense to
me that it "could" because the PSU is 12v but I wonder if it will take too much away for the
LED's.
Also what is your opinion on wiring for the 3 LED's with a 12v PSU?
I'll check out MPJA for alternatives.
Thanks.

The voltage is fine, but you need to make sure that the power supply you pick has enough current capacity to run the fan. Most PC fans run in the 150-200mA range, and that power supply will work. Check the fan you are buying though to make sure. When in doubt though, get a bigger power supply.

Honestly, I'd use one of these. It's half the price of the Jameco unit and has a 2A capacity that will remove any doubt that it will handle the LEDs and the fan. Plus, with the "desktop" style power supply, you get extra cord length.

Cool , thanks for the info.

yeah dimiming is not a problem.. and i live in Australia.. im pretty sure its 240VAC, so do i just cut any random power cord and hook it up to that bad boy.. sounds easy enough to me..

thanks for your wealth of knowledge.. once i get all my bits together ill be sure to start up a thread and step by step how i go..

Evilc66 I was wondering if you has a chance to look at my lighting schematic and give me any ideas??

tank size 150x45x45cm (59x17x17")

hood comprised of 3 heatsinks measuring 45x40cm (17x15")

Click to view attachment

The drawing may be a little rough but you get the idea..

The X represents diodes and will be alternating Cree XR-E(13) cool white and RBlues(13) driven at 1000mA
Are the spacing’s going to be sufficient? (L to R, F to B)
I am planning on using optics but I’m unsure if 60deg or 40 would suit this spacings between LED's? keeping in mind the tank will probably be 15-16" to the sand bed.

I can also mount the hood at any height from the tank to possibly help reduce the spotlighting that i think this setup may give.

Your spacing is a little wide if you want to use optics, but considering the depth of your tank, you may not need to. Some of it will really depend on what you are looking to keep. If it's going to be a mixed tank with primarilly lps and softies, and sps at the top of the tank, you are fine as is. If you want a little bump in performance, 80 degree lenses should work with that spacing. If you are looking for higher light and want to go to a 60 degree lens, you are going to have to tighten up the spacing to about 2" per LED in each row, and about 2.5-3" per row.

Thanks for the super quick reply!

Can the 80deg optics be ordered from ETG? i was hoping to get most things from there unless you know of somewhere closer to Australia???

Also I was wondering about the meanwells.. i will post a question in that thread for you mate

Paul

60 is a better lens

You have one of the best places right in your back yard. http://www.cutter.com.au

Hi Sherman, thanks for the advice, earlier in the thread i recall someone recommended 40 degree for 24" depth? is 60 still good enough for SPS at 24"

Thanks to all for this great thread and the advices given.

Dennis

If you are going full sps all the way down to the sand, 40's will work. If it's going to be more of a mixed setup, the 60's will be a better choice.

Not to get off on a side topic, but a couple things I've learned with my fixed lighting projects that Evil might want to include.

First thing is I've pretty much ditched Cree white tints when I need +1000 lux values, and instead switched to Bridgelux. The big Bridgelux arrays are simply cheaper per lumen dollar (in the USA) even though they aren't as efficient as Cree. For instance, their 2000 lumen cool white monster costs me $40 (driven at stock / hint hint), and that's a lot of light for the money. I also prefer to work with fewer, brighter LEDs and have fewer light sources. However, optics for the Bridgelux are hard to come by. However, if you need a bare emitter with absurd intensity values these puppies make an over-driven R2 look dim.

This will likely change though once the XP-G hits the market - depending on cost.

Another tip is I make my own thermal epoxy. The commercial stuff is too expensive, and contains trivial amounts of silver (less than 5%). You can make your own with any type of regular epoxy and mixing generous amounts of aluminum powder in with it. Alu powder is used for both fireworks and a paint additive, and can be found online for about $15 a pound (more than you'll ever need).

Thanks for the input, and it's certainly not off topic.

The Bridgelux LEDs are certainly an option, but we have found over time that single point sources don't illuminate as well as multiples spread across the tank. This is one reason that we aren't using MC-Es and P7s. Plus, you can't get blues in the same power level.

Evilc66,

i see in the groupbuy that you ordered the WG bin of the Q5, is there a big difference compared to WC, WD or WF?
I am setting up a small groupbuy in Denmark, from ETG, just wan't to make sure i order the correct ones.

is it enough to specify XREWHT-L1-0000-00D02?

Thanks.

WG bins are the most common that ETG stocks, and also has the highest yield from Cree. Higher temp bins tend to look a little more washed out. I like the warmer tones of the WGs personally.

Thanks again Evilc66, you rule ;o) I will go for the WG.

Dennis

I just saw evanski's pico led fixture (comprehensive....)and it is similar to what I am building.From the parts list evanski is using just a 12v 3ma power supply to run the LEDs and the cpu fan?
evanski is using 4 leds and two drivers where as I will be using 3 leds and one driver @1000ma.What I don't get is how that fixture is powering the fan , drivers and leds off of just 12v-3ma.Granted the 3ma current is fine but the 12v is where I am puzzled.I read the specs on the buck puck and cree leds and to run 3 leds @ 3.7-1000ma , a buck puck 2-5v-20ma you would need a 15v 1000ma power supply , at least.That is also minus the
fan which in my case will run 12v-.76ma.Is evanski's fixture running at its full potential?Does not seem that way to me unless my math is wrong.
Well my parts list goes like this:
1 cree white
2 cree royal blue
3 cree 40 degree optics
1 buck puck @1000ma
1 cpu heatsink w/fan 12v-.76ma
1 15v-1000ma power supply for the driver and leds
1 12v-200ma power supply for the fan
Still waiting on the power supplies , they should arrive by the middle of the week so I haven't put anything together yet.I need some more insight so I can get it right the first time.

Running at 700mA max should be enough depending on the size of your tank and your livestock. From the sounds of your setup, it's going to be a small tank.

At 700mA, the LEDs run at a max voltage of 3.5v. After the ~2v for the Buckpuck, you are at ~12.5v (worst case), and typically still within the tolerance of a 12v power supply. Using a 12v supply will let you use it for the fan without having to resort to a seperate unit.

I figured as such that the unit wasn't running at full , at least for the 1000ma driver.My tank is a 2.5 aga and as for livestock , it will build up along the way.Well with the 15v-1000ma power supply I can run the leds at full and from what I have been reading here it makes some difference.The blues may not benefit from the 1000ma but it will be there if it does?Since the fan is a 12v I picked up a different power supply as to not burn it out.Don't think an extra 3v would kill it if I ran it on the 15v but that supply does not have the extra current.I read you can mess up your supplies if there is more demand than they can handle.I got them at a good price under $20.00 minus shipping though
Thanks again evil.

Considering this is for a 2.5g AGA, why the 40 degree optics?

Well its not set stone , I had a hard time finding anything else.I bought from ledsupply.com and they appear decent enough compared to the other optics they sell.What would you recommend and from where?
I remember reading here that the 40's can give a high par , at certain distances.I am considering making the fixture pendant style to adjust the height.I figure this will help spread the light some and not burn my coral too.

You would have to hang the fixture 3' above the tank to get the PAR levels reasonable. For a tank that size, ditch the optics and run the fixture about 4" above the water. You will get better spread and still good PAR. 5 LEDs isn't a lot for a tank that size. My normal recommendation is at least 8.

That's a good one.O.K I will experiment and see what happens.

I want to make a LED-light for my 14G reef-tank

I found these lights and equipment but do I forget something
and are these lights good enough for a reef-tank.
And how many lights do i need?
5 white and 5 blue lights????

Tkanks!!

Luxeon star white
Luminous Intensity typ. (with 10° collimating optics): 500.000mcd
Power Dissapation: 1W
Luminous Flux (typ.): 45 lm
Viewing Angle: 140°
Color Temperature (typ.): 5500K
Forward Voltage: 3,42V
LED Current (If): 350mA

Luxeon star royal blue
Luminous Intensity typ. (with 10° collimating optics): 120.000mcd
Power Dissapation: 1W
Radiometric Power (typ.): 150mW
Viewing Angle: 110°
Wavelength (peak): 455nm
Forward Voltage: 3,42V
LED Current (If): 350mA

Dimm Driver
Technical Data:
Input Voltage: 230 - 240 V
2 outputs á 350 mA
10 Watt power per output = 20 Watt power overall
Connection for dimmer 0 to 12 V

Universal power supply 9-24Volt / max. 1500mA - regulated

Heatsink

The LEDs are on the low end of the scale in terms of performance. There are much better options available, even if you only want to run at 350mA.

Could you please share some details on what you are planning to light with this?

zoas and maybe sps and lps

are these better?

Cree XR-E Q5 Emitter
Technical Specifications from Datasheet:
Power Dissapation: 1,23W
Luminous Flux (min./max.): 107 lm / 228 lm
Viewing Angle: 90°
Color Temperature (typ.): approx. 6000K
Forward Voltage: 3,7V at 1000mA
LED Current (If): max. 1000mA

luxeon star 3w rank T
Technical Specifications from Datasheet:
Luminous Intensity typ. (with 10° optics): 800.000mcd
Power Dissapation: 3W
Luminous Flux (min.): 67,2 lm (700mA)
Luminous Flux (max.): 87,4 lm (700mA)
Viewing Angle: 140°
Color Temperature (typ.): 5500K
Forward Voltage: 3,7V (700mA), 3,9V (1000mA)
LED Current (If): 700mA/1000mA

Cree MC-E
Technical Data
Viewing angle: 110°
Color of light: white
Colortemperature (typ.): 5000K to 10000K
CRI: 75
Housing: waterclear
Measurement: L x B x H: 7,50 x 7,00 x 4,48 mm
Thermal resistance: 3°C/W
Luminous flux by connecting all 4 chips in series:
min. 370 lm at 350mA
max. 650 lm at 700mA
Data per Chip:
Current (If): 350 mA to 700mA
Forward voltage typ.: 3,2V at 350mA - 3,4V at 700mA

2x18 cree q5 and royal Blues should be enough to grow sps over a 86l. tank right? 70x35x35 cm

Better. I would stick with the same brand and series LEDs for the entire project though. We typically prefer Cree XR-Es here, but Luxeon K2's and Rebels work also. I wouldn't bother with the MC-E. It's too bright for most applications and makes it difficult to work with blue LEDs to get the right color temp.

What are your tank dimensions?

The tank is 40x40x30 cm
(14x14x11 inch)

Plenty


10 LEDs won't cover the tank very well. 15 would be better in a 5x3 arrangement. 20 LEDs in a 5x4 arrangement would be even better.

Oké i will get 10 white and 10 royal blue Cree 5q

Thanks so far!!

how is the growth on sps under leds? can't seem to find any good sources. but maybe I haven't looked hard enough.

Can some help me out with a question / problems I am having with my LEDs. I built a fixture for my 10 gallon nano. I used 12 CREE XRE (6 white and 6 RB) along with 2 buckpucks (One to drive the White and one for the Blues) The Buckpuck are the 1000 mA with the 32 max V. I am using a 30V 1A converter to power the buckpucks. The problem I am having is that the buckpuck stop working on me (have happened to me twice about 3 months apart). I have gone through 4 of them already. Everything looks like it should work without a problem but every couple of months the buckpuck fry.

Any one have idea of why this is happening and what can be done to fix it?

Thanks
Brad

30v 1a is too little current to power a 1a buckpuck on full power. I'd start off by getting a new power supply (2x >24v >1.2a or 1x >24v >2.4a).

Did you keep the buckpucks in an enclosed area? How far are the bucks from the leds?

Ok, I've got all my parts now and finally have gotten some time to work on a light for the sh tank.

I managed to get 104 holes (2 per led but I left the brace area unlit). drilled and tapped this weekend (only took 3 different trips out to buy bits/taps).

I've got a few pictures and will try to get some at each stage for a build thread.

But first 2 quick questions?

1: Do I need thermal compound? For a cpu I wouldn't consider not using it, but most other stuff (voltage regulators mostly) I usually just screw it tight.

2: Can I use nylon screws or will it get too hot and deform causing the leds to lose good thermal contact?

The buckpuck are in a project box about 3' away from the LED. I am actually running 2 converters, one for each buckpuck.

Here is the wiring diagram.

30v seems like an odd voltage. Is it AC or DC output? Also, what model Buckpucks are you running?


1. I would suggest it. The cooler you keep the LEDs, the longer they last.

2.The issue isn't that they will deform, but more that they can't apply the correct clamping pressure. I would use stainless screws with nylon washers.

Here is the link to the Buckpuck and Adapter I am using.

http://ledsupply.com/03023-d-e-1000p.php

http://www.radioshack.com/product/index.js...oductId=2049692

Just wanted to check. There have been some people that have accidentally ordered the AC version, or accidentally powered the DC version with AC supplies.

I would check the output voltage of that supply when it's connected. Linear power supplies can many times run at a higher voltage than they are supposed to. 30v is pushing the limit, and if the power supply is out of tolerance, you could be hitting 32v+ which could damage the driver.

I will check when I get home, what adapter would you recomend I use for my set up. I think radio shack may just be cheap and would rather spend the money to get something more reliable then to just keep on replacing buckpucks.

Radioshack is actually really expensive. There are many good 24v supplies available that will be a lot cheaper and will run your array just fine (you need a minimum of 24v). MPJA has a good selection of power supplies.

hey evil, what is the difference between a regulated PSand a constant current driver??? what stops me from running 3 parallel strings of 4 with a regulated PS of 12vdc and 2.5 amps

or something along those lines.

A regulated power supply regulates voltage, while a constant current source like an LED driver regulates, well, current LEDs are current driven devices and have to have the current regulated very closely for them to operate properly. The driver changes the output voltage to whatever the LEDs require.

After reading your guide I have decided to build an LED system for a 20g (12"X24"X14") I am starting to set up. I am thinking of 12 CREE Royal Blue and 11 CREE Cool White in an 8,7,8 pattern. My question is will 2.25" spacing between the LEDs with 3" between the rows work ok with 60degree optics?