Ultimate LED guide

[pbenner]

I used to do surface mount component replacement at my last place of employment. I'll need to get some tools, but I've done it before (The LEDs can't be as bad as the micro resistors we had to do to fix a CPU temperature probe).

 

25 degrees is far too acute to be worthwhile on a 2.5gallon tank, too shallow, right? I assume that I can run them without optics pretty easily, right?

 

As to the CAD design, I've got some friends that use CAD software regularly, I'll see what they can generate for me.

 

Thanks,

 

Paul

[chazde3]

a real CAD program that can export to IGES, STEP, or STL.

Ooo, I has those.

 

My heatsink plans

It shall be epic.

Edited March 5, 2009 by chazde3

[evilc66]

So the opening above my tank will accomodate an 18" wide by 40" long grid of LED's. If I did 6 rows of 20, you think that would work well with the 40 degree optics? Speaking of the optics, closest I found were the Carloc 20mm wide ripple lens to 40 degrees: http://www.ledsupply.com/10211.php

 

Am I missing an optic out there?

 

For power supply, this gentleman out of germany has diy kits with linear regulators for under $3 each, and each can power 6 LED's on 24VDC input. So thinking of getting 20 of those kits, and powering them off multiple 24VDC power supplies: http://www.mpja.com/prodinfo.asp?number=16854+PS

 

Good idea / bad? Thanks again for all your help

 

6 rows sound better, especially with an 18" width. Might wat to still use 24 LEDs on the length. That will get you closer to the 1.5" spacing for the 40 degree optics.

 

Those lenses will work. Cree also makes a 40 degree lens that fits nicely on the LED without adhesives. You can get them from Cutter in Australia.

 

Linear regulators work, but they generate a lot of heat. If they are LM317 (or similar) based, I wouldn't do it. If it's transistor based, then they are much better, and run a lot cooler. Still won't be as good as a true buck converter, but certainly cheaper.

 

 

I used to do surface mount component replacement at my last place of employment. I'll need to get some tools, but I've done it before (The LEDs can't be as bad as the micro resistors we had to do to fix a CPU temperature probe).

 

25 degrees is far too acute to be worthwhile on a 2.5gallon tank, too shallow, right? I assume that I can run them without optics pretty easily, right?

 

As to the CAD design, I've got some friends that use CAD software regularly, I'll see what they can generate for me.

 

Thanks,

 

Paul

 

Sounds like you have a leg up over most people then.

 

There is no need for optics on a 2.5g tank, unless you want some seriously high light levels. Running triple rebels you are already above 70W MH levels. With a lens that tight, you have to run so many LEDs to get coverage, it's not worth it for such a small tank. Plus you would have to run at really low currents to not burn everything (which could be a good thing).

[reef55]

6 rows sound better, especially with an 18" width. Might wat to still use 24 LEDs on the length. That will get you closer to the 1.5" spacing for the 40 degree optics.

 

Those lenses will work. Cree also makes a 40 degree lens that fits nicely on the LED without adhesives. You can get them from Cutter in Australia.

 

Linear regulators work, but they generate a lot of heat. If they are LM317 (or similar) based, I wouldn't do it. If it's transistor based, then they are much better, and run a lot cooler. Still won't be as good as a true buck converter, but certainly cheaper.

 

I'll check out the 40 degree from cutter, see which is more efficient. Thanks

 

Here is a link (in german though) to the guy making the diy led constant current driver kits:

 

http://www.ledstyles.de/ftopic6528.html

 

It uses the Catalyst CAT4101 constant current low-dropout driver as the main component.

 

Another 24 then.. so 144 cree xr-e's with 40 degree lens... yowzer 1:1 white to blue, or 2:1 white to blue ratio (ala aqua illumination)?

 

Any reason why I shouldn't buy the whites from dealextreme (R2, WG bin), seems a lot cheaper than ledsupply or cutter:

 

http://www.dealextreme.com/details.dx/sku.15943

 

Thanks!

[evilc66]

I've seen that driver before. Should work ok, although I'm not convinced they can get 90% efficiency from it.

 

Color ratio is down to you. 1:1 will get you about a heavy 14K look. 2:1 should be in the 12K range.

 

Only complaint I have about any of the LED purchased from DX or KD (other than the shipping delays) is the quality of the pcb and the installation. Not the best IMO.

[lyon76]

hey evil what would you recommend for a jbj 24 gallon setup?

[reef55]

I've seen that driver before. Should work ok, although I'm not convinced they can get 90% efficiency from it.

 

Color ratio is down to you. 1:1 will get you about a heavy 14K look. 2:1 should be in the 12K range.

 

Only complaint I have about any of the LED purchased from DX or KD (other than the shipping delays) is the quality of the pcb and the installation. Not the best IMO.

 

I think if I get 85% efficiency I'll be happy, for the price hard to go wrong since I'll need so many.

 

When buying 72 of them, I'm willing to tolerate cheap circuitboards for $2 less per

[merk1_99]

My 4 gallon is a Finnex. It is a sweet little rimless...Love it, would like another one but I have spent more money on this little 4gal than I did on my 75 gallon reef.

 

 

What type of 4g tank?

 

 

ok when is the next installment of the diy led manual coming....I am anxiously awiating it...

[evilc66]

Thats the tank I have with the LEDs. 10 LEDs is plenty.

 

I hope to have time next week to work on the next section, but no guarantees that it will be finished then.

[erichatesmice]

Evilc, I'm wondering, do the blue LEDs give as much par as an equivalent white LED? I would assume NOT based on other lighting sources. If not, any idea how much you would lose with the blue LED.

 

I am just wondering if it's feasible to run lights with a substantial majority of blue leds to white (i.e.4:1).

[chazde3]

Evilc, I'm wondering, do the blue LEDs give as much par as an equivalent white LED? I would assume NOT based on other lighting sources. If not, any idea how much you would lose with the blue LED.

 

I am just wondering if it's feasible to run lights with a substantial majority of blue leds to white (i.e.4:1).

I'll take a stab at this. The blues aren't going to be anywhere near the par of the whites. As for how much of a difference, I'm not sure. I would guess that there would be quite a difference. As for your 4:1 ratio you may not want that much blue, I would think it would overpower the white. Maybe a 3 blue to 2 white would be a little better. Plus if you use dimmable led drivers you can dial in just the right amount of blue that suits you.

[r3tic]

Actuall I believe I read somewhere that the blue leds had a very high par value, due to the fact that the spectrum range falls right where chloraphyll needs it. Blue just seems dull to us because it is not a color that our eyes are very sensitive to.

 

At a 4:1 ratio you tank would look very atinic.

[evilc66]

r3tics got it. Royal blues produce as much or more PAR than cool whites. I can't say for sure as to if it's more or not because most PAR meters don't measure the blue end of the spectrum very well and report low.

 

When I did tests on my fixture, the royals posted only slightly lower numbers than the whites, mainly because I'm only running them at 700mA versus the 1000mA of the whites.

[pbenner]

So, color aside, it's better to run more blue than white for growth?

 

Interesting, I assume that equal parts royal blue and reg. blue are normal? I could do my 10 gallon with 10 each of white/blue/royal blue in rebels and get 30 LEDs on a 2.5" tank..

 

Hrmmm,

 

Overkill?

 

lol.

 

Paul

[evilc66]

Absolutely no need for 30 LEDs on that size tank, no matter the brand. 10 is more than enough. I prefer royals over regular blues, mainly for fluorescing, and a deeper color tone.

 

With the PAR about equal between royal and cool whites, the balance will be down to what your color temp preference is. 1:1 gets pretty close to a heavy 14K. 2:1 gets a pretty nice 12K, especially with the Rebels. This is what I'm running on one tank.

[chazde3]

Here's one for you evil. What are you're thoughts on runnning the wiring between the heatsink fins. As in drilling holes near each led allowing wiring to pass through. I think it would give a much more clean and professional look to the fixture. I think it would handle the heat, what do you think.

[evilc66]

Thats how I do it. Makes for a much cleaner installation.

[mdavis203]

On a BC14, for example, do you wire your fans to the same power supply that powers the two drivers for the LED's? What does that wiring diagram look like?

[deepdvnarq]

On a BC14, for example, do you wire your fans to the same power supply that powers the two drivers for the LED's? What does that wiring diagram look like?

the bc fans are 12v. if you wire the fans in series, then you can use your power supply to power the fans and the LEDs. you would connect one positve and one negative from each fan and wire those two together. at this point you should have one positive left over on one fan and a negative on the other. those go to the respective leads from the ower supply. i hope i didnt confuse you

[mdavis203]

No, that makes perfect sense. However, in Waterproof's BC14 LED build, he added a third fan to draw heat directly off the heat sink. How would the wiring on this work? You can't wire it in series with the other two on a 24V power supply, I wouldn't think, since this would be a 36V branch of the circuit.

[Lutra]

No, that makes perfect sense. However, in Waterproof's BC14 LED build, he added a third fan to draw heat directly off the heat sink. How would the wiring on this work? You can't wire it in series with the other two on a 24V power supply, I wouldn't think, since this would be a 36V branch of the circuit.

 

You could wire two of the fans in parallel. so you have

 

				  -[Fan]-[power supply]--|		  |---[Fan]--- back to powersupply.				  -[Fan]-

[chazde3]

Allright evil, how's this array look? Total of 39 leds, it would be 20 royal blues and 19 whites. spacing is 2in between each left to right and 2.5in top to bottom. I think I would run it without optics and see if everything likes it and then switch to 60 degree optics if I need to.

 

Edited March 7, 2009 by chazde3

[pbenner]

That rendering is amazing. I can't wait to see this finished. Take pictures as you go, should be a cool project.

 

Best,

 

Paul

[evilc66]

Drop one LED from the center row, and shoft everything over 1" so they are centered between the front and back row. Makes color blending a lot better.

[Dice_cage]

What i would like to know is when taking those number:

12" - ~500PAR

24" - ~200PAR

and compare them with Mh or T-5 what can we expect?

 

 

 

Don't have numbers for a single LED, but I do for an array.

 

Array of 10 LEDs. 4 XR-E Q5s @ 1000mA, 4 XR-E royal blues @700mA, 1 3W UV @ 700mA.

 

12" - ~500PAR

24" - ~200PAR

 

These numbers can vary based on brand of LED and lens, and the drive current used.