DIY LEDs - The write-up

[der_wille_zur_macht]

Wire them to a driver (you can do lots at once if you want). Run them at your target current. Read voltage across each one with a multimeter, by probing right at that LED's solder pads.

Really, the only trick to it is not blinding yourself. It helps if you have optics or an optic holder that leaves the pads exposed, because then you can easily look at the LED from the side without getting blinded.

 

[DustinB]

First off I apologize if this info was stated somewhere in this thread. I've read a good bit of it but I don't have a month to go through all 137 pages.

I have a 90 gallon oceanic tank(48x18x24). I'm currently running 4x65w PC's. I will be upgrading my lighting before long and I want something more powerful than T5. I was looking at a MH setup but for the money and heat I was considering doing an LED setup, plus it would give me a chance to finally use my new $250 soldering iron.

From what I picked up on the thread and others I take it you basically need 24 LEDs per 2' of tank. I'm planning on making one fixture to go across the whole 4', possibly 2 fixtures. Basically I'm wondering how many LEDs I will need for this tank and what kind of setup? Which reflector angles? I hang the fixture from the ceiling if necessary, but how how above the tank for which recommended setup? I'm guessing 12+ inches would be great to cut down on heat from the light.

Any input would be great. Looking forward to setting up my own build thread.

 

[uireef]

My light is almost complete now I just need to add fans. I have 4x48" heatsinks. I'm putting an acrylic shield about an inche off the bottom of the heatsink. Think three fans blowing on top of the hsinks will work?

 

[der_wille_zur_macht]

From what I picked up on the thread and others I take it you basically need 24 LEDs per 2' of tank. I'm planning on making one fixture to go across the whole 4', possibly 2 fixtures. Basically I'm wondering how many LEDs I will need for this tank and what kind of setup? Which reflector angles? I hang the fixture from the ceiling if necessary, but how how above the tank for which recommended setup? I'm guessing 12+ inches would be great to cut down on heat from the light.

Any input would be great. Looking forward to setting up my own build thread.

24 LEDs per 2' of tank would depend on the width and depth of the tank. You can probably approximate a typical 250w MH in both spread and intensity with 20 - 30 LEDs, medium-wide optics, mounted around a foot off the water.

Another way to think of it - calculate the square inches of surface you have to cover (864 in your case). Then, figure 10 - 20 square inches per LED. For you, this puts you in the range of 50 - 80 LEDs, more or less.

Of course, it depends on which LEDs you get, drive currents, optics, spacing, etc. Plus, the obvious factor of how much light you actually want in the tank (i.e. SPS, fish only, etc.)

My light is almost complete now I just need to add fans. I have 4x48" heatsinks. I'm putting an acrylic shield about an inche off the bottom of the heatsink. Think three fans blowing on top of the hsinks will work?

It's super tough to exactly figure cooling requirements without a degree in thermal dynamics and a lot more info than you've posted. The good news is you can always just run it and see. It sounds like you'll be in the right ballpark.

 

[MikePetro]

So, are you guys all really using 4-8 drivers to power your rigs? Arent there any other solutions out there? At 60 LEDS I need 3 strings of ~70vdc. The highest voltage I am seeing is in the mid 50s, is this because of rectifiers converting the AC, ie half of 120ac? Are there other solutions, perhaps using DC Power supplies with a constant current regulator using something like a LM317 or LM2576 ?

http://www.national.com/pf/LM/LM3404HV.html#Overview

Also, do any of the Meanwells have a SVR2 adjustment of more than -25%?

 

[Reef_Matrix29]

I'm using 4 meanwells to drive 48 LEDs on 4 strings. I find having more strings/drivers makes it easier for me to tailor my light intensity needs front/back and side to side a lot better than just a few drivers and all or nothing type of control.

 

[Neogenocide]

Thought I would share what is close to my final results with my build. I finally got my lights elevated to the height close to where they will stay. There are 17 LED's per half, 34 LED's total. 18 Blue, 16 White XR-E. 60 degree optics, about 8 inches off the water. Using the fixed current 700watt Meanwell drivers. Sorry about the cloudy water, but I just cleaned the glass and still up the sand a bit. The pics don't really do it justice, they look much better in person. I'm blaming the cheap camera

Scott

 

[Gomer]

I don't want to go through all 138 pages ....

So...Anyone find any economical solutions to the 420 to 400 nm range?

 

[widmer]

Not that I'm aware of.. We're fixated on the Cree LEDs only, and they don't come in that flavor

 

[pheinzig]

WOW! Ive been following LED's for a few months. I stumbled across this thread a while ago...back when Soundwave first started it, I had it saved for future reading.
The other day I started from the OP, and read in detail the first 30 pages, thinking Id have my questions answered, most of them yes. But when I skimmed ahead to see how long this went, I got demoralized

WOW WOW WOW!
this is the longest thread EVER!
Its going to take me at least a week to absorb all the concepts attached to this topic. I do have some comments/questions. If they have been answered already, sorry. Normally I'm one to read the thread first, rather than wasting someone else's time when I can answer it myself.
But obviously...it will not only take a while, its quite possible that it will be missed(hours of reading is boring). So with that in mind, please forgive me.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Just a rough outline of the parts i plan to order to get my LED array started.
I went to a major LED supplier that seems to be popular with the LED community, they had "Bundles" so I put a few together. Are these bundles garbage? should I just try to order the individual parts instead. I dont mind paying extra. You get what you pay for.
http://us-dc2-order.store.yahoo.net/...onId=ysco.cart
* LED Type : Cree XR-E
* # of LEDs : 18 (+$119.00)
* Color : Neutral-White
* Drive Current : 1000mA
* BuckPuck Options : Dimming w/ Pot. (+$4.00)
* Power-Supply : 24vdc1.7a (+$21.99)
At $181.94, ill order three of these.
Color choice for white was debatable. They offer Cool white,neutral white, and warm white. I dont know which would be best. So i went with Neutral. I dont understand what w/pot means. I assume poton pack, ive heard the word a couple times. I have no idea what it means(or if they are even needed). So an explanation would be nice). But at an extra $4, im not worried(unless its something I DONT want incorporated).

For the blue, same thing pretty much:
* LED Type : Cree XR-E
* # of LEDs : 18 (+$119.00)
* Color : Royal-Blue
* Drive Current : 1000mA
* BuckPuck Options : Dimming w/ Pot. (+$4.00)
* Power-Supply : 24vdc2.5a (+$29.99)
At $189.94 each, Ill get three.

The grand total is just over $1,100. Ill still need the Cooling fins,alum frame, thermal paste, and a few other odds and ends.(picking them out will be easy), and relatively cheap compared to everything else.

Total will be 54w/54b. Ill divide them amongst 2 panels, left and right. Aprox 32" in length each. Ill build a custom canopy, and am hoping to make something that allows me to raise/lower the array to allow me room to work inside the tank when I need too.(Like sticking my head over the water from time to time)
What I'm hoping to achieve is a quality DIY LED system, that rivals something I would have to pay 3x as much for to have solaris make. And theoretically, something Ill be much happier with. Also Dimming Is an absolute MUST! I want to independently control the lighting so make my own custom color schemes(as well as tune it down a bit, if im over burning the corals).

Now aside from the Color choice in white, and the "Whats a poton pack added for?".
I do have a few others:
I was going to order the 1000ma kit( does this mean the bulbs are rated at 1000ma?)
Or is the driver 1000ma, and all Cre-XRE bulbs are 1000ma anyways?

I was wanting to have this system running at 700ma, but bulbs capable of 1000ma lit by it.
My reasoning is that running the bulbs roughly 30% under max would improve the life of the bulb.
Ive read this from several sources, that you want to run them at less than max capacity, and it makes sense.. so I want to do it.

And finally, optics. Will I need to be getting optics with this many LED's? The tank is a standard 125g Brick. I think 22" deep(so realistically the light would only be penetrating 18" of depth at the most)

 

[TheFishMan65]

pheinzig,

I bet there is another post before I finish typing.

I would go with cool white. Most here seem to think that is best.

First the pot for the buckpucks allows for dimming. So you want them. This will allow the 1000ma max current pucks to drive at 700ma (or other) if you want.

Those power supplies are an issue. You list 1.7 amp and 2.5 amp, but neither will drive 3 buckpucks at 3 amps. Also if they are not corrected for power factor you may have an issue with them drawing too much current at power up and popping circuit breakers.

Also the recommendation is 1 LED per 10-20 square inches of water. So depending on what you have you maybe able to lower it some. Your currently right in the middle so that is good.

[EDIT]
I lost. I don't believe it! A whole half hour and DWZM didn't beat me. Maybe he is stuck under his tank

 

[pheinzig]

Those power supplies are an issue. You list 1.7 amp and 2.5 amp, but neither will drive 3 buckpucks at 3 amps. Also if they are not corrected for power factor you may have an issue with them drawing too much current at power up and popping circuit breakers.

Also the recommendation is 1 LED per 10-20 square inches of water. So depending on what you have you maybe able to lower it some. Your currently right in the middle so that is good.

[EDIT]
I lost. I don't believe it! A whole half hour and DWZM didn't beat me. Maybe he is stuck under his tank

THX for the recommendation on 10-20 inchs. I calculate I come out at around 1 LED per 12inches. Nice to know I got it right! ThX.

Moving on, cool white it is, TY.
As for powersupply:
I pretty much just stabbed at it. The "Kits" only gave you a few choices.
I chose the two that made the most sense to me, not knowing what the difference was. Im starting to think, It might be better to just order the parts separately, Ill pay more. But I think Ill be happier in the long run. Considering this....

I am pretty sure Ill get the Cree Q5 XR-E series in cool white(a little more expensive, but if I understand correctly, its the best Cree offers).
cut/paste quick specs:
# White Cree Q5 XR-E Star Features: 107 lm @ 350mA
# 1000mA - Max Drive Current
# 3.3Vf - Typ. Forward Voltage @ 350mA
# 6500K - Color Temperature
Ill order a few extra, just in case. Ill get 60 of these, with the intent to wire in 54. I don't know what line 3 means. "Foreward voltage at 350ma", but I get line 1/2/4.

Also Ill get 60:
# Royal Blue Cree® XR-E Star Features: 425mW Flux @ 350mA
# 1000mA - Max Drive Current
# 3.3Vf - Typ. Forward Voltage @ 350mA
# 450nm - Wavelength
Again with the intent to wire in 54. And obviously... line #3=huh?
Line 4 I assume means they are around 20k spectrum. Correct me if Im wrong. But I think that's the whole point people choose these royal blues. they make the colors really POP!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Sooooo... using these bulbs as my foundation to start with, and knowing I want to have a dimmable feature. Would it be too much trouble to request some help choosing the remaining drivers/power supplies ect? I dont want to sound lazy. I jsut really am having some trouble absorbing it all, and dont want to mess this up. Id like to nail it on the first attempt, and I know you people are the ones to consult. Lets keep it under $1,500 pls

My dad offered to help me, but hes "Busy" and wont read through the hundreds of pages...I don't blame him. However,I am completely confidant that if I present him with a parts list and a few screen shots of what Im aiming for, hell be able to help me with the rest(I.E. Soldering/wiring ect).
He has an understanding of this sort of stuff(used to work for boeing doing the wiring and what not on aircraft. Also builds ham radios as a hobby. So Im not worried that final assembly will pose any trouble.


PS, is it possible to have these all(54W/54B) on just two power supplies, and 2 dimmers? IE one for white, one for blue. Simplified controls would be nice!

 

[TheFishMan65]

Line three means that at 350 ma the forward voltage is on average 3.3 volts. Run them at a lower current they will be dimmer at the forward voltage will go down. Run them at a higher current and the will be brighter with a higher forward voltage.

Power supply it looks like you will have 18 strings of 6 LEDs each. 6 x 3.3 is about 20 volts you will probably run them a little brighter so that is why a 24 volt power supply is needed. Since each string need up to 1 amp the supply must be capable of supplying 18 amps. Usually you want a little extra so say 20 amps. Or two at 10. Or 4 at 5. etc. The problem is that they have an inrush current when first turned on so they can pop a circuit breaker.

Not great with buck pucks, but you should be able to hook all 9 up to on pot for dimming (or one PWM) for each color.

 

[FW fugitive]

I don't want to go through all 138 pages ....

So...Anyone find any economical solutions to the 420 to 400 nm range?

Depends on what you mean by economical. Ledengin (stocked by Mouser) has 5 & 10W 400nm LED's on stars - the 5W versions are $30 per. I'm thinking of using 3 of them in a build for a freshwater planted tank. This wavelength induces anthocyanin formation in plants (red leaf color).

 

[skippyreef]

I ordered my 400nm ledgin from mouser electronics and the service was great.

 

[Obi-dad]

There was an study a while back that showed that the only things produced in corals in response to UV wavelengths were clear protective proteins, not pigments.

What I would like to see are the 420nm LEDs (purple, the original 'actinic' color - most people today say actinic when they are talking about blue, or 450nm light, but the original actinic bulbs were purple).

 

[joseney21]

pheinzig i would recommend you read the last 30-40 pages of this thread....you can also read taqpols thread, it's only a few pages long

 

[pheinzig]

pheinzig i would recommend you read the last 30-40 pages of this thread....you can also read taqpols thread, it's only a few pages long

THX,
like I said, I got about 30 pages into it, and got demoralized. I know Ill still have to read them all eventually.
But at last count it was: 40+40+138! Thats gonna take me a while to digest.

Knowing I can concentrate on the last 40 of this one will be a big help!

 

[Jay1982]

I read page 1 to 118 and took notes on a Word doc if you want the notes on it. But I only took notes on things that applied to me. After page 118 I was up to date so I didn't take any notes from there on out

 

[Jay1982]

So I was in a computer parts store today and they had a bunch of wire, so I picked up some 24 gauge wire. I'm wondering if its ok to use from LED to LED. There is a picture below. On the side of the wire it states: 105 degree Celsius, 600 volts (and has this writing on the side) FT-1 AWM E107863 STYLE 1015. Does this mean anything? And is it good to use? I cut a bit of the wire off and it seems like it has four or five thin metallic wires. I asked the store rep if this was tinned or not and he shrugged his shoulders.