Easy step-by-step LED build

[yupgopotty]

I’ve been following various LED threads here and on a few other forums (ie. Nanoreef) for a few months now and have done quite a bit of research. Last week I finally pulled the trigger and decided to join the world of DIY Aquarium LED lighting.

I ordered my equipment from rapidled.com. They had a kit available which I purchased and built (the 24 LED one). I also ordered a 12” x 8.5” heatsink from heatsinkusa.com.

This kit build differs from Shockwave’s (http://reefcentral.com/forums/showthread.php?s=&threadid=1587273) in a few ways:

1) No buckpucks
2) Because there are no buckpucks, no AC DC power supply is necessary. I figured this would save me from the extra wiring inherent in that kind of setup and $30-$40 that I would have spent on the AC DC power supply.
3) I used the lenses that came with the kit.

I liked this kit based on the fact that it required far less wiring.

Shockwave’s build goes from:
Outlet -> AC-DC power supply -> Buckpucks (8) -> LEDs

Mine goes:
Outlet -> Drivers (4 for a comparable number of LEDs) -> LEDs


Pre-build

The Kit Included:

-12 Cool White CREE XR-E LEDs (XREWHT-L1-0000-00C01)
-12 Royal Blue CREE XR-E LEDs (XREROY-L1-0000-00A01)
-2 x 700mA Constant Current Drivers (Mean Well LPC-35-700)
-24 Lenses (40 degree)
-1 set of Arctic Alumina Thermal Epoxy
-2 power cords
-4 wire nuts

Because the kit included most of the parts I required, I only needed the following additional tools:

Soldering Iron & Solder
Wire for wiring the LEDs to each other (anywhere from 16-22 gauge should work fine)
Wire Strippers
Beer

From what I’ve researched, these specific CREE LEDs can handle up to 1000mA (1A), however I did not feel driving them at their maximum was a wise decision. As we know, the more power we put into the LED, the less light it outputs per extra mA of input – we get diminishing returns. I could not locate any information that the LED manufacturers: CREE, Seoul and Luxeon, recommend driving their LEDs over 700mA, although this may change. I decided that to achieve consistent lumen output and color maintenance over the life of the LEDs, which I hope, will be 10 years, that I would err on the side of running them conservatively.

To further add to my decision to not run my LEDs at 1A, PFO on their Solaris light, in its most recent revision, went from driving its 24 LEDs at 1A (1000mA) in each array to 30 LEDs at 800mA. I do not think that it is a mistake that PFO decided to run its LEDs at lower amperage. As such, I will be running my LEDs this way also. Lower amperage should translate to longer life, lumen maintenance, and reliability.

Here is a mockup of how I arranged my LEDs. I simply alternated blue and white LEDs all the way across.

http://reefcentral.com/gallery/data/500/213612pic_1.jpg


Spacing

Since the heatsink is 12” long by 8.5” wide, I figured spacing 1” between LEDs and about 1”-1.25” from the edges would be ideal. Each LED/PCB takes up about 0.8”, so there isn’t much room even if I wanted them spaced further apart.


Cutting, Stripping, and Tinning

After lining up the LEDs you’ll need to cut (n-1) pieces of wire to connect all the LEDs, where n = number of LEDs. It was a HUGE pain for me to strip wire without any wire strippers. I had to quit after a few wires and run down to Radio Shack to get proper wire strippers ($5). Trust me, your hands and fingers will thank you if you get the proper equipment!

Once you have the wire stripped, it’s best to “tin” the wire by putting solder on the ends so that the wires will solder onto the LEDs much easier. The LED star PCBs absorbed a TON of heat from my soldering iron, so tinning made soldering the LEDs together much easier.

http://reefcentral.com/gallery/data/500/213612pic_2.jpg


Soldering

The wiring scheme for each of these drivers is ‘1 string in series,’ i.e. 1 string of LEDs all in a line. A series circuit is wired + to – throughout the string. Each LED has solder pads that are clearly labeled “+” or “-“. Each LED will have one wire coming in (either + or -), and one wire leaving (which will be the OPPOSITE polarity of the incoming wire. Incoming + means outgoing – and vice versa). If you arrange the LEDs correctly, you can have a nice string without having to criss-cross wires.

http://reefcentral.com/gallery/data/500/213612pic_3-med.jpg

The drivers run 1 string of 12-13 LEDs each, so I’ll have a total of 2 strings. Both will look just like the one above.

The final step in finishing off the string would be to attach the driver. Each driver comes with a positive and negative wire so just attach the + wire to a + solder pad on the pcb (keep in mind what we mentioned earlier: “incoming + means outgoing – and vice versa”. Just treat the driver as if it were another LED), and the – wire to a – solder pad.

http://reefcentral.com/gallery/data/500/213612pic_4.jpg


Splicing

You will need to splice the remaining wires from the driver to the power cord. Here you have an option. You can either use one power cord per string (12 LEDs), or you can use one power cord for both strings (24 LEDs).

The driver I used had wires labeled ACN and ACL. I spliced the ACN wire to the white wire from the power cord, and the ACL wire to the black wire from the power cord. I twisted the wires from the drivers and the power cord together and held them using the included wire nuts. They were gel filled, which should keep any water out.

If you want to drive both strings (all 24 LEDs) with one power cord, simply twist both ACN wires from the two drivers together along with the corresponding wire from the power cord (in my case, the white wire) before putting them into the wire nut. Repeat the same process for the ACL wires from the drivers and the corresponding wire from the power cord (in my case, the black wire).

http://reefcentral.com/gallery/data/500/213612pic_5.jpg

If done correctly, this is what should happen:

http://reefcentral.com/gallery/data/500/213612pic_6-med.jpg

Looking directly at the blue LEDs HURT my eyes!!!

These LEDs were super BRIGHT! As you may have noticed, I made a mistake. When I was wiring the LEDs I inverted one row on accident and instead of having white/blue/white/blue with alternating rows, I now have two rows that are identical. I don’t think this is such a bad thing, but it wasn’t what I intended so make sure you are very careful when you line up your LEDs!


Initial Results

I took a picture of the ceiling to gauge color uniformity (or lack thereof) with the included lenses. The LEDs give a nice “blue glow” and very uniform color even with my mistake. Although the picture appears purple, it is simply my camera that cannot handle the blues properly. I would say the color appears around 20,000K.

http://reefcentral.com/gallery/data/500/213612pic_8-med.jpg

I took some random readings of the LEDs with the lenses on an Apogee Quantum Meter at about 6” above the LEDs. The results were quite impressive as I was getting PPF readings of over 1000 µmol m-2 s-1.

Once again, the PURPLE is really BLUE – my camera can’t handle the energy output of the Blue LEDs.

http://reefcentral.com/gallery/data/500/213612pic_9-med.jpg

http://reefcentral.com/gallery/data/500/213612pic_10.jpg

Finishing 2nd String

With the positive results, I went ahead and put together the second string of LEDs in the same way that I did the first. However, this time I laid them out correctly so they alternated white/blue every LED and every row (see top two rows in picture below).

http://reefcentral.com/gallery/data/500/213612pic_11-med.jpg

I did all of the wiring without either screwing down the LEDs or using the Arctic Alumina Thermal Adhesive because I wanted to make sure I could do this correctly. Keep in mind the Thermal Adhesive is permanent so make sure the LEDs are lined up properly before you use it. I would have preferred to screw the LEDs to the heatsink so I could replace them if they fail, but I don’t have access to a mill for drilling and tapping screw holes into the heatsink.


Conclusion

I spent ~$300 for my LED fixture. This is tons cheaper than any pre-made LED fixtures on the market, which are hard to find these days due to patent issues. The only LED light I could find on the market is the epro LumenAQUA, which is $1200 for the 24 LED model at drsfostersmith.com

The build took a few hours and was quite fun. I have not tested the fixture on my tank yet but will do so as soon as I re-wire the first string and attach the LEDs via the Arctic Alumina adhesive. As a note, you should attach the LEDs to the heatsink with the adhesive and let it set for 24 hours before you start wiring. I’m hopeful that my results will be as spectacular as other members’ DIY luminaries. We’re all using the same LEDs, and as my initial results indicate, they’re bright, they put out an amazing amount of PPF / PAR / PUR, and the color is very nice, not to mention my power bill will be much lower and I never have to change bulbs again!

P.S. Please be very careful when you are building your LEDs. As you know, you’re working with lots of hot tools and electrical wiring and there is always a risk of electric shock or burning yourself or hurting yourself in other ways. If you’re not a certified electrician, you need to get professional assistance.

[der_wille_zur_macht]

Nice rig!

Hopefully threads like this will reinforce the fact that it's pretty easy to throw this sort of project together, and get more people on board.

[billrob71]

Do you have any pics of your tank lit with this set up?? Be nice to see.

[yupgopotty]

I'll try to have some pics of the set-up over my tank by this weekend. I'm setting the LEDs with thermal adhesive tonight so hopefully I'll have results for you guys asap. (btw, my tank isn't the most glamorous one on RC but hopefully these lights will help)

[merlock116]

Did you ever get any pics? How is the new light working out for you?

[shelburn61]

Love it! Just figured out how to fit both my skimmer and frag lighting over a 40g sump...

[titnguyen]

thank you info.

[reeftanknewbie]

What's the advantages of LED over other forms of lighting. I would think the obvious ones are the cost to run them, their size compared to MH, and that they run cool not hot. But what about light output for corals? do you have any threads you suggest I read on this as I would like to know more?

[shikhyung]

They use Q4 over Q5 Led, does it has any benefit?

[der_wille_zur_macht]

<a href=showthread.php?s=&postid=15413475#post15413475 target=_blank>Originally posted</a> by reeftanknewbie
What's the advantages of LED over other forms of lighting. I would think the obvious ones are the cost to run them, their size compared to MH, and that they run cool not hot. But what about light output for corals? do you have any threads you suggest I read on this as I would like to know more?

The monster thread here on RC has a lot of info:

http://reefcentral.com/forums/showthread.php?s=&threadid=1630589

There are several growth sequences, and PAR readings in that thread, which, IMHO prove that LED can give us the light we need for corals. Also, lots of other information out there on the 'net. LED lighting is just catching on now, but people have been doing it for years, if you dig deep enough.

Generally, LEDs have a higher upfront cost, but power consumption is less, and life is longer (no bulbs to replace), so cost over the life of a tank can be a lot less. In addition to the lower power consumption, heat transferred to the tank is less.

Also, LEDs allow nearly infinite customization of lighting hue, since you can dim different colors of LED to get a blended effect exactly the color you want.

Thirdly, LEDs are a completely different shape and size of package compared to a bulky MH lamp or flourescent tubes. This is an area that hasn't been exploited much yet IMHO, but there are all sorts of creative ways you could mount LEDs to light a fish tank - you no longer need a huge canopy or ugly pendant.

<a href=showthread.php?s=&postid=15414141#post15414141 target=_blank>Originally posted</a> by shikhyung
They use Q4 over Q5 Led, does it has any benefit?

I'm lost, who used Q4? Q4 and Q5 are both brightness bins for Cree XR-E cool white LEDs. Q5 is brighter - it gives off more light for the same amount of power consumption. If everything else was the same, that would be the only difference. As such, Q5 are preferable but the difference is only a few percent, so using Q4 wouldn't be the end of the world.

[yupgopotty]

merlock, sorry for the delay. It's been a crazy week. Should have pictures up shortly. However, FYI 1" spacing in between LEDs for a 40 degree lens is too far apart!! I'll try to take pictures to show what I mean.

shikhyung, are you referring to the Q4's in my build? I used these b/c the bin code seemed to match what many other people on RC were using with good results, and that's also what was included in my kit.

[markviiisvt4]

is there any benifit to either your way or soundwaves way with the buck pucks?

[yupgopotty]

I don't think the performance is going to vary very much, I just thought using a MW driver was much easier. Buck Pucks are going to need a separate AC/DC power supply and usually can only power 6 LEDs (at least to my knowledge). The MW driver I used can power 12-13 LEDs without an external power supply (it's built into the driver already) which makes the build easier.

I'm not sure if the Buck Pucks are dimmable or not, but the driver I used is not. There are other MW drivers that have that feature, I just got the simpler one because that feature wasn't important to me.

In the end I felt a MW driver was cheaper, easier to install, and would take up less space.

[markviiisvt4]

I like the simplicity of the MW drivers, but wanted to make sure i wasn't missing something. do you know where the dimmable drivers are availiable?

[Dp Raider]

Tnanks for the thread. Very easy to follow.

What size tank is this going on?

[yupgopotty]

markvii, I heard they were on back order 1-2 months for most places.

Dp Raider, glad you like the thread. This is going on a 15gallon tank.

[brocnizer]

Right as i was about to make the jump to build mine I came across two stumbling blocks.

1) this thread makes the process so much simpler than I planned and need a new plan.

2) or should I just get this: http://cgi.ebay.com/WHITE-BLUE-LED-Aquarium-Reef-corals-grow-light-Panel_W0QQitemZ390043587942QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5ad068d566&_trksid=p3286.c0.m14&_trkparms=65%3A12%7C66%3A2%7C39%3A1%7C72%3A1205%7C293%3A1%7C294%3A50

[yupgopotty]

The main issue I see here is that they are 1W LEDs, which is pretty inefficient. You're getting 36W of light, which is the equivalent of 12 x 3W LEDs like I used. If you add up the cost of doing it yourself, it'll be something like this:

3W LEDs + lenses: $8 x 12 pcs = $96
1 Mean Well driver (non-dimmable): $24
Heatsink (depends on size): ~$30
------------------------------------------
Total: ~$150 (plus a few misc. charges for wiring, solder, etc).

This is roughly the same price you're going to pay for the unit on ebay. However, the benefits would obviously be that you can customize it however you like and it would be on a much smaller space since you are only using 12 LEDs (instead of 36). Also, not sure what angle these collimators (lenses) on ebay are but you might want to take that into consideration as well.

Overall, I think building your own is pretty fun and isn't that difficult. Also, based on everybody's comments in other threads these 3W CREE LEDs will work. Not sure how reliable the one you'd buy on ebay would be, I'd look for more specifics on the brand of LED (and bin code) and the specifications.

[brocnizer]

good points!

I tend not to like ebay items to begin with. I found this light 2 months ago and have been aprehensive to buy it.


Your plan makes life very simple and just might do it myself. My only big issue left is how many LED's to place on my system. It is a 36 gallon corner tank.

[shikhyung]

Just curious, still in the learning curve...

[yupgopotty]

brocnizer, not sure but maybe 48? I think the kit I bought has a version that has 48 LEDs in it.. that would prob be the most convenient, but of course you'd have to want that driver and those lenses.

shikhyung, welcome to the club. I'm pretty new to this as well, but have done research for a few months so just trying to help out if I can.

[Dp Raider]

Wow! I've been considering LED's for my new build.
I like the look. I love the efficancy. I enjoy DIY. I don't want to replace bulbs.
However, if you are putting 12 LEDs on a 15 gallon and I used that ratio... I would need 144 on my 90... and I don't see that happening.

[saraiva]

What is the best ratio, 2 white and 1 blue ou 1 white and 1 blue ?

[yupgopotty]

Dp, I'm not sure what the exact ratio should be. It seems from what other users are doing to be a little over 1:1, so for your 90 gallon it'd prob be something like 100-110 LEDs. You can always try LEDs (maybe 48?) on one side and MH on the other if you set-up allows it, that way you can compare the look and growth of your corals.

Saraiva, I've seen most people on RC do 1 white:1 blue but I remember seeing the AquaIllumination setup as 2 white:1 blue (they had clusters of 3). I think this depends on the color temperature you want for your tank, if you want it higher (I'm guessing my 1:1 ratio gives off about 20k) then go for 1:1 otherwise 2:1 should be okay as well.

[Dp Raider]

That makes sense.
I saw a diy kit on the likn you posted above for a 48 LED set. I could do that on both sides for 96 total. That would run around $1000. I could set up MH with VHO for less but when you factor in heat, electric costs, and bulb replacement the LEDs start looking better and better.

[cykenp]

Awesome lights! Great directions as well!

Any PAR readings?

I am interested in the same system as yours but perhaps with dimmable drivers. Think it'll be enough for a SPS only tank?

[der_wille_zur_macht]

<a href=showthread.php?s=&postid=15417374#post15417374 target=_blank>Originally posted</a> by yupgopotty
The main issue I see here is that they are 1W LEDs, which is pretty inefficient. You're getting 36W of light, which is the equivalent of 12 x 3W LEDs like I used.

FWIW, just knowing the wattage of an LED is more or less totally useless. What you really need to know is lumens per watt. Some "high brightness LEDs (Luxeon I, III, V for instance) are down around 50 - 60 lumen/watt, while others (XR-E, Rebel) are around 90 lumens/watt.

So, one panel made from 48 3w LEDs might produce 2,400 lumens, while another might produce 4,300 lumens!

Hence, you REALLY MUST know exactly the model and bin of LED you are using. That's the thing that scares me about some of the "kits" and pre-made solutions out there - there is NO real meaningful information given.

[g8gxp]

if you have multiple drivers can you connect them all to the same power cord, or does each driver need a separate cord? I've got 10 of the 60-48P's, but i don't want a bazillion cords all over the place.

[der_wille_zur_macht]

You can wire them to the same power cord, within the limits of the wiring, connectors, outlet, etc. that you are using.

In other words, if you had 30 of them drawing 1 A each, you would NOT want to wire them to a standard NEMA 5-15 plug and try to plug it into a 20 A wall outlet.

Depending on how you are going to time the lights, you might want to put them on several power cords anyways. For instance, you could break your group of 10 drivers up into three groups, then stagger their "on" times by half an hour each, to give a more gradual dawn/dusk effect.

[yupgopotty]

cykenp, I don't have a PAR meter but need to get one. Does anyone know where I can get a fairly cheap one from?

As for the sps only tank, I'm not positive however I'd assume yes IF you used lenses. You'd obviously have to take into consideration the height and spread of the beam, but if you could figure that part out I haven't seen anybody say that LEDs won't work for sps corals. Perhaps you can ask again in Soundwave's thread to see if anyone there has had experience with sps tanks.

der_wille, thanks for clarifying! I made sure my kit had the same bin codes as what other users seemed to be using before buying.

[saraiva]

The Mean well LPC-35-700W Drive (http://www.meanwell.com/search/lpc-35/default.htm) is suitable for 12 Cree led´s, but in MW data sheet DC Voltage Range is 9 ~ 48V.
What that means?
1 Cree led is 3,5V and 12 Cree LED´s are 42V.

[der_wille_zur_macht]

<a href=showthread.php?s=&postid=15424730#post15424730 target=_blank>Originally posted</a> by yupgopotty
I haven't seen anybody say that LEDs won't work for sps corals. Perhaps you can ask again in Soundwave's thread to see if anyone there has had experience with sps tanks.

FWIW, soundwave has SPS in his tank, and has posted excellent growth shots in his thread - of course they are probably a dozen pages back by now. And, he's using less LED per unit of tank size than several other folks.

der_wille, thanks for clarifying! I made sure my kit had the same bin codes as what other users seemed to be using before buying.

Good to hear - I made that post above in the hopes that others considering kit or pre-built panels would take the time to check, too - since several of the LED kits or panels commonly on ebay do NOT include this important information.

[g8gxp]

Well, i'm planning on hooking them up to my controller for the dawn/dusk stuff, so i was just planning to increase the output of the whole array over a graduated time vs. turning banks of lights on in some sequence, so based on this it would probably be better to have 1 cord per driver? Not that i would ever turn them all up to 100% but just to be safe?

<a href=showthread.php?s=&postid=15424655#post15424655 target=_blank>Originally posted</a> by der_wille_zur_macht
You can wire them to the same power cord, within the limits of the wiring, connectors, outlet, etc. that you are using.

In other words, if you had 30 of them drawing 1 A each, you would NOT want to wire them to a standard NEMA 5-15 plug and try to plug it into a 20 A wall outlet.

Depending on how you are going to time the lights, you might want to put them on several power cords anyways. For instance, you could break your group of 10 drivers up into three groups, then stagger their "on" times by half an hour each, to give a more gradual dawn/dusk effect.

[der_wille_zur_macht]

If you are dimming with the dim circuit on the drivers, you can do that totally independantly of power cords, etc. Though, I would probably still use some sort of timer (plug in appliance timers, or a controller) to turn power on/off to the drivers, rather than just dim them down to zero when you want them off.

[bobbyrocco]

I have some questions in regard to your comment on how 1" spacing for 40 degree optics is to far apart. I take it that you are getting the spotlight effect so you need to put them closer together inorder to get rid of that?

I am lighting a 120 gallon so I was looking at getting 2 48led kits for a total of 96 LEDs to light the entire tank but I was thinking I could put the optics on every other LED to get both penetration of light and spread throughout the tank. The only thing is I dont quite know how to space each LED to make sure it looks kind of consistent throughout the tank?

Any ideas?

[yupgopotty]

saraiva, I believe that means it can handle any load between 9 - 48V. For the CREEs that I used, the consensus seems to be that they run at about 3.2V at 700mA. Hence, 48/3.2 = 15 LEDs maximum (even at 3.5V, this driver can technically handle 48/3.5 = 13.7 LEDs). I think 12-13 is much safer, and I'm running 12 with no problems.

[yupgopotty]

<a href=showthread.php?s=&postid=15426184#post15426184 target=_blank>Originally posted</a> by bobbyrocco
I have some questions in regard to your comment on how 1" spacing for 40 degree optics is to far apart. I take it that you are getting the spotlight effect so you need to put them closer together inorder to get rid of that?


I think it has to do with the depth of the tank. My tank is 13" deep and I put it on a temporary stand (fish food) that is about 4" tall, so the bottom of the tank is roughly 17" from the LEDs. Towards the lower part of the tank, the light looks uniform and awesome. However, higher up in the tank you can see a few white and blue beams where they don't cross yet. It's hard to tell from these pictures but I'll try to post more detailed pictures later on (I'll try to compare them to the MH I have as well as a flourescent).

http://reefcentral.com/gallery/data/500/213612led_with_lenses.jpg

Here's a picture of the same light w/ the lenses off and directly above the tank.

http://reefcentral.com/gallery/data/500/213612leds_no_lenses.jpg

For a smaller tank like mine I would have preferred to put the LEDs a bit closer together (perhaps 0.75"?). Since you have a 120g, the 1" spacing might work out pretty well for you (or may not even be wide enough!)

[ROBLOW]

nice read....i would like to see if you would get the same growth out of led as u would mh?

[t0pcat]

Where did you get the mean well ps from?

Looking good by the way.;)

[der_wille_zur_macht]

ROBLOW, go look in Soundwave's thread - he has posted growth sequences showing pretty good results. Others have on this forum and other reef forums on the net, but Soundwave's are the easiest to find. It is certainly the case that LED is capable of growth comparable to MH.

[yupgopotty]

<a href=showthread.php?s=&postid=15429411#post15429411 target=_blank>Originally posted</a> by t0pcat
Where did you get the mean well ps from?

Looking good by the way.;)

Thanks. I got the drivers from www.rapidled.com (as part of the 24 LED kit).

[saraiva]

What is the colour temperature from the Cree led´s used ?

[der_wille_zur_macht]

Most people are using XR-E "cool white" with WC or WG color bins, which equates to about 6500k or 6000k respectively. In reality, they appear a little whiter than that makes them sound, since they have really strong blue peaks. Probably equivalent to some of the yellower 10k bulbs or daylight we are used to using.

It's hard to talk about "color temperature" for the blue and royal blue LEDs, since they emit an extremely narrow range of wavelengths of light, but it's more or less right in the range where most actinic flourescents are, so you can compare it to that.

[shikhyung]

With the lense you have to raise the fixture uphigh, so what is the benefit w/wo lense. thanks.

[wesley6610]

I believe that the benefit without lenses is a wide spread of light, versus focused with lenses. That wider spread also equals less penetration if it is a deeper tank.

[yupgopotty]

The biggest difference that I've noticed is the lenses make the LEDs much much brighter since the light is concentrated into a much smaller area. Personally, I think as long as the light can penetrate into your tank it doesn't matter whether you use a lens or not. For deeper tanks I would definitely go with the lenses but I've never tried it out and I know many people on RC choose not to use lenses and still have had fantastic results.

[wesley6610]

What depth is your tank yupgopotty?

[ejg001]

TruVU 15 gallon is 24x13x12 according to their website, so 12" deep should be right.

[yupgopotty]

yep, i think that is correct. that's why I put the LEDs w/ lenses slightly elevated (though I could have avoided this had I put the LEDs closer together...live and learn).

[Dp Raider]

Does anybody do a combination of lenses and no lenses? Wondering if on a 24" deep tank this would be a good comprimise. The higher corals don't get burnt and the lower ones still get good light.

[g8gxp]

<a href=showthread.php?s=&postid=15437573#post15437573 target=_blank>Originally posted</a> by Dp Raider
Does anybody do a combination of lenses and no lenses? Wondering if on a 24" deep tank this would be a good comprimise. The higher corals don't get burnt and the lower ones still get good light.

I will be trying this when i build mine. It's 26" deep but the rock pile goes up as high as 10" from the water line. Plus my tank has a center brace in the middle so i'll need to put no-lense lights near the middle to cover that area.

[der_wille_zur_macht]

<a href=showthread.php?s=&postid=15437622#post15437622 target=_blank>Originally posted</a> by g8gxp
Plus my tank has a center brace in the middle

you could also slant some of the LEDs near the middle of the tank, to shoot light under the center brace.

I see this sort of flexibility as a huge advantage to LEDs that hasn't really been tapped yet. You can have extremely fine control over exactly what color and intensity of light hits exactly which portion of your tank at exactly what angle.

[jimnrose]

Center brace concern: I also am building an LED fixture (72 in 5 rows on 4" offset grid) which includes 6 LED's over 2 acrylic cross braces (3 led's/brace). I'm guessing the light will penetrate thru the acrylic provided I keep the braces clean (only 1" above the tank water line). Will the salt spray deflect/absorb the light? My LEd's are in transit and the grid could be changed to avoid the brace areas. Jim

[wesley6610]

I was wondering the same thing about light penetration through seemingly clear objects. I am trying to determine if I place the LED array closer to the tank and use an acrylic or glass splash guard if it will hinder the light. Or if its better to just sit it up high and use optics and pray for no "spot-light" effect.

[jimnrose]

On a T5 thread, it was recommended to keep the lights at least 4" above the water line, to avoid excessive salt spray. I'm sure it varies depending on the water velocity at the surface. Cross braces are usually close to the water line, therefore it would be impossible to keep the surface clean. I'm thinkiing of drilling 3,
1" holes i each crossbrace (center of a 3"wide brace) & use 40 degree optics to get half of the light thru without an interference.

[ejg001]

yupgopotty: at what height do you think you would need to raise the light so that the lighting is even, i.e. no 'spotlighting' effect?

or, what distance below the light do you think the rockwork would need to be so that with lenses, the light would be even? i'm not really concerned about the upper level of the tank, just the rockwork.

thanks!!!

[yupgopotty]

I think you'd be safe at about 12" or so (with 1" in between LEDs). Again, if this is too deep then you can always space the LEDs closer together or raise the lights above your tank.

[merlock116]

has anyone used rapidled.com?

[markviiisvt4]

I think some one needs to find a little aimable mount so that each LED can be aimed individually

[timmmysli]

ejg001 I think the whole spotlight effect is unlikley to happen unless you use really tight optics.

I have 20 degree optics and the led fixture is 250mm above the waterline (tank depth 350mm). I can't see any form of singular spotlight effect from individual leds. If I was to place my leds system at the waterlevel well thats a different story, I have done that and you can see the "spotlight" look but thats an extreme case.

:cheers:

[timmmysli]

markviiisvt4 there are led optics with rotatable joint. They are more expensive than each led so I would create small led units (say groups of 6leds) that you can point or aim at whatever coral you choose instead of throwing away heeps on a little gimmick.

Thats the idea for my next led build, a group of seperatly controled led spotlights that can be shifted and aimed any position in the tank.

[saraiva]

yupgopotty, do you use a blower over the heatsink ?

[wesley6610]

timmmysli do you have a link for the rotational optics that you mentioned? Does it say what the range of motion and default degree of them are?

[yupgopotty]

<a href=showthread.php?s=&postid=15458400#post15458400 target=_blank>Originally posted</a> by saraiva
yupgopotty, do you use a blower over the heatsink ?

I placed a very simple CPU-type fan over the heatsink (no screws and it's not attached, it just sits on top of the heatsink) though the unit would probably work just as well without it.

[brocnizer]

do you think your tank looks too blue? Through pictures it is hard to tell if I want to do 1:1 white: blue or go for 2:1

[yupgopotty]

In my original post the purple pictures are actually a very blue glow. Personally I don't think it's too blue though I haven't seen what the blue for a 2:1 ratio looks like so it's hard for me to comment on that.

[wesley6610]

How is your coral growth progressing with your current ratio or blues to whites?

[yupgopotty]

I never had great coral growth in my tank to begin with. As you can see from the pics I posted earlier, there just isn't a whole lot of coral in my tank. That being said, they are maintaining the same as per my previous lighting system (MH) and there have been no signs of decline or wear on the corals after the switch to LEDs.

[ejg001]

<a href=showthread.php?s=&postid=15424779#post15424779 target=_blank>Originally posted</a> by der_wille_zur_macht
FWIW, soundwave has SPS in his tank, and has posted excellent growth shots in his thread - of course they are probably a dozen pages back by now. And, he's using less LED per unit of tank size than several other folks.

I also read (parts) of Shockwave's MONSTER thread. He seemed to have decent SPS growth with these specific LEDs. Hopefully you'll experience the same thing and your corals will start to grow just like his!!! :)

[wesley6610]

I am getting in almost all of my parts between tomorrow and Friday and will start documenting my build this weekend. I too am lighting a 75 gallon tank, but I added 12 more LED's per heatsink than Soundwave with optics to ensure that I get good PAR throughout my tank. We will see if my modifications actually work soon enough...

[t0pcat]

i ordered some of these leds
Ebsy Leds (http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=350220429606&ssPageName=STRK:MEWAX:IT)

When i tested one led it blew shortly after switching on? any ideas?

its rated for 700ma and i am using the LPC-35-700

Thanks in advance
Tony

[der_wille_zur_macht]

The emitter on that star kinda looks like a Seol Semiconductor P4, but it's hard to tell.

Can you describe exactly how you wired it to the driver? Was it on a heatsink, or was the star just hanging out all lonely?

[t0pcat]

it was on a heat sink but it ran for about a millisecond.... didnt seem to have time to get hot.

:o I just hooked up the negative and positive in the correct direction

[der_wille_zur_macht]

I'd have to dig out the datasheet for that driver, but I'm wondering if it has a minimum output voltage - like, 5v or 9v. If this is the case, you should NEVER connect a single LED to it, or even multiple LEDs, unless the forward voltage of your string is higher than this minimum. Otherwise, it'll cook the LED in no time, since it won't be able to cut the voltage low enough to control the current.

[der_wille_zur_macht]

Yeah. Here's the datasheet:

http://www.trcelectronics.com/Meanwell/pdf/lpc35.pdf

It has a minimum of 9v output, so you need at least three of those LED in series.

[t0pcat]

Thanks for that i am a bit rusty on the old electronics 8)

[g8gxp]

<a href=showthread.php?s=&postid=15503197#post15503197 target=_blank>Originally posted</a> by der_wille_zur_macht
I'd have to dig out the datasheet for that driver, but I'm wondering if it has a minimum output voltage - like, 5v or 9v. If this is the case, you should NEVER connect a single LED to it, or even multiple LEDs, unless the forward voltage of your string is higher than this minimum. Otherwise, it'll cook the LED in no time, since it won't be able to cut the voltage low enough to control the current.

This should not be a problem with adjustable drivers, correct? The reason i ask is that I have the meanwell60-48 which is adjustable. i hooked it up to a single cree to test it out, got a momentary flash and then nothing. I thought it was fried but someone else said that it shouldn't be with the fully adjustable driver.

[der_wille_zur_macht]

<a href=showthread.php?s=&postid=15509785#post15509785 target=_blank>Originally posted</a> by g8gxp
This should not be a problem with adjustable drivers, correct? The reason i ask is that I have the meanwell60-48 which is adjustable. i hooked it up to a single cree to test it out, got a momentary flash and then nothing. I thought it was fried but someone else said that it shouldn't be with the fully adjustable driver.

You really have to look at the specs of the individual driver to answer this. It likely won't depend specifically on wether or not it's adjustable.

And I hate to say it, but unless you tripped some protection mechanism in the driver, a bright flash followed by nothing is almost always a sign that the LED is now dead.

[g8gxp]

http://www.powergatellc.com/pdfs/ELN-60.pdf

This is the datasheet for the driver i am using. ELN-60-48. I'm a moron with electrical so i really don't understand what i need to look for. I basically did the same thing yugo did, i took an old computer power cable, spliced it and connected it to the driver, then held the driver contacts to the LED. Actully it didn't die completely, but after the flash, the LED is just barely glowing. I wonder if it was just because the connection was weak?? but why the initial flash?

[ccLansman]

I didn’t see this mentioned but if I missed it sorry for the double question..

What made you hook up the lights in series instead of parallel?

If you would have hooked them up in parallel you could have lowered the total loaded resistance and might have gotten away with a smaller power supply.

Since in series you have ..

Power supply –resistance---resistance---resistance … all adding

In parallel you would have run

Power supply ---resistance _____ added but resistance halved…
---resistance

Also if one breaks you won’t lose the whole thing if they are parallel.

To answer your question g8gxp:::

If it flashed and is now dim you over drove the LED and its basically dead. LEDS can only handle so many volts/amps across the diodes; if you jolt it like that you melted/destroyed the leds.

[der_wille_zur_macht]

OK - That driver has "no minimum load" and a minimum Vout of 3v, which should be well below the "explode" threshold of an XR-E.

Troubleshooting exactly what happened to your LED is gonna be a little tough. . .

[der_wille_zur_macht]

<a href=showthread.php?s=&postid=15511068#post15511068 target=_blank>Originally posted</a> by ccLansman
I didn’t see this mentioned but if I missed it sorry for the double question..

What made you hook up the lights in series instead of parallel?



If you are talking about wiring the individual LEDs to the driver in series or parallel, it's pretty much a given with HB LEDs that you wire in series. This is for a number of reasons, including load balancing and safety.

If you have several parallel LEDs or chains of LEDs running from a single driver, there may be ever-so-slight variances in each string. Since the (constant current) driver can't differentiate or load balance, current won't be split evenly, and you'll likely end up with one or more strings overdriven, and one or more underdriven. Since so many people are driving these LEDs to within inches of their lives, this could either kill LEDs (slightly over driven) or lead to poor performance (slightly under driven.)

Also, if you have many parallel strings of LEDs and one LED in one of those strings burns out, the driver will continue to pump out the same current, only now it's ALL going through n-1 strings of LEDs, instead of n. If you had, for instance, two LEDs in parallel, the one remaining LED will now be getting twice the current you had intended, and will likely self destruct.

Also if one breaks you won’t lose the whole thing if they are parallel.

I think you've got this backwards. . .

[ccLansman]

thanks for the info der_wille, im looking to setup an LED strip in an extra hood i have for my 12gal jbj nano dx and this will greatly simplify my struggles :)

[der_wille_zur_macht]

Plus, most of the drivers people use are constant current drivers, designed to provide current in the range that one LED can handle, at a voltage several times what one LED drops. As such, they're really geared towards series operation (since, in series, current stays the same but voltage is additive).

[wesley6610]

That was a lot easier to understand der_wille....than most of these diagrams and google searches of wiring LED's in a series versus parallel, thanks!

[kentrob11]

Hey guys...Any comments on this setup for an oceanic 58 gallon? I want to do mostly sps so intensity would be key here. Do I need to crowd them a little better and do 48 insted? The grid is in inches....thanks!
http://reefcentral.com/gallery/data/500/8543LED_58-med.JPG

[Saltcity]

Has anyone done this for a "big" tank?
I'm planning a basement in wall tank around 130-150 gallons and would really like to do LED lighting.

[jerryz]

I would aim for 2.5 inches x 3 inches so a little closer together. Also the # of RB is low enough it's going to be very white without a lot of color blending. A 50/50 mix gets you to 14K or so in perceived color.

[der_wille_zur_macht]

<a href=showthread.php?s=&postid=15529467#post15529467 target=_blank>Originally posted</a> by Reeforbust
Has anyone done this for a "big" tank?
I'm planning a basement in wall tank around 130-150 gallons and would really like to do LED lighting.

Soundwave's 75g is probably among the biggest that have been discussed and well documented in this forum. Though, IMHO, the advantages of LED are just as applicable to really big tanks, though given the initial investment it's understandable that it isn't common practice yet.

I will be starting construction on a big tank within the next year or two (though I've been saying that for a year or two :lol: ) that will likely be LED lit.

jerryz, to further qualify your statement about 1:1 looking like 14k, it really depends on the specific bin and model of LEDs being used. I have a small light for my nano that I've switched around in various ratios of cool white Rebels, cool white XR-E, royal blue XR-E, and plain blue Rebels, and very sublte differences (i.e. WG color binned cool white XR-E vs WB) can make a pretty big difference. So I think we need to be careful with generalizations that we talk specifically about exactly which LEDs we're talking about.

[Saltcity]

Soundwave's write up really got me leaning towards LED's..... Seems like you could just make it bigger for a bigger tank BUT I AM AN ELECTRICAL NUMSKULL!!!!! :)

[jerryz]

You're right I guess the point I was trying to make, not well, was that at 2:1 CW/RB the tank could end up fairly low on the perceived spectrum in K if the CWs are driven at max current.

<a href=showthread.php?s=&postid=15529545#post15529545 target=_blank>Originally posted</a> by der_wille_zur_macht
Soundwave's 75g is probably among the biggest that have been discussed and well documented in this forum. Though, IMHO, the advantages of LED are just as applicable to really big tanks, though given the initial investment it's understandable that it isn't common practice yet.

I will be starting construction on a big tank within the next year or two (though I've been saying that for a year or two :lol: ) that will likely be LED lit.

jerryz, to further qualify your statement about 1:1 looking like 14k, it really depends on the specific bin and model of LEDs being used. I have a small light for my nano that I've switched around in various ratios of cool white Rebels, cool white XR-E, royal blue XR-E, and plain blue Rebels, and very sublte differences (i.e. WG color binned cool white XR-E vs WB) can make a pretty big difference. So I think we need to be careful with generalizations that we talk specifically about exactly which LEDs we're talking about.

[der_wille_zur_macht]

<a href=showthread.php?s=&postid=15534497#post15534497 target=_blank>Originally posted</a> by jerryz
You're right I guess the point I was trying to make, not well, was that at 2:1 CW/RB the tank could end up fairly low on the perceived spectrum in K if the CWs are driven at max current.

I absolutely agree. I tend to think out loud some times, if you haven't noticed. :lol: I didn't post in disagreement, rather it was just a thought I had when I saw your comment.

[ecomdesign]

are the dimmable meanwell drivers easy to adjust? I cant remember for sure, but I think I saw that they are not as easy to adjust as buckpucks.

[jerryz]

The Meanwells are dimmable with a pwm circuit. SLightly more complex to build one. But only slightly. A couple of caps and a 555 timer pretty much do it.

[der_wille_zur_macht]

It depends on which mean well driver you get - they make most models in two versions: dimmable via PWM, or dimmable via 0 - 10v signal. As jerryz indicated, for the PWM models, you need to build a circuit to generate a PWM signal, which isn't terrible. However, if you're afraid if electronics, the 0-10v models are probably easier to deal with, since you can dim them with a potentiometer and a wall wart.

[bobbyrocco]

I am in the building stage of a fairly large tank LED build. It is for a 120g (48x24x24) and im doing the following:

70 XR-E Q5 cool white
70 XR-E RB
all will have 60 degree optics with some 40 degree mixed in.
12 Meanwell dimmable drivers with the 0-10v dimmers plan to use the RKL controller to dim once the upgrade comes out.
2 Large 40" heatsinks from Heatsinkusa side-by-side.
Using thermal adhesive tape(no way can I drill and tap 280 holes:)

It is very exspensive to buy the parts intially but I am hoping they will pay for themselves in 3 years. I just finished planning the layout and the wiring is going to be a pain in the @_%.
I got a lot of help from this thread and evil over on Nano-reef so thanks everyone.
http://reefcentral.com/gallery/data/500/81571Heatsink.jpg
http://reefcentral.com/gallery/data/500/81571LED_Layout.jpg

[tahiriqbal]

looking very sharp.....

[kcress]

Wow a mondo build.

You should consider drilling and tapping mounting holes for the wiring loom. Screw down those tie wrap bases then you just route all your wires down the wire channels and tie wrap them when you're done. They will also prevent a disaster if whatever tape lets go in the future, by holding the unmounted LED above the water, or splash shield.

[ecomdesign]

<a href=showthread.php?s=&postid=15538117#post15538117 target=_blank>Originally posted</a> by der_wille_zur_macht
It depends on which mean well driver you get - they make most models in two versions: dimmable via PWM, or dimmable via 0 - 10v signal. As jerryz indicated, for the PWM models, you need to build a circuit to generate a PWM signal, which isn't terrible. However, if you're afraid if electronics, the 0-10v models are probably easier to deal with, since you can dim them with a potentiometer and a wall wart.

I'm not that knowledgeable with electronics, so I guess I'd be better to go with the 0-10v way instead. I'm planning to start buying everything in November. The wife has given me the go a head!

[bobbyrocco]

Thanks for the advice kcress. I am planning on a splash shield so if a led does give way it won't end up in the tank. I also plan to attach the drivers to the top of the heatsink and will drill holes for the wire to go through to the LEDs. I just don't know what to use to fasten the drivers down on the fins?

[wesley6610]

You are going to attach your drivers directly to the heatsink fins? Why not in a remote location, like directly above if you are using a canopy or on the side of the wall away from direct splash and salt creep? Are you planning on using fans to cool the heatsink and if so won't your drivers be in the way and generating heat of their own? Just some things to think about before you committ to that location.

[yupgopotty]

Just out of curiosity, if you are planning on putting the drivers on top of the heatsinks why are you going to fasten them down? I would imagine your unit wouldn't move very often so I don't see the advantage of having them fastened down.

For my fan, I just sit it on top of the heatsink w/o any screws or fasteners and it seems to work just fine. Wouldn't you be able to do that with your drivers as well?

[der_wille_zur_macht]

At the very least, drill a hole in one or more of the heatsink fans and loop a zip tie through. It would REALLY SUCK to lose your tank because a stray elbow knocked some electronics into the water.

[bobbyrocco]

Your right that the light shouldn't move but just in case I would like them held down some how plus I will have 12 drivers and two fans on top of the heatsink and I want them to stay where they are suppose too! The zip tie seems like a simple soultion!

[yupgopotty]

actually the zip tie is a great idea, der_wille. I think I might do the same for my fan as well.

[wesley6610]

Sounds like a good idea to me as well, though I have one question, does anyone think that vibration or noise will result from the fan sitting directly on the heatsink? Could rubber gromet feet with a ziptie alleviate the potential noise? Just a thought...

[der_wille_zur_macht]

I haven't noticed any vibration or noise, but a grommet would certainly not be a bad idea.

Keep in mind though that these fans are basically meant to be screwed directly to a metal chassis (in a PC) without any isolation. If one of them is vibrating to the point that it's creating extra noise, it's probably so far off balance that it's gonna die soon anyways.

[yupgopotty]

My fan sits on top of my heatsink and I haven't heard any noise or vibrations either. I think it's fine, as long as it doesn't fall into the water accidentally.

[jerl77]

nice light you got your self there is there a way to dim them yet??

[yupgopotty]

Hi jerl, I chose not to go with dimmable drivers. At the time of my build the dimmable drivers were hard to come by (they may still be) and cost about 3 times as much as the drivers I ended up using (Mean Well LPC-35-700). Also, since I don't have a ton of corals in my tank I felt it was unnecessary to gradually turn the lights on/off. I just set the lights up on a timer and forget about them.

[jerl77]

can you dim them what do i need to do to dim building one for my 40 breeder what to dim them with out buy 80 buckpuck drivers

[yupgopotty]

Nope, I can't dim my lights. What I could have done is set up 12 LEDs on one power cord and the other 12 on another so I could turn them on one batch at a time. However, I wired them all up together so now it's 24 LEDs or none, simply all on or all off.

If you need dimmable drivers and don't want to use buck pucks look for the dimmable Mean Well driver. I believe it's the ELN series. You might need a controller to use it though (I'm not sure how they work), you can dig through Soundwave's thread to find out what ppl are using or maybe someone is helpful enough here to let you know.

[madadi]

just remember that if you dont use buckpucks, the meanwells dont require an external power source and they can use line current so you end up spending about the same. dimming is not required but its a nice feature if you can dim the whites and leds separately. you can dial the color in any where from 6.5k to 20k!!!

[justinm0424]

for your fans can't you just use heatsink fans for pc's? If they're standard pc size fans they make heatsink clips for proc heatsinks and other things. if the heatsink is the same width apart you shouldn't have a problem finding one or modding it to fit. Worse case it'll only slide side to side then you can easily put some glue on the clips. It seems better than drilling into the fins

[menari]

Has anyone figured out how to use the dimming function on the Mean Well ELN-60-48P dimmable driver? I know it's been discussed to death in other threads but the discussions seem to go in several different directions. Does anyone know of a easy to use digital controller that can be purchased cheap?

[wesley6610]

I'm not sure if cheap and reef keeping can be used together at this stage of the game...but I would be interested too in an affordable digital controller for dimming.

[der_wille_zur_macht]

Depends on what you guys mean by "dimming with a controller" and "affordable."

If you want something you can tweak by hand to adjust color temperature, it's dirt simple. If you got the 0-10VDC version of the meanwells, you just need a potentiometer and a power supply. If you got the PWM version, you need to generate a PWM signal, which is about $2 in parts and 10 minutes of soldering - or just go spend $10 on something premade.

If you want programmable, automated dimming, then it depends on how much interest you have in actually DIY'ing a solution. I've got a DIY lighting controller based on the open-source arduino that'll fade several banks of LEDs up and down to simulate sunrise, travel across the sky, and sunset. It'll also simulate moon cycles at night, and do a "storm mode" where it dims the lights for a variable amount of time (an hour or so) every few days to simulate clouds passing across the sky.

All this from an arduino-clone kit that cost $12, an RTC chip that cost $5 or so, plus a few bucks of odds and ends I had anyways. Of course, the big effort is coding it all, but I've done that already, so if anyone else wants to go this route I'll share what I have.

Or, you could go spend $500 on a reef controller capable of 0-10v or PWM output to get a few channels of programmable control for your meanwells. ;)

[wesley6610]

der_wille_zur_macht, where can i start researching some of this stuff since it seems very electrical/computer engineering involved? i would like to save money and add to my DIY light, but i need a good amount of instruction first as well, any links that you could provide would be great.

[der_wille_zur_macht]

www.ardunio.cc is the homepage for Arduino. It's a board (hardware) and development environment (software on your PC) designed to make it easy for average people to create projects based on the AVR microcontrollers from atmel. Check out that site, and the forum located there, for some ideas on how people are using arduinos. I'm really thrilled I stumbled across this stuff, because it lets IT folk like me do dangerous things out in the real world, instead of being confined to the digital world.

You can download the software from that site. You'll need hardware, too - an ardunio-compatible board. The current official board is called the duemilanove. You can buy one from a number of vendors listed on that site. Since it's an open source project, you can also get a clone from a number of vendors. This is the route I took, since it's cheaper and gives you only what you want. The duemilanove runs about $30, and has onboard USB connectivity for programming, plus some other features I didn't care about. Since I set out to design something to build and leave in place, I went with a solution that keeps the board pretty stripped down.

www.moderndevice.com is the vendor I used for the board. I bought their kit called the RBBB (really bare bones board), and their USB-BUB, which is a dongle that lets you plug it into a PC's USB port to program it. The RBBB kit is about $12, and the BUB is about $12. You'll only ever need one BUB, you can re-use it - so for additional projects, you only need the controller.

Also, I have an RTC (real time clock) in my project to keep track of time. The Arduino has timekeeping ability, but it's reset when the power goes out. Adding a hardware RTC lets you keep track of the time with a battery backed-chip, so when power comes back on, the controller knows what time it is. I bought a raw chip (DS1307) and added a few external components to get this capability, it was maybe $5. You can get pre-made RTCs based on this chip for around $10 - $20.

If you get drivers that can take a PWM signal, that's all you need, besides hookup wire, a project box to put it in, and some other odds and ends. The Arduino has 6 PWM outputs, so you'll be able to program 6 channels of LED lighting from it.

So I guess in my eagerness I was misrepresenting cost a bit. You could be functional for maybe $40 - $50 investment, if you're choosy, and want to control a few channels of LED lighting.

I'm not online much right now (no internet connection at home until next week) but lemme know if you have more questions, and I'll answer when I get a chance.

Of course, the above applies if you want an LED controller. The arduino can also function as a controller for your entire reef, the sky's really the limit. There's an active thread in here about someone who's making an arduino-based reef controller called the reef buddy, and there are several other threads and blogs out there on the internet about doing this, too - I have many of them bookmarked, but the bookmarks are all on my home PC which, of course, is offline right now. But, other people are interfacing with temperature sensors, pH probes, LCD screens, auto topoff devices, automated water changing, etc. - hardware cost grows a bit as you add functionality, but it's on a vastly different price scale than most commercial solutions, which of course are aimed at people who want something out of the box, instead of DIY.

[wesley6610]

Perfect, I will get started researching all of this once I get home, thanks for the wealth of information!

[JLopez]

Sorry to ask, maybe you mentioned this but I dont want to read 120 posts to find out lol...You got this kit on ebay? can you provide the name of the seller or what you searched for on ebay? Thanks...great build btw! love it, im gonna put it on my small tank in my room.

[laverda]

If I want to get controlable Meanwells to use with my AquaControllers, would I want the 0-10VDC version of the Meanwells?

[ejg001]

<a href=showthread.php?s=&postid=15749949#post15749949 target=_blank>Originally posted</a> by JLopez
Sorry to ask, maybe you mentioned this but I dont want to read 120 posts to find out lol...You got this kit on ebay? can you provide the name of the seller or what you searched for on ebay? Thanks...great build btw! love it, im gonna put it on my small tank in my room.

I believe yup mentioned somewhere in the first post that the kit was from rapidled.com

[ejg001]

<a href=showthread.php?s=&postid=15752095#post15752095 target=_blank>Originally posted</a> by laverda
If I want to get controlable Meanwells to use with my AquaControllers, would I want the 0-10VDC version of the Meanwells?

I don't know much about AquaControllers, but I do know that one version of the MW Dimmable driver requires a PWM signal and the other an analog 1-10v signal. The datasheet or owners manual for your specific AquaController might have that detail...

For example, the AquaController Apex has 4 0-10v ports so you would need 0-10v dimmable drivers, not PWM.

<a href=http://www.neptunesys.com/index.php?option=com_content&task=view&id=49&Itemid=48>Data Sheets for AquaControllers</a>

If we knew your specific model it would help.

[MentalDragon]

I'm looking into doing this setup for a 75g tank. 48" x 18 x 20.

Is there a "standard" calculation on how many 3w LEDs to use to replace a 250w 20k MH Lamp using the exact kit in this thread? I'm asking because I want the LEDs but I don't want to have less lighting.

Basically I'm wanting to replace: 2 x 250w 20k lamps with 2 x 96w 32" PC supplement.

Thanks for your help!

[ejg001]

Is there a "standard" calculation on how many 3w LEDs to use to replace a 250w 20k MH Lamp using the exact kit in this thread?

Hi, there isn't a "standard" calculation on exactly how many 3w LEDs to use to replace a 250w 20k MH Lamp, however there are "case studies." Soundwave, in his thread, has a 75g tank and he uses 48 LEDs and has good coral growth. It is to be noted he does NOT use optics. Putting optics/lenses on the LEDs would help maximize the effectiveness of the LEDs. His thread is linked in the original post of this thread.

As for the lumens, PAR, and PUR output, it seems to be from the threads I've read, that LEDs are very capable of being the sole lighting source for a reef.

So, as an entirely subjective guestimate, 48 LEDs will do, but if you are concerned about not enough lighting, 12 more on a 75g, totaling 60, seems to be sufficient.

[MentalDragon]

Hi, there isn't a "standard" calculation on exactly how many 3w LEDs to use to replace a 250w 20k MH Lamp, however there are "case studies." Soundwave, in his thread, has a 75g tank and he uses 48 LEDs and has good coral growth. It is to be noted he does NOT use optics. Putting optics/lenses on the LEDs would help maximize the effectiveness of the LEDs. His thread is linked in the original post of this thread.

As for the lumens, PAR, and PUR output, it seems to be from the threads I've read, that LEDs are very capable of being the sole lighting source for a reef.

So, as an entirely subjective guestimate, 48 LEDs will do, but if you are concerned about not enough lighting, 12 more on a 75g, totaling 60, seems to be sufficient.

Thanks for the reply. I did read Soundwave's and that is why I was confused. In his thread he only used 48 leds ... 24 on each side. Then in this thread, there were a couple postings that said do a 1xLED:1xGal ratio. I do plan on using 40deg lenses so I guess 48 should be fine. That sounds better because I was about to order 2 x 48 kits.

[der_wille_zur_macht]

Mental,

It's all a guessing game at this point. I don't like X/gallon rules at all, because they don't account for dimensional differences in tanks. And, with LEDs, that is perhaps more important than other types of lighting, because we have to plan out how to cover the entire tank, in addition to getting the "right" amount of lumens in the tank. If you use flouescent tubes of any sort, you just get tubes the same length as the tank and you're set. If you use MH, you get a lamp for every 2' of tank length.

In the same way that people claim an MH lamp will cover a certain number of square feet (typically a 2' x 2' area), I think it's important to consider the equivalent for LEDs. Instead of square feet per LED, we might use square inches per LED.

So far, most builds have been in the 10 - 20 square inches of tank surface per LED range. Soundwave is on the low end (i.e. closer to 20) and others are down near 10. If you have a deeper tank and/or want more intensity for SPS, you want to be closer to 10. If you don't care so much about intensity or will have a mixed reef, or have a shallow tank, 20 is probably fine. If you have optics narrower than 40 degrees or so, you NEED to be close to 10 square inches per LED, or else you'll end up with shafts of light surrounded by darkness.

Of course, this is all assuming you are using standard practice - XR-E or Rebels or other LEDs near 90 - 100 lumens per watt in an appropriate color mix (50/50 cool white and blue) run at 700 mA.

Where are you getting your kits? What do they contain for parts?

[Doahh]

8 gallon Biocube... with 60 degree lenses will 16 Cree XR-E LED's (4ledsx4leds mounted evenly on a 10"x7.2" area) would that be bright enough for all SPS corals? I'm putting this together as the retrofit Metal Halide light runs in the $320 to $400 range and the LEDs could be completely set up and dimmed for $275.

[der_wille_zur_macht]

16 will be plenty on an 8 gallon biocube. Go look at a certain popular nano forum, many people are using 12 LEDs on 8g biocubes.

IMHO, especially on a smaller tank where the cost difference isn't much, you are better off with too many LEDs run at a lower current than only a few run full blast, so you should be good.

[Doahh]

I'm going to run the Meanwell Dimmable ballast... it will drive them at 1kMa at full blast.

[Doahh]

Oh what Optics should I get to avoid the spotlight effect yet still be able to grow SPS at the middle/bottom of the tank?
I was thinking the 60 or 80's. By the way I'm ordering from RapidLED.com

[GeeTen]

Will the temperature be too high?:confused:
- aluminum box 130mmx100mmx33mm, cover removed
- 3 x White Cree Q5 XR-E Star LED (@1000mA)
- 3 x Cree Royal Blue XR-E Star LED (@1000mA)
I plan to glue the LED's with Arctic Silver Premium Thermal Adhesive
The sides of the box will be closed with aluminium plates and I intend to fit a plexi splashguard to protect the LED's, so it will be quite enclosed.

The picture is not to scale. The gaps between the stars might be more or less

Please give me some ideas on how to reduce the temp, in case you think I need to.

[der_wille_zur_macht]

Doahh,

Check specs on what you're getting, I know rapidLED used to sell non-dimmable ballasts and lower-bin XR-Es with their kits. You'll have a dense enough LED spacing that 20 or 40 degree optics should be fine, though you may find you don't need them. 1A drive is gonna be a lot for that many LEDs on a tank that small.

GeeTen,

6 LEDs are gonna make a lot of heat for a piece of metal that un-massive. A good cooling fan, and/or additional heatsinking would probably be a good idea. Can you at least get a box that's got fins molded on the outside?

[GeeTen]

I would consider placing a VGA or CPU heatsink with fan on top of that in case that I will get high temperatures. I am looking at the estetics of the build as well, because this will sit on top of the tank.

What should I consider as a high temperature? Anything which becomes un-touchable with the bare hand?

[wesley6610]

GeeTen, do your best to remember that what you are investing in should be functional first and look good a close second. Getting a quality heatsink with optional fans that protects your LED's and investment should be key. You can make a good enclosure/canopy that returns the "look" you are going for over your tank.

[GeeTen]

GeeTen,

6 LEDs are gonna make a lot of heat for a piece of metal that un-massive. A good cooling fan, and/or additional heatsinking would probably be a good idea. Can you at least get a box that's got fins molded on the outside?

Did a mock-up cardboard model and realised the temp will rise also with additional heatsinks. Decided to go ahead with 3 Cree's on each 130mm x 100 mm piece.
Just ordered the parts today, so I'll have time to consider and reconsider the next 2 weeks untill they arrive.

[ejg001]

Oh what Optics should I get to avoid the spotlight effect yet still be able to grow SPS at the middle/bottom of the tank?

If the tank is shallow, I would go with the 80 degree. Yupgopotty mentions that with the 40 degree optics he gets the spotlight effect on his 15R, which is 12" high.

What would you recommend Yup?

Will the temperature be too high?

The temperature will be too high. You'll need a heatsink with a fan. I built a small light for a friend with 6 CREE LEDs @ 700mA and it ran hot without active cooling. When I let it run for ~15 minutes without the fan, it got almost too hot to touch. The heatsink was about 5"x3"x2". I thought 2" fins would be enough to passively cool the LEDs, but they were not.

It is to be noted however, after a fan was put on top of the heatsink, the temperature fell to match room temperature. The fan was just an 80mm computer fan running off of a 5v wall wart. Running the fan at 5V instead of 12V kept it silent.

[wesley6610]

What's the estimated lifespan of Cree LED's with good cooling driven @ 700mA vs. 1000mA does anyone know?

[ejg001]

...Then in this thread, there were a couple postings that said do a 1xLED:1xGal ratio. I do plan on using 40deg lenses so I guess 48 should be fine.

With LEDs, it shouldn't be too hard to add in an extra set if you aren't happy, so I think you are making the right choice. Order 48 and if you need more, just move everything around to accommodate the extra light!

[wesley6610]

I initially choose to use 40 degree optics, but got an intense "spot-light" effect on the sand bed that my clam loved, but left other corals severely under-lit. What depth is your tank again and do you need intense light penetration all the way to your sand bed?

[ejg001]

What's the estimated lifespan of Cree LED's with good cooling driven @ 700mA vs. 1000mA does anyone know?

"Lifespan" is a tricky word with LEDs. Just because you reach 50,000 hours, they don't burn out or anything. They just output less light. Also, since 50,000 hours = 5.7 years, and over 11 years at 12 hours a day, I doubt anyone has run their own set of LEDs long enough to determine the effect of running at 700mA vs 1000mA.

Cree defines XR-E lifespan as the LED still producing at least 70% of its rated output after 50,000 hours of use @ 700mA.

From page 10, 1st paragraph: <a href="http://www.cree.com/products/pdf/XLamp7090XR-E.pdf">Cree XR-E datasheet</a>

"Cree projects that white XLamp XR-E LEDs will deliver <b>median</b> 70% lumen maintenance after 50,000 hours of operation at a forward current of 700 mA." This is with junction temp below 135C (275F) and ambient air below 25C (77F)

"Cree projects royal blue, blue, green and white XLamp XR-E LEDs to maintain a <b>mean</b> 70% lumen maintenance after 50,000 hours." This is with LED junction temp below 90C (194F) and ambient air 85C (185F) or below

It is interesting to note, depending on LED junction temp and ambient air temp, Cree switches up their statistical words. Cree uses the statistical word <b>"median"</b> 70% lumen maintenance for junction temp below 125C and ambient below 25C, whereas for junction temp at 90C and ambient at 85C, they use the word <b>"mean."</b> Median is the average, so assuming a gaussian, or normal distribution, after 50,000 hours 68% will produce lumen output within 1 standard deviation of each other, and 96% will produce lumen output within 2 standard deviations of each other. The mean is simply the middle number of a list. So, say you 24 LEDs and after 10 years, they produce 80,100,<b>102</b>,102, and 120 lumens, the mean is the number 102, because it is in the middle.

What does all this mean? (no pun intended) I suppose it means as ambient approaches junction temperature (85c ambient, 90c junction), LEDs may have the potential to have some pieces that drop off significantly more in terms of output over time, thus the switch to the word "mean." However, if ambient and junction are far apart (25c and 135c), which entails good cooling, you see a more uniform distribution. Based on the datasheet, you can't really draw a conclusion, but CREE does say that 1000mA is the maximum power for these LEDs.

I guess the only way to get any useful information would be to measure junction temp. Junction temperature would be the temp where the base of the LED touches the star -- i don't know of anyone measuring this yet for LEDs at 700mA or 1000mA.

[wesley6610]

Thanks, that is exactly what I needed to know. So then my question is as follows: I have seen many people running the cool whites @ 1000mA and the blues @ 700mA; should we assume that array's may need replacement sooner than the specs suggest because of this mixing/matching of currents?

[kcress]

ejg001; Excellent info. Thanks for that effort/write up.

wesley; No one can say. As each case is different. All you can do is look at your setup and ask yourself if it will still be adequate when the light has dropped off 30%.

If not, you need to consider using 130% of your original setup and then turning it down at the start. Then, as time goes by you turn it up. Alternatively consider replacing the LEDs in the future.

The good thing about future replacement is that in the future LEDs will probably cost about 1/2 what they do now.

[arredondojason]

so if I used 60 degree lenses instead of the 40 degree lenses then that would give me more spread right i have 3 350W MH on my 240 Gallon tank right now and want to replace each of them with 28 leds 1 to 1 ratio for each MH. do you think this is a good idea or what.

[arredondojason]

or should i go with the 80 degree lenses.

[der_wille_zur_macht]

That would be only 84 LEDs on a 240. If you are doing fish only, go for it. If you want corals, you'd be at about half the "average" density people are doing. Though, there are precious few examples of tanks that big with LEDs at this point in time.

And I'd go with 60 degree optics, if your LED count is on the low side.

FWIW, I'm going to start construction soon on a ~240 tank (5' x 3' x 2') and will likely be using 160 LEDs (20 strings, 8 each, in 3 banks of 6 strings each, plus an additional two strings for "accent" lights.) I will likely be using 40 degree optics, and 700 mA drive current. Basically, I am considering 48 LEDs, at 700mA, with 40 degree optics, to be equivalent to a really strong 250w MH or a weakish 400w MH.

I am basing this design on extrapolating from what other people are doing so far, and honestly have no solid experimental basis.

[arredondojason]

i have the same tank size lol.
ok well i am running a tek T5 light with 8 bulbs with individual reglectors on the front half and then runing 3 250W MH system on the back half where the rock is at.
i am wanting to replace just the MH and i have 2 euro bracings in the tank so i would run one set of 36 the Q5s in the center of each one of the braceings.
dose this make sence or just sound retarded.
i am new to the whole DIY LED lighting and have done so research so any help would be great.

[arredondojason]

bump for an awnser. thanks.

[wesley6610]

It does make sense, however, what I have found with my tank is that 36 LED per array is good coverage, but creates some shadows on the edges; coral placement will need to be considered. I have some dark spots on the backside of where my acro and monti are towards the left side of my tank; I believe that my arrays are centered over the opening as best that I could measure. However, on the right side I have decent coverage on my orange monti cap...so just keep in mind coral placement and the use of optics will narrow your spread of light on the sides.

http://i849.photobucket.com/albums/ab55/wesley404/9-24-2009/DSC01880.jpg

[saraiva]

Hey guys, any comment on blue Cree led from http://www.dealextreme.com/details.dx/sku.1775 ?

[wesley6610]

It's hard to say what the deal is with this "blue" LED, there is no information on it like they have for the Q5 cool white stars. Buy with caution is my suggestion.

[saraiva]

Hey guys, any comment on blue Cree led from http://www.dealextreme.com/details.dx/sku.1775 ?

[der_wille_zur_macht]

Replied in the other thread. It's very likely a total waste, I would avoid it.

[yupgopotty]

If the tank is shallow, I would go with the 80 degree. Yupgopotty mentions that with the 40 degree optics he gets the spotlight effect on his 15R, which is 12" high.

What would you recommend Yup?


I think you'd have to go pretty wide on a shallow tank, I'd say the 80 sounds about right. Either that or no lenses at all.

[wesley6610]

+1

40 degree would be too much on a shallow reef

[bluetang_2000]

very interesting discussion. Tagging along

[yupgopotty]

It does make sense, however, what I have found with my tank is that 36 LED per array is good coverage, but creates some shadows on the edges; coral placement will need to be considered. I have some dark spots on the backside of where my acro and monti are towards the left side of my tank; I believe that my arrays are centered over the opening as best that I could measure. However, on the right side I have decent coverage on my orange monti cap...so just keep in mind coral placement and the use of optics will narrow your spread of light on the sides.


Wesley, sorry if you mentioned this before but how many gallons is your tank and how deep is it? What lenses if any are you using?

[wesley6610]

Never an issue...my DT is a standard 75 gallons @ 20" before sand, so it's more like 17 - 18" with my sand bed on average. I ordered 40 degree optics, but found the that light penetrated TOO much and I had columns of light on a shallow reef. So I removed all except those near the cross brace and the spot-lighting is gone. I kept those close to the cross brace on to prevent scatter/absorption and to squeeze most of the light past the edge and into the tank.

http://i849.photobucket.com/albums/ab55/wesley404/10-3-2009/DSC01887.jpg

[yupgopotty]

So are you using 2 x 36 LED arrays? I'm just curious because I'm using 24 LEDs on my 15 gallon, and that doesn't feel like overkill but in comparison it sounds like it.. I'm thinking of getting a larger tank in the 60g range, so I'm trying to figure out the best number of LEDs to use (was leaning towards 72 but who knows)

As for the lenses, my 40 degree had a spotlight effect as well in the top and middle of the tank. It wasn't so bad near the bottom but I've taken the lenses off anyways.. I might go with a 60 or 80 degree next time.

[wesley6610]

Yeah, I have 2 x 36 arrays with a 1:1 ration of white to blue. When I was designing my arrays I looked at Soundwave's and figured with all the extra space on his array, at least 12 more LED's could fit and I could just drive them @ 700mA if it was too bright. I'm glad that I went over, since I have shading on the edges even w/o the lenses. Next time I will have longer arrays and push about 96 LED's w/T5's for added coloration and allowance for me to not use optics.

If I did use optics, I would have to have a fairly deep tank and be looking to keep a large clam or something on the sand floor in that case. I just ordered some Pocilliopora (sp) frags and will start them out at the bottom and move up to make sure the lights aren't too strong.

[PruneHands]

I moved 2 years ago and had to dismantle my reef setup. :sad2: I have missed it ever since. I am working up a new and improved (bigger) setup that I plan to incorporate LED's into. I had a DIY moonlight system that used LED's on my last MH canopy and some of the connectors/wiring I used became corroded over time. Does anyone know how the supporting electronics used in the LED systems described in the great RC threads hold up in the marine-air environment ?

[g8gxp]

I moved 2 years ago and had to dismantle my reef setup. :sad2: I have missed it ever since. I am working up a new and improved (bigger) setup that I plan to incorporate LED's into. I had a DIY moonlight system that used LED's on my last MH canopy and some of the connectors/wiring I used became corroded over time. Does anyone know how the supporting electronics used in the LED systems described in the great RC threads hold up in the marine-air environment ?

I think as long as you take the proper precautions there shouldn't be a problem with the electronics. Splash guard is a must, the driver housings are pretty well made so I don't think there will be a problem with those, especially if you put them in a project box. I have also heard to coat any exposed wire ends with clear nail polish.

[wesley6610]

you could also use thermal shrink tubing for a moisture proof seal of the wires, but a splash guard would be the best for covering the LED's. i don't have a guard personally because my arrays are about 6 - 8 inches off the water line, i haven't yet noticed any salt creep or splashing. in the event some occurs, i will use a guard, but not a full one, but just over the LED section of my canopy.

[ejg001]

Hi guys,

Haven't been around much, but Wesley, I like your LED setup. Looks great!

I have a bunch of sample LEDs from various mfg. and places. I'm going to try to do a write up / analysis of them to see what the best place to buy them from is. We'll see where it takes us! Hopefully I'll be done by the time the weekend is over. I may do a new post, because it isn't really on topic. Just FYI.

[wesley6610]

Thanks ejg001, I put a lot of time and work into it for sure. I've found that 72 LEDs @ 700mA is a tad too much...I readjusted the current down to 500mA and will observe over the next two weeks or so.

[yupgopotty]

Wesley, are you using CREE Q5's? I'm just curious because if you're turning them down to 500ma, then maybe Q4's at a slightly higher ma (maybe 550 or 600ma) might give the same number of lumens as your Q5's at 500ma. This might be better financially for anyone looking to buy now since the price between Q4's and Q5's is about $2 each right now.

[Canoe]

Photo Colours Not Showing Accurately:

as mentioned in your posts, the photos don't show the true colour of the LED light. yupgopotty with your Canon Rebel XT and wesley6610 with your Sony W-80, the EXIF data within the .jpg files show that your camera's White Balance is set to AUTO. This means that the software in the camera adjusts(skews) the colours to try to get a good White Balance, which is impossible with such a homogeneous biased colour source provided by the LEDs. I'm not familiar with your camera's specific settings, but to record much more accurate colours you need to set your camera's White Balance manually. You want it to record at 5000K, which on your camera may be Off, Daylight, 5000K, or you may be stuck going for the closest actual degrees Kelvin setting, be it 5700K (typical for camera flash), 6000K, 6500K or 6800K. Closest to 5000K will give the most accurate results of what the LED arrays are actually putting out.

In addition to recording accurate colours, for pleasing photographs of the contents of the tank, try various manual settings to get a pleasing rendering balancing the "blue" bias of the light to the "actual" colours of the subjects in the tank. While not technically accurate or true colours, you should be able to find a manual White Balance setting that renders the same look & feel you get when standing there in front of the tank, thereby locking into 2 dimensions a colour rendering that re-creates (well, as close as you can get) the same look & feel that you perceive live.

[kcress]

Canoe; Thanks for chipping in.

Why does a 5000k setting typically render better truth to LEDs?

Would a typical WB correction done with a white piece of paper provide any benefit with tank photos?

[Canoe]

...
Would a typical WB correction done with a white piece of paper provide any benefit with tank photos?

For Photographing Subjects

Humans' perception of colour is relative and variable. When humans are viewing something live, our minds automatically try to adjust our colour perception such that things we believe are white "look" white. The camera's sensor's measure of colour (light) is not variable, it is absolute. The white balance adjusts the measured colour values to match them to values that we will perceive as "correct" and those values are recorded; in that, an object that is white in real life will appear white in the image. (For practical reasons, we'll ignore how the sensors get file RGB values.)

Recall snow in winter on a sunny day: snow in shadow lit by blue sky (10,000K) appears blue, in full sun it's yellow (3,000K), in between there's a point where the yellow light from the sun balances the blue light from the sky (5,000K) and we get snow that appears white. With WB on auto, zoom in such that you're only photographing snow lit by one condition and the image will have white snow. Get a shot with all three light conditions on the snow and you'll get snow of all three colours with blends in between.

A WB calibration with a piece of white paper (is it realy "white"? or will it skew the calibration) will match the WB adjustment to the light colour values that either bounce off or transmit through (different methods) the paper. Paper is not a good "through" material. This adjustment will make the blended light look "white", therefore the light is now effectively "white" and hence colours should record correctly.

This works if the light falling on the paper is the same light that is falling on the subject. So, if you can get the paper inside the tank to the position you'll be photographing you'll get the same light as will fall on the subject... If you have to get the subject colours right, perhaps you can laminate a board with white, 18% grey and a MacBeth Colour Chart on it for both exposure and colour balance correction, but temporarily replacing the tanks lighting with several 5000K fluorescents with a high colour index would provide better results. If you can get flash intensity sufficiently brighter than the tank's lighting, such that only the flash intensity counts, the flash colour temperature is usually around 5700K, considered close enough, or you can calibrate to your flashes and have a standard correction to do to the resulting image file. A flash has the added advantage of freezing the action, and with various light modifiers (reflectors & such) you can control the specularity of the light as well.

By manually trying different WB values, you can get one that will provide the most pleasing rendering of the colours of the subjects within the tank while under the tank's lighting. Assuming your camera can be adjust so, (and for accuracy) start with the colour temperature of the lights (i.e., 16,000K). One of the difficulties is that the light within the tank is a mix of the light from the canopy source and any ambient room light outside of the tank (assuming it's bright enough to matter). So, depending on the tank's lighting, and the room light at that time of day, you could get in-tank photography light WB changing throughout the day.

Blue LEDs are not a broad spectrum light source. Good luck getting a colour balance or any sort of good colour rendering. White LEDs have a broader spectrum and you should be able to get a reasonable WB, but a manual setting will give consistent, and adjustable, results.

[Canoe]

...
Why does a 5000k setting typically render better truth to LEDs?


To judge colour, our perception is relative. So to judge a light being more or less blue, it's more or less blue than what? Another light source present? Is that light white or off-white or another shade of blue?

To have a place from which to perceive different colours being more blue, yellow or whatever, we use the standard of comparing it to "normal" daylight. By convention, this is 5000K. So if your camera's WB is manually set to 5000K, the image will record how blue, or purple, or yellow, the light is. And easier to do so if it's shining on something that is actually white, not off white or a colour.

So a photograph of a tank with a 5000K WB will provide as accurate as possible rendering of the resulting light, as is possible with an RGB (red, green, blue) recording. Different camera sensors do better/different jobs at this than others, but we're not trying to provide either an absolute colour measurement nor a full-spectrum analysis using an RGB image file.


To get really interesting with LED lighting qualities, we have to compare them to MH fixtures with their reflectors that provide tanks with light specularity similar to what we get from the sun. From the bulb filament we get the brighter & harsher direct illumination light and its detail providing well defined shadows (gives that great shimmer effect in the tank). From the reflector we get "fill light" (fills in the harsh shadows from the prime "sun" light) that imitates the indirect ambient light that comes from the sky.

With the LED lighting, we get shimmer in the tank, from the highly specular LEDs, but each LED provides it's own shimmer underneath it, with spill from surrounding LEDs providing the fill or ambient light.

So, MH gives shimmer like from the sun. LEDs act like many little suns spread out above the tank (each with its own shimmer)...

P.S. I'm thinking of an additional row of small lower power UV LEDs along the front of the tank, pointing downwards and towards the back, just to pop the fluorescing colours. This may aid some coral's growth, but I don't know if it would be safe/healty to corals to leave them on 24/7. And there should be something to shut them off when you open the hood so you don't expose your or other's eyes to UV.

[kcress]

Canoe; Thanks for the WB lesson. Most appreciated. Maybe now we can get some truer pics of these LED based well lit tanks.

[wesley6610]

Wesley, are you using CREE Q5's? I'm just curious because if you're turning them down to 500ma, then maybe Q4's at a slightly higher ma (maybe 550 or 600ma) might give the same number of lumens as your Q5's at 500ma. This might be better financially for anyone looking to buy now since the price between Q4's and Q5's is about $2 each right now.

Hey, yeah, I'm using Cree Q5's and I found that with about 6 - 7 inches from the water line that 700mA is too much even for my SPS....so I have had them turned down to about 505mA and they seem to be coloring back up nicely. However, if someone has a 90 gallon, they may need to have them turned up to 700mA to get good light at the bottom. I have a clam and sps on the sand level that seem to be getting bleached initially. I have some Poci mounted halfway up, but they seem to be the only ones not affected too much by the LEDs when they were turned up!

:dance:

[der_wille_zur_macht]

Wesley, are you using CREE Q5's? I'm just curious because if you're turning them down to 500ma, then maybe Q4's at a slightly higher ma (maybe 550 or 600ma) might give the same number of lumens as your Q5's at 500ma. This might be better financially for anyone looking to buy now since the price between Q4's and Q5's is about $2 each right now.

Thing is, with a ~10% difference in efficiency, the Q5's will pay for themselves after a few years, and you'll be saving money after that. Maybe not a huge consideration if you are building a smaller tank or one you don't expect to last a long time, and/or are trying to keep upfront costs down, but something to think about.

[barderer]

it seems it would make sense to lay out the LEDs in rows of the same color instead of alternating colors on the same row. Since you view the tank perpendicular to the output of the lights. Hence, the colored spotlight effect would be reduced because you would be seeing a blend of uniform layers instead of alternating layers.

[yupgopotty]

For me personally I just wanted to distribute the light as evenly as possible. I didn't really take into consideration what the color spectrum would look like to me. If you aren't using lenses I'm not sure if the set-up really matters all that much anyways.

[Canoe]

it seems it would make sense to lay out the LEDs in rows of the same color instead of alternating colors on the same row. Since you view the tank perpendicular to the output of the lights. Hence, the colored spotlight effect would be reduced because you would be seeing a blend of uniform layers instead of alternating layers.

Actually, that makes the light attribute you're trying to hide (blend) bigger, which makes it more noticeable.

For maximum blending, you'd have to have a blue and a white mounted side by side as close as possible and then space out these pairs, and without lenses.

Colour Spectrum:
Cree publishes graphs of the colour spectrum, but the y scale is a relative percentage of the peak output maximum. This doesn't allow us to compare light output between the different LED graphs. So summing the curves to give a best-guess of the resulting colour spectrum is very much a guess.

Also, has anyone taken a look at the projected light of a single white LED and checked to see if the colour is consistent throughout the angle of coverage or if the colour changes from center to edge?
Anyone have a photo of this? (with Colour Balance set to 5000K? ;-) )

[Canoe]

How much of the LED light spills directly from the LED out of the tank?
As in, how much does the tank's glass side reflect that light back into the tank?

[yupgopotty]

canoe, i'm not sure how you would measure that. But it would obviously depend on how far from the ends you are placing the LEDs, and if you were using lenses or not. If you're worried about "losing" or "wasting" light through the sides of the tank, then you can put some lenses (20-40 degrees) towards the ends so the light is directed down into your tank and not out the sides.

[der_wille_zur_macht]

Check the datasheets for the LEDs you are interested in. Most show graphs of the light spread, which you could use to get a rough idea.

IME though, even with LEDs that have a wide spread and no optics, the light "lost" is going to be less than with other popular forms of lighting for reef tanks.

[PJchicago]

Hi guys, I am doing a good size LED array and I am starting to get into the electrical end of things and have a few Q's. First off, thanks to everyone for all the info that has been shared thus far, I could never have gotten this far on my own.

Tank is 72x24x24. Doing 148 LEDs, 72 CW Q5, 72 RB Q5, and 4 UV. I am attaching some pics, but the were taken from my cell phone and are a little fuzzy. Using the meanwell pwm dimmable drivers and 6 12 x 18 heatsinks. Using optics on all, moving from front of tank to back I have lengthwise rows of 40, 60, 40, 80, 60, 80. this accomodates full depth at front and shallower back. LEDs also slightly closer together for front of tank.

Vendors were rapidled and heatsinkusa. Using 3 of the rapidled prepackaged 48 LED DIY kits. Both vendors were very good, would reccommend both.

One tip I can share that I have not seen mentioned here yet is silver conductive epoxy instead of soldering. Little expensive, but not really if you don't already have a soldering iron. I mounted the stars on the heatsink prior to soldering using the artic silver thermal adhesive. I then had a very difficult time soldering. I just could not get the connections hot enough. Watched videos on youtube on how to solder, etc, but still could only manage very sloppy connections. Practiced away from the heatsink and it went fine, so I think the issue was the heatsink / adhesive doing their job, but making mine very difficult. So I found this conductive epoxy and used it for the solder joint. no cance of heat damage to LEDs and all connections worked perfectly.

http://cableorganizer.com/mg-chemicals/silver-conductive-epoxy.html?engine=google&s_kwcid=TC|6214|silver%20conductive%20epoxy||S|e|2977216215&gclid=CKmE5NLX8Z0CFSUMDQodXSXeOw

That is where i actually ordered from and I could have done my whole array with 2 packages for about $50. I was more than happy to pay that to escape the soldering. I precut all wires and crazy glued so wires were touching the pads on the stars on both ends. You have about 5 min of working time once mixing the epoxy. I mixed 1 mm of each part and applied to connection with a toothpick. I was able to do one full heatsink of 24 LEDs per 5 min of each mixing.

On to my questions:
For the meanwell pwm dimmers, I do not have a pwm dimmer yet, can I bypass this by just hooking up a AA battery to the two wires? Seems to work when I test with multimeter.

I am not sure what I am reading on the multimeter- instructions that came with it are very sparse. I can see 48V when I bypass the dimmer leads with a battery, but I am not sure I am reading ma correctly. It only has a switch forvoltage and resistance with the little upside down horseshoe symbol. Resistance reads .8 , would this indicate 800ma?

I thought the meawell was ok to drive anywhere from 1 to 13 3w LEDs. I did a test hookup on a full 12 LED string and it seemed to work ok, I then tried to connect just one LED and I blew the LED. what would be the minimum amount of LEDs, or what did I do wrong here?

I want to hookup the whites and blues seperate so I can dim seperately. I have 12 drivers total, six for each. Is it ok to wire each group of six drivers to one plug that goes to the wall?

Can the reefkeeper lite controler act as a pwm dimmer?

Thanks for any assistance / insight in helping me get this up and running. I am sure I will be back with more Q's as I get into this.

[PJchicago]

some pics...

[wesley6610]

PJchicago, great LED build and I will try to answer the parts I'm familiar with. The meanwell can drive 1 - 13, but if you are driving just one, you need to adjust the current and voltage down. The voltage of the LEDs is about 3.7 and the driver is rated at 48V, so you blew it with like 10 times the rated volts. As for the multimeter, I would suggest getting a better meter that does volts, amps, resistance etc to make sure you are reading everything precisely as your adjustments will need numbers to compare apples to apples with others trying to help you trouble shoot!

[james3370]

PJchicago, great LED build and I will try to answer the parts I'm familiar with. The meanwell can drive 1 - 13, but if you are driving just one, you need to adjust the current and voltage down.

if i'm not mistaken, the meanwell won't turn down low enough to power just one LED.....according to the spec sheet (http://www.trcelectronics.com/Meanwell/pdf/eln60.pdf) the "output voltage adjustable range" on the eln-60-48 is 43.2-52.8v

[wesley6610]

I stand corrected, thanks James!

[der_wille_zur_macht]

So I found this conductive epoxy and used it for the solder joint. no cance of heat damage to LEDs and all connections worked perfectly.

I've never used that and am not sure of the viability - maybe one of the "real" EE's can comment? FWIW, you said it cost you around $50. For that much, you can get a decent soldering station and have at it. I'm willing to bet that your soldering difficulties were due to an underpowered or poorly controlled iron.

For the meanwell pwm dimmers, I do not have a pwm dimmer yet, can I bypass this by just hooking up a AA battery to the two wires? Seems to work when I test with multimeter.

I don't have the datasheet in front of me, but a driver like that with a PWM dimming circuit is basically going to register "on" at anything above a certain threshold voltage. So as long as your battery was above that voltage, it would be fine to do that. Also check the datasheet for a max voltage on that connection.


I am not sure what I am reading on the multimeter- instructions that came with it are very sparse. I can see 48V when I bypass the dimmer leads with a battery, but I am not sure I am reading ma correctly. It only has a switch forvoltage and resistance with the little upside down horseshoe symbol. Resistance reads .8 , would this indicate 800ma?


Have you actually wired the driver to your LEDs? I wouldn't bother trying to measure the output side of the driver with no LEDs wired in - a constant current driver is basically going to max out in one direction or the other (depending on if it's boost or buck) if you turn it on with nothing on the output.

I thought the meawell was ok to drive anywhere from 1 to 13 3w LEDs. I did a test hookup on a full 12 LED string and it seemed to work ok, I then tried to connect just one LED and I blew the LED. what would be the minimum amount of LEDs, or what did I do wrong here?

Again, check the datasheet. The driver probably has some minimum voltage it can cut down to. And speaking of that:

if i'm not mistaken, the meanwell won't turn down low enough to power just one LED.....according to the spec sheet the "output voltage adjustable range" on the eln-60-48 is 43.2-52.8v

James, you're basically reading the adjustability for the MAX end of the voltage range. It can run under those numbers, but there may be a true minimum. Or, the OP could have wired something wrong. . .

I want to hookup the whites and blues seperate so I can dim seperately. I have 12 drivers total, six for each. Is it ok to wire each group of six drivers to one plug that goes to the wall?

Depends on your wall outlet's circuit and the plug you're using. Six of these drivers is going to be about 300 - 350w, or around 3A at 120V AC. Assuming your wall outlet, the plug, and the wiring you are using can handle that, you should be fine.


Can the reefkeeper lite controler act as a pwm dimmer?


Not by itself. I think they're coming out with a PWM or variable DC module for the Apex, but I don't know if it'll work with the RKL. I'd suggest you ping the vendor. Worst case, they say no, but then they also know that people out there want that featureset.

Another general comment for you - figure out that ammeter functionality on your multimeter fast! The driver you are using is capable of up to 1.3A, which will cook your LEDs in no time. So it's important to know what you're running them at.

[der_wille_zur_macht]

if i'm not mistaken, the meanwell won't turn down low enough to power just one LED.....according to the spec sheet (http://www.trcelectronics.com/Meanwell/pdf/eln60.pdf) the "output voltage adjustable range" on the eln-60-48 is 43.2-52.8v

Some further comments about this, because it looks like there is some confusion.

Constant current LED drivers basically work by monitoring the current on the output circuit, and adjusting the output voltage to maintain some ideal current.

Hence, the voltage on the output side will depend on the load (i.e. if you have 6 LEDs vs 3, the current will remain the same, but the voltage will double).

In other words, the voltage will vary considerably from one implementation to another for the same driver - the driver doesn't have a set output voltage.

However, drivers DO have a range of output voltage they can supply. This basically translates into a minimum and maximum number of LEDs, for an LED with a given voltage drop.

Looking at the datasheet linked above, the number we want is "LED OPERATION VOLTAGE" which is 3 - 48 for this driver. As long as the sum of the forward voltages for the LEDs you are using falls in that range, the driver will be able to maintain a constant current, and correctly drive the LEDs.

If the forward voltage of your LED string is less than that, you'll cook the LEDs (the driver can't "turn down" the current low enough). If it's higher, you'll underdrive the LEDs.

So the minimum for this driver is 3v, according to the datasheet. These LEDs can handle 3 volts just fine, so I'd wonder if either the driver was out of spec (possibly due to fiddling with the two internal adjustments?) or the LED was damaged some other way, or wiring was faulty.

[james3370]

me & my spec sheet reading sometimes.......http://img.photobucket.com/albums/v501/james3370/smileys/doh.gif

[Hesham]

One tip I can share that I have not seen mentioned here yet is silver conductive epoxy instead of soldering. Little expensive, but not really if you don't already have a soldering iron. I mounted the stars on the heatsink prior to soldering using the artic silver thermal adhesive. I then had a very difficult time soldering. I just could not get the connections hot enough. Watched videos on youtube on how to solder, etc, but still could only manage very sloppy connections. Practiced away from the heatsink and it went fine, so I think the issue was the heatsink / adhesive doing their job, but making mine very difficult. So I found this conductive epoxy and used it for the solder joint. no cance of heat damage to LEDs and all connections worked perfectly.

http://cableorganizer.com/mg-chemicals/silver-conductive-epoxy.html?engine=google&s_kwcid=TC|6214|silver%20conductive%20epoxy||S|e|2977216215&gclid=CKmE5NLX8Z0CFSUMDQodXSXeOw



I would be careful with the use of conductive epoxy to replace soldered connections. The resistance of the material you chose is about 0.38 ohms/cm. Assuming about 1A current for your array, a minimum of 20 gauge wire is required (and frankly, I would use 16 gauge for safety and temperature derating). 20 gauge wire has a resistance of about 0.0003 ohms/cm.

This means that there is a much greater resistance in the connection using the epoxy vs. using a wire (for this discussion I assume solder connection has similar resistivity to the wire - I am cheating a little here).

End result is that the connection points with the epoxy will run much hotter than if you were to use solder. This heat will be transfered into the LED, LED substrate, heat sink, and the wires. Be careful that the wires do not overheat and cause the insulator to melt. I don't know if this would be a fire hazard but please take caution.

[PJchicago]

I would be careful with the use of conductive epoxy to replace soldered connections. The resistance of the material you chose is about 0.38 ohms/cm. Assuming about 1A current for your array, a minimum of 20 gauge wire is required (and frankly, I would use 16 gauge for safety and temperature derating). 20 gauge wire has a resistance of about 0.0003 ohms/cm.

This means that there is a much greater resistance in the connection using the epoxy vs. using a wire (for this discussion I assume solder connection has similar resistivity to the wire - I am cheating a little here).

End result is that the connection points with the epoxy will run much hotter than if you were to use solder. This heat will be transfered into the LED, LED substrate, heat sink, and the wires. Be careful that the wires do not overheat and cause the insulator to melt. I don't know if this would be a fire hazard but please take caution.

Thanks for the information. I did use 16 gauge for the whole thing, I will monitor closely and run fully supervised untill I see how it all works together.

[PJchicago]

So the minimum for this driver is 3v, according to the datasheet. These LEDs can handle 3 volts just fine, so I'd wonder if either the driver was out of spec (possibly due to fiddling with the two internal adjustments?) or the LED was damaged some other way, or wiring was faulty.

der_wille_zur_macht, thank you for your responses, very helpful. I tried both a 40w and 100w soldering iron. I have no doubt that my inexperience with soldering is largely to blame.

Looks like it is time for a better multimeter. I did open up the meanwell, but no fiddling (yet) untill I get a handle on the multimeter.

[der_wille_zur_macht]

der_wille_zur_macht, thank you for your responses, very helpful. I tried both a 40w and 100w soldering iron. I have no doubt that my inexperience with soldering is largely to blame.

Looks like it is time for a better multimeter. I did open up the meanwell, but no fiddling (yet) untill I get a handle on the multimeter.

It's worth noting that even powerful soldering irons can be hard to use if they don't have good control - you'll hit really hot and really cold over and over again, instead of holding an ideal temperature. Tinning, how you hold the tip against the parts, the solder you're using, and other factors all come in to play. It's probably one of the hardest soldering projects for a newbie to tackle, no doubt.

If you're going to run the LEDs before you get another multimeter, I would suggest finding the pot that controls max current and turning it all the way down. I don't know how the pot comes set from the factory, but if it's more than about halfway to the max (~1000mA), you'll start killing LEDs.

[kcress]

I thought the meawell was ok to drive anywhere from 1 to 13 3w LEDs. I did a test hookup on a full 12 LED string and it seemed to work ok, I then tried to connect just one LED and I blew the LED. what would be the minimum amount of LEDs, or what did I do wrong here?


You hooked up the LED backwards. Since it is a diode it did not want to pass any current. The Meanwell... got, er, well, mean and continuously increased the voltage in a effort to reach its adjusted current level. This caused it to put out its maximum voltage against the LED's blocking resistance.

The maximum Reverse Voltage limit of those LEDs is 5V. If you exceed that the LED structure will catastrophically fail. It did. It would only take a fraction of a second too. It could flash. It wouldn't be due to the LED operating it would be due to the LED acting as a conventional incandescent filament - briefly. :fun2:

[tehfeer]

Do you guys think 24 lights be overkill for a 14g biocube? I am tempted to remove the PC lighting and install some DYI leds.

[der_wille_zur_macht]

I built an LED array for a 16g nano that had 24 LEDs, but did not run it long enough to determine overall effectiveness. Though, I can tell you from my brief experience that 24 LEDs on a tank that small borders on insanely bright. Like, the only thing that will not burn away to nothingness will be the most light-hungry corals you can get your hands on. If I were to do it again, I would probably aim for 18 at most.

This array was driven at 700mA and had no optics, FWIW.

[tehfeer]

Lol thanks for the tip man!

[saf1]

Hmm...wonder if 8 will be too much for a 6 gallon then? I picked up a super cheap marineland 6 gallon eclips system (tank/hood/filter) combo that I couldn't pass up to test LED's on before my new display tank.

I figured 1 meanwell, 4 white, 4 royal blue, and call it good. Plenty of room in the hood to mount everything neat and orderly. I was going to move 20 lbs or so of live rock and sand from my existing auto-pilot tank, with clowns and royal gramma. No coral so it would be perfect to start something from the get go once water was dialed in

Maybe I should just do 2 x 2 instead. I can't have anything growing crazy in there, but I'd like some green star's, maybe some of the pom pom xenia, and hopefully another elegance if I can find a healthy one. Hard corals no idea but this is for my desk.

[der_wille_zur_macht]

Well, I don't mean to scare anyone. :D You can always turn the thing down if it's too much, or take one or two LEDs out of the circuit. Though, it sounds like your coral ideas are all pretty low light, so 4 or 6 would probably be OK.

[saf1]

Oh no - I didn't take it that way :) Saving 20 to 30 bucks is also a plus. Can divert that money to the power head or a mini closed loop for water flow.

I'm liking the idea more and more now if truth be told. Meanwell driver, 4 or 6 led's - I'm thinking that is really affordable.

[der_wille_zur_macht]

If you'll be sticking with 6 or fewer LEDs, it would probably be a few bucks cheaper to use a buckpuck driver. Also likely more efficient, though both factors will depend on the power supply you use for it. If you can find an efficient DC power supply under $10-$15 it'll be a win-win situation.

[james3370]

If you'll be sticking with 6 or fewer LEDs, it would probably be a few bucks cheaper to use a buckpuck driver. Also likely more efficient, though both factors will depend on the power supply you use for it. If you can find an efficient DC power supply under $10-$15 it'll be a win-win situation.

i have bought several of these (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220443227884) wall warts from this seller. it's a 24v/1a wall wart for $2.99 + $5.99 shipping......but it comes from hong kong so it takes 1-2 weeks to get it

[saf1]

Reasoning behind the meanwells is it looked like it is all inclusive - i just need to add a power cord and off I go. My understanding with the buckpucks is that I need to add a power source as well. I may have one laying around depending on what is needed but I liked the idea of the meanwell a bit better.

Unless I missed something completely - which is very possible :)

Rapidled listed the Mean Well LPC-35-700W for 24 bucks. The CREE XR-E Q4 Cool White I think listed at 6 bucks a pop and the royal blues which I think are a bit different I guess for 7 bucks.

So just rough math looked like 25 for driver, 12 for 2x cool white, 14 for 2x royal blue. So total cost around 60 bucks maybe. Heat sink I'm going to see what I have laying around and same with wire, etc. Not sure though - but I need to order these couple of parts first so I can sort of see what I need next.

[saf1]

Thanks James - I actually have several power sources I believe laying around. Phone chargers and other small devices. What does the buckpucks take?

I guess one advantage is that the buckpucks are dimable from the get go?

[der_wille_zur_macht]

The buckpucks need at least 2 volts above the sum of your LED's forward voltage, and current capability at least 20 - 30% higher than your drive current.

If you are doing 6 LEDs at 700mA, that means roughly 24V and 1A.

Keep in mind that the buckpucks are only dimmable if you buy the dimmable versions. They are available without dimming, too. And depending on which dimmable version you get, it might or might not come with a wiring harness and a pot - so pay attention when you order.

[james3370]

Thanks James - I actually have several power sources I believe laying around. Phone chargers and other small devices. What does the buckpucks take?

I guess one advantage is that the buckpucks are dimable from the get go?

tha buckpuck will take up to 32v of input power.....input power is determined by how many leds you have in a "string". typical crees take 3.3-3.7v per led (depending on if you run them at 300, 750 or 1000ma), so say 6 @ 700ma (3.5v) is 21v (add a bit for headroom, so 24v)

this is the difference in the buckpucks & the meanwells....the buckpuck will only run about 8 leds, whereas the meanwells will run 12 maybe 13

buckpucks can be had in dimmable & non-dimmable versions....same can be said for the meanwells, but the dimmable meanwells are a "custom-order" so they can take awhile to get sometimes

**edit** combine what i said & what DWZM said since we both seemed to be posting at the same time LOL

[saf1]

Thanks - both of you. I like how you abbreviated DWZM's name, I was like...hmm...what part of that do I use :)

I think I'll just stick with the meanwell then since the same led store carries them all. So might as well stick to one place. I don't think I really need more than 6 leds probably - so either way it sounds like I'm covered.

Honestly - I just want to get my feet wet and see how it works, looks, feels etc. I need to take down my 100 gallon here in about a month or so and won't be able to store it. So I want my best piece of rock or two and the fish moved :) Then I'll plan out another 100 gallon or so with LED's.

If I can pull this off ok then I'll order a couple LED's every month to hide the cost. It seems to add up rather quickly when you start talking about covering 100+ gallons due to the number of LED's.

I like the 50 dollars or so right now - easier to swallow if you will when on a budget :)

[james3370]

keep an eye over on nano-reef.com as they occasionally do group buys on the LEDs & you can get the price per LED down a nice bit going that route

in fact, the ULTIMATE LED GUIDE (http://www.nano-reef.com/forums/index.php?showtopic=186982) thread over there is an awesome read on all the aspects of doing an LED fixture. also check out some of the links in Evil's sig (that thread starter)

evil over there is kinda like DWZM, kcress, grim reefer, etc here....the savant(s) LOL

also, the lighting section over there is a smorgasborg of different LED DIY builds

[der_wille_zur_macht]

Thanks - both of you. I like how you abbreviated DWZM's name, I was like...hmm...what part of that do I use :)



You can tell the people who frequent The Lounge by what they call me out here on the real forums. :lol:

[saf1]

I don't think I visit that forum.

I just didn't want to offend anyone :)

[giants]

I have some LEDs that are really bright. They are bright enough that you can't look directly at them. I was wondering if these could be used to build a day time light fixture for a tank if I had enough of them or are the LEDs you guys are using a different type that give off different lighting? The ones I have aren't packaged like the one that you are showing on this site. Mine look like a standard LED with the two lead coming out of it.

I ordered them out of a catalog call Electronics Express for $1.50 each. They have an angle of 55 degrees and are 8mm in diameter. The white ones say they have 16,000 luminous intensity mcd @100mA and the blue ones say 11,000 luminous intensity mcd @100mA. That is all the info that I have on them.

I made a set of lunar lights for my tank using 6 of the blue ones. I haven't put it on my tank yet, but it looks good projecting on the floor. I am running them with an AC adapter that I had that put out 9 volts and 200mA. I set them up in a combination of series and parallel so each LED is getting 4.5 volts and 67mA. I have them attached to a long thin piece of plywood. Does anyone see this being a problem/fire hazard? I ran them for 16 hours without turning them off and none of the LEDs got even a little hot.


What else would I need to know about them to see if they are Ok to use for Day time lights?

My tanks is a FOWLR system, but I may add corals down the road someday.

Thanks for any info.
Jason

[der_wille_zur_macht]

My tanks is a FOWLR system, but I may add corals down the road someday.

In this case, honestly, if it looks good to you, it's fine. Go ahead and put those LEDs on there.

Based on the rest of the info you gave, I wouldn't bother with those LEDs over a tank with coral - for just a few bucks more per LED, you can get something known to work. The variation in intensity at a given power level even between the best and worst bins of Cree XR-E can be 100%, so going with something relatively unknown is really a crapshoot. It's likely that the LEDs you have aren't as intense as they seem, since if they were, they'd probably be in a package with better heat dissipation than a standard through-hole LED.


I have them attached to a long thin piece of plywood. Does anyone see this being a problem/fire hazard? I ran them for 16 hours without turning them off and none of the LEDs got even a little hot.


If it's not getting hot, and the wood is protected from water (i.e. painted or coated with something waterproof) then it sounds fine for this application.

[giants]

Which LEDs and power source would you recommend? I see a couple different ones named on here. Also, do you have to purchase everything in a kit, or can you purchase everything separately? I assume that all I would need is the LEDs, a heat sink, and a power source. Could I get a piece of aluminum from Home Depot and drill holes in it for the heat sink, that’s all it looks like it is in the pics I’ve see?

Also, could you tell me how close you should place the LEDs to each other and how far the fixture should be from the top of the tank? This would be going on a tank that measures 90”x 36” wide x 28” deep if that makes a difference.

I would just like to add that this site is the awesome; there isn’t a LFS around here that knows enough to give out info like this.

Thanks again!

[der_wille_zur_macht]

Hey Giants, I see you're in Syracuse. That's practically my backyard. If you want firsthand help with your rig, lemme know.

Regarding your questions, the best LEDs out there for this sort of thing right now are the high-binned Cree XR-E and Luxeon Rebels. Both of these will be around 90 lumens per watt. This is in comparison to previous generations of high power LEDs, which were typically around 40 - 50 lumens per watt. What this means is that if you stick with these choices, you'll get roughly twice the light for the same power consumption and heat generated!

Besides the LEDs, you need a constant current power source. High power LEDs are extremely sensitive to drive current, both from a safety perspective (i.e. keeping them from popping) and from an efficiency and intensity perspective. Also, unlike conventional LEDs, they're pulling roughly 3 watts each, which means conventional methods for current control (i.e. a current limiting resistor) won't be feasible. So, you need to stick with a proven constant current design.

There are two popular drivers for these builds: 3021 series buckpucks, and Meanwell ELN-60 series. Both are available dimmable or fixed-current. The buckpucks cost around $15 each, can drive 6 LEDs, and require an external DC power supply. The Meanwells cost around $35 each, but can do 12 LEDs, and don't need an external DC power supply (you plug them right into the wall outlet.) Buckpucks are available with different max currents (350mA, 700mA, or 1000mA), while the Meanwells come with an internal trimpot to set the max current (700 - 1300mA, I think).

Spacing between the LEDs really kind of works itself out, IMHO. Figure out how many LEDs you need over your tank, then figure out the heatsink size(s) you'll be using, to get the most coverage over the tank's surface area. Then, just space the LEDs evenly on the heatsinks. For most people, this works out to 2 - 3" between the LEDs. Distance above the water is really up to you. For ease of tank maintenance, I'd probably want them at least 6" or 8" up. But, if you use optics, the light will be so directional it won't matter quite as much as with conventional lighting rigs - you could put them in the ceiling if you used optics tight enough.

A sheet of aluminum would be OK as a heatsink if you kept LED count low, ran at a reasonable current, and had a lot of air movement. Most people are using gigantic extruded heatsinks that are probably overkill, but given the total cost of these rigs a few extra dollars on the heatsink probably won't break the budget, and having more cooling than you need is never a bad thing. LED efficiency and lifespan are both dependent on operating temp, so it's something to keep in mind.

Choosing the number of LEDs, drive current, and optics (optionally) are all pretty dependent on the goals for the tank, i.e. if you'll be keeping high light corals or just staying with a fish only setup. To the extent of my knowledge, your tank will be the largest LED-lit reef yet, so good luck! :D

[saf1]

So after doing a bit of measuring and what not on the marineland 6 gallon I'm going to retro LED's into, I do think 6 LED's is the right number. I will probably buy at least two optics as well to try and shove more light around the back of the tank where the heater "may" be located as well as the pump pulls the water from.

The tanks dimensions are 16"L x 9"W x 14-1/2 so not a large foot print. I already have it and it was a great deal. My daughter also has one she keeps some fresh water fish in. If this works then we'll do her tank also and convert it :) Lord knows we have plenty of rock and sand to move - so this should be fun.

Going to go ahead with the standard meanwell that rapid led sells and 3 of the CREE XR-E Q4 Cool White 3W LED on Star and then 3 of the royal blues. I think that will probably be more than enough and fit within the constraints of the hood.

I will remove the standard bio wheel that it uses and leave it open as a pass though. If I want to run any media or such I can always stuff it there.

Other than that - was trying to post a image of the 100 gallon that I'll be removing the rock and sand from but looks like I'm doing something wrong. Oh well. Anyway - will place the order on Monday. Can't wait.

EDIT PART (I noticed after that the images took. Sorry):
First image is hood of the eclipse. This one is my daughters. The one boxed up looks the same though. She uses a LED she picked up for her planted fresh water. She wanted to try the sunbright LED that a local fish shop sells and we don't like them at all.

Anyway - second image is the left side of my 100 gallon. These two pictures really are all that is left of it after the crash a couple years back. Its just been on auto pilot to keep the sand and rockwork alive. No coral - just the crazy amount of orange / brown Zoanthids that has been taking over my tank...

Third image is right side of tank with lower light. I think this is the rock I'm going to put actually in this nano.

Before crash it housed a huge frogspawn that I had to frag monthly and give away and a super size elegance that I had forever. It started with one cup and mouth and grew to 5 cups each with their own mouth after I shut down the skimmer.

Anyway - if this goes as planned (which I'm working on now) then I will maybe get the itch to rebuild here after the start of the year.

[PJchicago]

Looks like it is time for a better multimeter. I did open up the meanwell, but no fiddling (yet) untill I get a handle on the multimeter.

So I've picked up a new multimeter, opened up the meawell and started to fiddle. I can now measure current but am still confused. It's the dimming functionthat is throwing me off.

I have 12 of the meanwell eln-60-48P drivers. In the final configuration they get ziptied in place and are not easy to get at, so I am hoping to get my max current set for good. I have not yet worked out what I will do for a permanent PWM dimmer, find a compatible controller or tackle arduino. To start I am just looking to bypass the dimming function at 100%. Based on my reading thus far, I thought any small amt of power running into the dimming circuit would power it up to 100%. I had 2 AA batteries wired together that I was testing the individual LEDs with so I used that. On the multimeter, no batteries connected = 0V and connected it jumps right to 48V.

Current, however, seems to be affected by the voltage applied to the dimmer wires. 3V in from my 2 AA batteries would register a max current of .35A, and using a 9V battery would register up to 1.47A. I have looked over the datasheet but the analog vs pwm dimming is throwing me.

datasheet here: http://www.meanwell.com/search/ELN-60/ELN-60-spec.pdf

D version of dimmer says 1-10V dimming. I definately have the P version but it still seems to react to incoming voltage.

Looking for guidance on how to accurately set the internal pot to max current so that once my real PWM dimmer is running it will drive them at less than 1A and not do any damage.

[PJchicago]

In that data sheet, it says PWM signal is also 10V and the graph looks roughly linear. With a 9V battery as a bypass, does setting a max current of 850MA sound about right to later keep me under 1A with a 100% 10V PWM dimmer signal?

Or am I completely lost???

[PJchicago]

Another thought, datasheet says pot can adjust current from 3% to 25%. I think that means 25% over the 1.3A. 1.3A x 1.25= 1.625A take that times .9 (for my 9V battery compared to the max 10V signal) yields 1.4625 which is very close to the 1.47A I was reading w/ 9V battery and pot all the way up.

Does this mean PWM can act as both 0-10V dimmer AND PWM dimmer?

I am gaining confidence in my 9v battery / 850 MA max setting. Any input? trying not to kill $1000 worth of LEDs.

Anyone know if the meanwell has some internal way to limit the dimmer voltage to 10V? Can I hook up a 12V wall wart and it will run as if 10V incoming? I could test but don't want to inadvertantly kill a meanwell too.

Thanks for any help.

[der_wille_zur_macht]

Personally, I wouldn't trust it outside of the operation outlined on the datasheet. If it says the PWM needs to be 10V, then I'd find a way to apply 10v - this can be as simple as a 12v wall wart. Most PWM circuits are tolerant of voltage over the rated amount, but if you wanted to be extra totally absolutely sure, you could put a voltage regulator on the wall wart, or use a resistor divider to knock it down to exactly 10v. Get that source, then adjust the max current.

The way I interpret the adjustment for current on the datasheet is:

-25% ~ 3%

i.e. minus 25% up to plus 3 % of 1.3A. At 25% under the factory setting of 1.3A, it would be 975mA. So, it's probably more or less safe to turn them all the way down on the internal trim pots, though I'd certainly check this with your multimeter.

I should add a disclaimer that I don't own this exact driver so this is more or less all speculation based on my interpretation of the datasheet. :)

[ScooterGirl]

I've got a DIY lighting controller based on the open-source arduino that'll fade several banks of LEDs up and down to simulate sunrise, travel across the sky, and sunset. It'll also simulate moon cycles at night, and do a "storm mode" where it dims the lights for a variable amount of time (an hour or so) every few days to simulate clouds passing across the sky.


I am really hoping you can help me with a planning problem I am having for an LED system (I'm starting with a LED moonlight that follows the phases of the moon). Coding the Arduino isn't an issue; I write code for a living. As for electronics, however, saying I know next to nothing would be an overstatement.

I have googled high and low trying to find information on how to actually wire a dimmable buckpuck to an Arduino Duemilanove board. I'm pretty sure the VIN + and - goes to the external power supply I am using to run the buckpucks and LEDs, the LED + and - are connected to the LED string and CTL goes to one of the digital pins (say pin 9) on the Arduino. I can't figure out what to do with the REF wire. Does that go anywhere?

Also, I am going to be using a DS1307 clock from Sparkfun electronics that's already soldered to a breakout board. The wiring for that is (I think) SDA to Arduino analog pin 4, SCL to Arduino analog pin 5, GND to Arduino Power GND and 5V to Arduino Power 5V. What I'm unclear on is connecting the wires to the breakout board. Do I just solder the wire into the holes?

Any help you could give would be greatly appreciated!

[der_wille_zur_macht]

I am really hoping you can help me with a planning problem I am having for an LED system (I'm starting with a LED moonlight that follows the phases of the moon). Coding the Arduino isn't an issue; I write code for a living. As for electronics, however, saying I know next to nothing would be an overstatement.

I'll trade you hardware advice for coding advice! :D My programming skills are outdated and weak, so I probably code like a slob. I'm sure I'm going to need help at one point or another.

I have googled high and low trying to find information on how to actually wire a dimmable buckpuck to an Arduino Duemilanove board. I'm pretty sure the VIN + and - goes to the external power supply I am using to run the buckpucks and LEDs, the LED + and - are connected to the LED string and CTL goes to one of the digital pins (say pin 9) on the Arduino. I can't figure out what to do with the REF wire. Does that go anywhere?

You're right, the + and - Vin connections from the buckpuck go to the external supply. The CTL goes to the pin you'll be using for control. You want a pin capable of PWM unless you're going to do some wicked coding magic to make a regular GPIO pin provide an analog signal. You also need to mate up all your grounds. So the ground from the 'duino needs to go to the power supply ground. In theory, you could power the arduino from the REF wire on the buckpuck, since it provides a low-current 5v DC source meant for use in a dimming circuit. Though, if you are doing other things with your arduino you'll probably exceed the current rating on that connection (I think it's in the datasheet).

There's also a diagram in the buckpuck datasheet that shows an external signal controlling a transistor between REF and CTL with a few resistors. Someone else on this forum is using that circuit with success.

Though neither of those options strike me as ideal, since you're basically turning the buckpuck on and off rapidly to simulate dimming, instead of actually changing the setpoint for LED drive current as you'd get with an analog voltage signal on the CTL pin. You could rig a resistor-capacitor filter on the arduino's PWM pin to translate the PWM signal into an analog signal, though you'd have to do some research to get the values right.

Also, I am going to be using a DS1307 clock from Sparkfun electronics that's already soldered to a breakout board. The wiring for that is (I think) SDA to Arduino analog pin 4, SCL to Arduino analog pin 5, GND to Arduino Power GND and 5V to Arduino Power 5V. What I'm unclear on is connecting the wires to the breakout board. Do I just solder the wire into the holes?


I'm using a home-made copy of that board based on the same chip. Your description is more or less right. I'm not a duemilanove user so make sure you're connecting the 5V pin to a real, regulated 5v source on the duemilanove, not an unregulated Vin source (many Arduino boards have both so be sure you get the right one.) Also, technically, there should be pullup resistors on the SCL and SDA I2C lines. The Arduino has internal pullups, but they're extremely weak and prone to noise in the real world. So throwing a resistor in the 3k - 5k ohm range on to each line wouldn't hurt (check that the SparkFun board doesn't already have these - I'm 99% sure it doesn't but not totally positive. Most slave devices don't come with them, since you only need one per I2C bus).

How you actually make the connections is up to you. Personally, since it's a separate PCB, I would not just solder wires between the two. Instead, I'd solder a header (plain old male or female .1" like the duemilanove comes with) on the SparkFun RTC board, then make a little cable to connect the right pins on the duemilanove to the RTC. IMHO this is a little more robust, and it keeps the two boards reusable without desoldering.

[Canoe]

..... how to actually wire a dimmable buckpuck to an Arduino Duemilanove board. I'm pretty sure the VIN + and - goes to the external power supply I am using to run the buckpucks and LEDs....

someone who knows the specifics posted while I was responding, so I just deleted my cautionary best guess on CTL and REF that appeared there

[saf1]

Quick question. I was placing the order for the drivers tonight and led's when I noticed that the meanwell driver uses a different model number. This is what they are selling - is this the correct one that most are using?

Mean Well LPC-35-700W constant current driver for 23 bucks.

I'm just driving 6 LED's. However, I also see the 60 series that is dimmable. Since I wasn't going to dim I figured the 35 series was the correct one to use but figured I better ask. 23 bucks for the 35 series, 44 for the 60 series. Big difference - so wanted to ask.

Rapid led btw (if it matters)
Mean Well ELN-60-48P dimmable driver
Dimmable driver for driving CREE 3W LEDs


Mean Well LPC-35-700W constant current driver
For driving 1 string of 3x3W ~ 12x3W CREE XR-E LEDs in series

[rhoptowit]

so were are the PAR numbers?

[yupgopotty]

Quick question. I was placing the order for the drivers tonight and led's when I noticed that the meanwell driver uses a different model number. This is what they are selling - is this the correct one that most are using?

Mean Well LPC-35-700W constant current driver for 23 bucks.

I'm just driving 6 LED's. However, I also see the 60 series that is dimmable. Since I wasn't going to dim I figured the 35 series was the correct one to use but figured I better ask. 23 bucks for the 35 series, 44 for the 60 series. Big difference - so wanted to ask.

Rapid led btw (if it matters)
Mean Well ELN-60-48P dimmable driver
Dimmable driver for driving CREE 3W LEDs


Mean Well LPC-35-700W constant current driver
For driving 1 string of 3x3W ~ 12x3W CREE XR-E LEDs in series

If you aren't going to dim, just get the LPC-35-700W. Much cheaper and easier to use. That is the one I'm using.

[der_wille_zur_macht]

If you aren't going to dim, just get the LPC-35-700W. Much cheaper and easier to use. That is the one I'm using.

Agreed. Though technically the 60-48 has a ton more capacity in addition to dimming, though in this case that's not needed either.

[tor101898]

subscribed ,great idea

[saf1]

Thanks all. I went ahead and placed the order - hopefully everything arrives sometime this week. This should be fun. If sucessful then I'm sure to get fired up and plan my 100 gallon replacement with something that can hold the existing 100 gallon for a sump - so maybe 120 or so.

I would like another lagoon style tank with sand, some rock, lots of open area, and a elegance. Maybe some birstnest up top on the rocks would be cool. Who knows - but this is cool.

Thaks for the clarification on driver. Soon :)

[der_wille_zur_macht]

The best part about doing these builds on a nano is that you can try a million things in the same afternoon with very little cost. I learned a TON by playing with the angle, height, spacing, heatsinking, drive currents, optics, etc. on the various nano fixtures I built - it was a much more explorative and educational experience than I'd hoped, and will definitely help with my next big tank.

[HerdofCrickets]

Any thoughts on this fixture?

http://cgi.ebay.com/LED-Aquarium-Lighting-Reef-Corals-Tank-Grow-Light-Panel_W0QQitemZ390114734604QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5ad4a6720c

[der_wille_zur_macht]

I'm going to be blunt and honest. IMHO it's worthless.

There are no reliable specs on the LEDs used, so we can't verify output or efficiency claims. Plus, if you do some simple math on their numbers, it doesn't work out to match any of the high efficiency LEDs out there, so either the numbers are made up, or they're false.

Even if you give them the benefit of the doubt and assume they've found an LED we don't know about, think of this: even if they were buying their raw parts in bulk (i.e. 1000+ LEDs at a time, straight from the manufacturer) they'd be losing money on each unit, unless the LEDs they were using were significantly cheaper than the LEDs we all know about. And, if there was an LED out there with those specs for that price, we'd know about it. :D

Why make such a big deal about efficiency? IMHO it's one of the most important things for an LED build, since it's one of the most obvious things that separates LEDs from MH or T5. If you go with less efficient LEDs, you might as well just go with MH or T5 - low-efficiency LEDs will use just as much (or more) power, produce just as much heat, etc.

Also, keep in mind that the difference between top-bin XR-E and bottom-bin XR-E is like 50% in terms of output per watt consumed. And we consider it to be one of the best. The difference when you compare to other models can be hundreds of percent. Since we have no idea what LED is used in that fixture, it's anyone's guess.

[HerdofCrickets]

Logic wins again... and my dream of a cheap light fails again!

[der_wille_zur_macht]

:lol:

Sorry. I typed that after a frustrating conference call, it came across a little harsher than I intended.

[james3370]

i bought a similar one from the same seller to use over my cheato in the refugium, but don't think i'd use one on an actual dispaly tank. the one i bought also was ALOT cheaper lol

some pics (clickable thumbs) of the light & 3 of it actually on (no flash 2nd & 3rd...soft flash on the 4th pic)

http://img.photobucket.com/albums/v501/james3370/tank/29%20build/th_CIMG1844.jpg (http://img.photobucket.com/albums/v501/james3370/tank/29%20build/CIMG1844.jpg) http://img.photobucket.com/albums/v501/james3370/tank/29%20build/th_CIMG1845.jpg (http://img.photobucket.com/albums/v501/james3370/tank/29%20build/CIMG1845.jpg)

http://img.photobucket.com/albums/v501/james3370/tank/29%20build/th_CIMG1849.jpg (http://img.photobucket.com/albums/v501/james3370/tank/29%20build/CIMG1849.jpg) http://img.photobucket.com/albums/v501/james3370/tank/29%20build/th_CIMG1847.jpg (http://img.photobucket.com/albums/v501/james3370/tank/29%20build/CIMG1847.jpg)

[my2girls]

I ordered my 24 premium kit today along with the heat sink for my BC29. I know yupgopotty epoxied his LEDs to the heat sink. From what I have been reading, drilling and tapping is recommended instead. This seems like a lot more work. Is it worth it?

[yupgopotty]

I ordered my 24 premium kit today along with the heat sink for my BC29. I know yupgopotty epoxied his LEDs to the heat sink. From what I have been reading, drilling and tapping is recommended instead. This seems like a lot more work. Is it worth it?

I think it'll definitely give you more flexibility in case you need to replace a bulb or change the set-up. The epoxy is pretty permanent, though I have pried a few off after realizing my positioning wasn't quite correct. Having said that, these LEDs are supposed to last 10+ years and if your cooling is sufficient, I don't really think drilling and tapping all those holes is really necessary. I've done it both ways and the drilling/tapping was pretty arduous, with not a whole lot of benefit for my small fixture.

[saraiva]

The original Cree lens is accidentaly droping out, what should I do ? There is a especific adhesive ?

[Daemonfly]

The epoxy is a decent solution for those not wanting to drill/tap.

But, for those willing to drill their holes, I would still suggest not tapping them. At the size needed, I'd bet 90% of the people here would break off at least one tap in a hole, due to the small size of tap required. Imho, drill your holes and use a self-tapping machine screw. These require a bit more torque when driving the screw in, but a lot less work overall. Chamfer the hole to prevent an edge forming up during the initial screw-in.

[der_wille_zur_macht]

I'm drilling all my builds now, but mostly because I have a drill press so it's easy and precise. In theory, screws and good thermal paste give a hair better thermal performance than epoxy or tape, but most people seem to be over-cooling their fixtures (a GOOD thing!) so it's definitely not critical.

[yupgopotty]

The original Cree lens is accidentaly droping out, what should I do ? There is a especific adhesive ?

Do you mean a lens/optic that goes over your LED, or the glass part of the LED itself?

[saf1]

Wow - my LED's arrived today as did the meanwell driver. I placed the order yesterday and didn't expect them for 3 days or so. Neat little box arrived with everything in it. Too cool.

Hopefully its allowed, but rapid led was beyond fast. Maybe due to a small amount of LED's but from time to check out, paying, then confirmation , then confirmation of shipment - I couldn't ask for more.

[saf1]

Ok - so now that I have the goods, a couple questions :) I'm going to have to re-read a lot of this stuff too just to make sure.

I'm looking through my junk bin to see what sort of heat sinks I pillage now. I have some smaller computer chip pieces that actually look promising. This is a smaller configuration so I don't want to use a huge block of aluminium if a piece will work.

I was also looking at a piece of thin aluminum that was a MH reflector. I could fold this a bit and make it into something I could attach them to - it would allow a form fit if you will that I could also angle a bit if so needed. Hmm...I'll need to think on that one.

Is there a recommended wire gague to use? It looks like 16 gague used on the driver. If not I wanted to use whatever it was to remain consistent.

Soldering tips? Low heat, heat sink - anything to alert a first timer?

I will probably use tap and die or sheet metal screws - we'll see what they will be mounted on. Hard to tell at the moment.

[saraiva]

Do you mean a lens/optic that goes over your LED, or the glass part of the LED itself?

The glass part of the LED itself.

[der_wille_zur_macht]

Ok - so now that I have the goods, a couple questions :) I'm going to have to re-read a lot of this stuff too just to make sure.

I'm looking through my junk bin to see what sort of heat sinks I pillage now. I have some smaller computer chip pieces that actually look promising. This is a smaller configuration so I don't want to use a huge block of aluminium if a piece will work.

I was also looking at a piece of thin aluminum that was a MH reflector. I could fold this a bit and make it into something I could attach them to - it would allow a form fit if you will that I could also angle a bit if so needed. Hmm...I'll need to think on that one.

I'm not enough of an expert to whip out formulas and prove it, but I'm getting the feeling lately that many people over-cool their LEDs. Not that this is a bad thing, though. But, for instance, I'm running a few nano rigs with 8 LEDs at 500mA on a smallish (say, 3"-4" square) heatsink meant for a PC CPU. With a fan, it's reasonable.

How thick is the reflector material? All the reflectors I've ever used have been pretty flimsy. I'm not sure I'd want to go below 1/8" if I was going to just use sheet stock instead of a finned heatsink, you'd getting pretty low on mass below that.

Is there a recommended wire gague to use? It looks like 16 gague used on the driver. If not I wanted to use whatever it was to remain consistent.

The consensus seems to be 16 gauge zip cord from wall to driver and driver to LED array. The cheapest way to get this is to hack the cheap extension cords you can get for 99 cents at hardware stores. Between LEDs on the array, solid core 18 - 20 gauge.

Soldering tips? Low heat, heat sink - anything to alert a first timer?

99% of people are mounting the LEDs physically to the heatsink, then soldering. This presents some difficulty, since the heatsink is going to kill your soldering iron. So, use the most powerful iron you can get your hands on, tin everything, and be patient.


The glass part of the LED itself.

How hot are you running those things? :D I've had LEDs where the built-in lens got a little "sloppy" and loose, but never had one fall off.

[wesley6610]

I believe that the soldering aspect was the most time consuming part for me and the most difficult as well. However, I used stranded wire as opposed the solid core copper 18 gauge...I believe that it will work the same no matter what, but if I try an array in the future perhaps the solid core will cut my connection troubleshooting time in half.

[saf1]

Well - the flashing I was going to use is pretty thin. However, I found a old ballast I am no longer using that actually is housed in 1/8th aluminum. So I'm going to actually cut this to shap I think and then screw it to two mounting holes already in the hood. This way it will have air above it and below it. Pretty large surface area since I'm only using 6 leds.

Odd question - I'm looking for a wire diagram or image of a build. The meanwell lpc 35-700 has a blue and brown wire which clearly says AC in. So this is my power source to AC / wall. Then on the other side is a black and red wire which say DC out. This must then go to the leds.

The leds don't really show anything so that is what I'm trying to picture. I'm assuming red wire goes to the first led, then single wire to the next and continue the daisy chain until the last led. Last led also has a wire that gets routed to the black to complete the source?

Am I on the right track?

[saf1]

Nm....go back to page one and you will see a example :)

[Boomstick]

FYI all, just saw this on RapidLED

***We are having a blow-out sale on all CREE XR-E Q4 Cool White LEDs! For a limited time we have reduced our price to $5 each, with LEDs + Lenses only $6!! Buy now before prices go up on November 15th!!***

[james3370]

FYI all, just saw this on RapidLED

***We are having a blow-out sale on all CREE XR-E Q4 Cool White LEDs! For a limited time we have reduced our price to $5 each, with LEDs + Lenses only $6!! Buy now before prices go up on November 15th!!***

http://img.photobucket.com/albums/v501/james3370/random%20funny%20pics/Quagmire.png

too bad i'm (1) broke & (2) not doing any builds in the near future

[barderer]

instead of ordering the LED's on their little star board, could I just order up a PCB sized for my project and direct mount the bare leds? This way I could avoid the hassle of soldering on the heat sink then mount the whole PCB on the heat sink and hook the power direct to it? Am I totally off here or is that a good idea?

:)

[kcress]

instead of ordering the LED's on their little star board, could I just order up a PCB sized for my project and direct mount the bare leds? This way I could avoid the hassle of soldering on the heat sink then mount the whole PCB on the heat sink and hook the power direct to it? Am I totally off here or is that a good idea?

:)


Not a good idea. Reason is that the star boards are not 'typical' PC boards. They are rather exotic metal clad boards. They will carry the heat away from the LEDs far better than regular board. And no, do not even vaguely consider having the whole board made from metal clad as it will cost a fortune. Last I checked board houses wanted to charge horrendous adders for using metal clad. (like more than a thousand dollars):eek1: