Ok so, I've been pondering on ideas for how to light the 20 gallon long I am (hopefully) starting soon. I was originally thinking of getting some sort T5HO/MH combination, but after tirelessly reading through various LED threads, decided it would be much more fulfilling to do one myself. This obviously means much more time between now and when the tank goes up but... oh well

So as far as I understand, I will need the LED's, an appropriate heat-sink, drivers, a power source, cooling fans, and appropriate wiring. It seems that, being only 12" tall, optics would not be necessary for this tank.

Now then, some questions. First of all, how many LED's would be necessary for this project? I think evil told me a 10 x 2 array would be appropriate in another thread... If so I was thinking 10 Q5 Cool-White XR-E's, and 10 Royal Blue XR-E's. How many drivers would be needed to run this array and at what current would I need to run this at?

Lastly (for now) and probably most importantly... how hard is it / what is the failure rate for the average DIYer to build a successful LED unit???

if you are doing 10 of each color i woud use meanwell dimmable drivers so you can adjust each color to your preference. meanwells do not require powersources so that saves you a little trouble but they cost more than buckpucks so its a trade off.

now for how many failures, i have yet to see any thread where somebody tried to DIY an LED array and failed so that should give you some encouragement. now if you know how to solder you will be set. if you do not want to drill the heatsink and use screws to hold the LED stars down there are alternatives which makes the process easier(and faster lol). these alternatives are thermal pads or a thermal adhesive. other than that it is just wiring everything together.

good luck

I'd probably go with 24 LEDs on a 8 x 3 array. That way you get the most out of the drivers (either buckpucks or meanwells)

If you go with buckpucks you are able to hook 6 LED per driver
If you go Meanwell you can hook 12 LEDs per driver

Buckpucks need external power supply (24V 5A at least)
Meanwells connect directly to 120v AC

You can run this at a current between 700mA~1000mA

If you have some basic knowledge about soldering and have the proper tools it'll be easy to so it. Just make sure you wired everything correctly and check and recheck you did it right. Did I mention to triple check?

I am in the same boat of lighting a 20L. I have decide on this led coverage It is 10 in the back and 9 in the front 3 in apart front and back. 2.25 in apart side to side. I think the thermal pads are the best and most simple option ( the drilling and tapping seem to give most the biggest headaches) These opinions are just based on research and my decisions take it for that.

thanks for the input mustang and sammy, based on your info i did some more research and found this. it seems to be exactly what i would want in my situation, and even comes with optics if i decided i wanted to use them.

and sammy, i have done some soldering work before on guitars and such and have a pretty good idea of how to do it, but will definitely practice first. thanks for the triple check hint

i want to look into some of the retrofitting that has been done with these and figure out what i could make as far as that goes, and try to start planning out how i want this to be done this week!

That kit has all you need. Keep in mind this kit comes with Meanwells "P" model which requires to DIY a controller to have dimming option. Otherwise you can just connect it to a 10V wall wart to have 100% output. You don't really need optics though. Depending on how high you place the lamp. Repidled doesn't carry Meanwells "D" models which reuires also a DIY controller but easier to do.

Checked with nanotuners.com and for 24 LEDs and 2 Meanwells "D" model you have a total of: $230.86

That gives you room to get the thermal tape or even the thermal epoxy and some cable.

Anyways, Mike from rapidled is a great guy, very responsible and ships very fast. Is always available to answer any questions or help.

Just a FYI

ah ha a great site that i hadn't yet run into! thanks for the share.

ok so, with 24 LED's, and the meanwell "D-Series" drivers, what else is required to run the lights? With so much information to search through its easier to just ask sometimes... so sorry for the beginner questions... but the Meanwell drivers don't need a separate power source correct? Also, what else would i need for the dimmable option?

correct meanwells have a powersource built in.

OK, this is where it gets a little tricky. I am new to this also, but I will try to describe it the best I can and as I under stand it. The driver has a pair of wires comming off it for a dimmer. The driver looks to those wires for a 1.5v-10.0v signal to indicate the desired brightness. Unfortunately, there is really nothing out there you can buy to do this, so have to build your own.

You will need to buy these parts...all available at radioshack:

1 x 12v 1000ma wall adapter
2 x LM317
2 x Linear Taper 10k Pot
2 x 1k ohm Resistor
2 x 470 ohm resistor


And then will wire it like so:

I saved this picture, and I cant remember who orignally posted it. Whoever took it; Thanks, it has been helpful, and I hope you dont mine me posting it.

+1 what DustnF said.

You can also run the 10V wall wart directly to the dimmer wires to get 100% light.
Search in the lighting forum for the meanwell driver thread. There are pics, diagrams and info about this

yeah the dimmable option i might have to hold off on and possibly do later, but at this point i think all i'm going to try and go for is the simpler option and just have 100% all the time. i will do some searching and check out what other people have already done and diagrammed with the meanwells though to get a better idea. very helpful info everybody, its much appreciated. hopefully i can get something drawn up soon and see what you guys think. i want to try and figure out how far apart the rows and lights should be and start from there, but i'm starting to believe i may actually be able to do this

ok so. been doing some more researching and trying to draw something up. i was thinking either and 8 x 3 or two separate arrays that are something like this (x's being the led's)

x x x x
x x x
x x x x (the middle row would be offset but the spaces i put in don't show up in the post)

with one inch between the rows and each individual LED. would an 8 x 3 array be more beneficial for even coverage since it would limit gaps between the two arrays? my thinking was that it might be easier to wire this way... not sure if thats true though now that i think about it. I think an 8x3 array would require a heatsink about 10" in length by 5.5" if the LED's and rows were 1.5" inches apart correct?

also, on another note. the Meanwell ELN 60-48D drivers. Do these require something else, a 10v adapter i believe i heard about? to work?

thanks for any input.

Looks like a good design. I'll be following your progress. I hope to use your thread as a guide when I start my 20L LED build. Good luck and continue to keep us posted on your progress.

lights and drivers ordered and on their way. bought from Rapid LED

could anybody tell me if this would work for securing my LED stars to the heatsink? i didn't want to drill and tap and also am not sure where to find the thermal pads. this stuff is rated at 25% metal oxide compound, thermal conductivity >1.29 W/m-k and a thermal resistance of >0.12.

as always any input is greatly appreciated. i have almost everything i need besides a trip or two to radio shack so i'm trying to get this done this week while i have spring break. thanks again.

I'm afraid that thermal paste won't work for securing the LEDs to the heatsink without drilling and tapping. looks very similar to the arctic silver compound. You need some kind of thermal epoxy. Check the one from rapidled. I've used it without any problems in a few projects. It's a two part mixing one

thermal compound is just a filler that fills the gap for better heat exchange.

u should have gotten the MX-3 heatsink compound. its 8.9 W/m-k

nonotuners.com has the pads. I used them and they work great.

Bob



Correct spelling - nanotuners.com has the pads. I used them and they work great.

Bob

yeah i know they are readily available online, but like i said this week is the week i want to do it so having to wait for an order to come in is going to push the whole thing back indefinitely. i'll look around some stores and try to find other/better stuff that can be used, like mx-3 stuff mentioned earlier.

thanks guys

ok, so. I ordered the thermal pads from nanotuners since i had no luck finding anything in any of the local stores. they got her two days ago so i went ahead and started building my fixture. i got everything soldered and tested with a 9v battery and both strings of 12 are in working order. however, after getting one of the meanwells connected to the white array and plugged in, the lights just barely flicker... one time when unplugging them the entire string lit up for just a second. i'm sure i've read about this happening to somebody before but can't remember where i found it. can anybody give me an idea of what is going wrong???

by the way, once this is finished and in working order i plan on making a build thread to show all my progress

oh oh almost forgot! with the meanwells i took the top casing off and attempted to turn the svr2 knob? all the way down but it just kept spinning. i've heard of this happening before but what does it mean and will i need to send them back to rapidled to get a replacement??

If the pot is spinning, you will have to get a replacement unless the driver just so happens to be set at the right current. You are applying a voltage to the input of the driver right? You need something to get the drivers to light.

yeah to the input of the driver is a replacement power cord that plugs into the wall

does this driver have the dimmer wires and do you have a 10v supply going to it ?

The dimmer wires are exposed. No 10v supply

does the ELN D series drivers need to have a 10v supply in order to work?

Yes they do.

do the ####

Edit: then build mine!

Tagging along. keep us posted when you get this going.

tracking & bump

i bought all the parts needed to dim yesterday, now i just need to understand how to wire it. i'm building the circuit somebody posted earlier in this thread when i get the time this week. i will update my progress as i make it and then hopefully be able to make an easy to follow step by step thread of everything i did and maybe help somebody else out because of all the help i've gotten so far with this. thanks for the interest!

ok i'm sitting here trying to figure out how to build this thing but i am still very confused as i have no circuitry experience. can anybody tell me exactly what goes to what or what goes where - in laymans terms? pleaseee?

The pcb has two sides. One with copper on it, one that doesn't. Insert from the non copper side, solder of the copper side. Follow the picture for placement and solder everything down.

can anybody tell me why this circuit is not working??


is something wired incorrectly or something? when i plug the the ac in side into the wall as well as the 12V source from the dimmer circuit... nothing. except when i go to unplug both and i get the same thing that was happening before and that is the delayed startup from dim to bright of the whole array of lights before cutting out...

what kind of voltage are you getting from your dimming circuit?

i have to wait till next week to get the voltometer back, i figured if i turned the 10k pot all the way down it couldn't do much harm. but when nothing happened i tryed turning the pot up some but still nothing.

anybody?