JP's DIY LED Fixture

[jpccusa]

My background: I have no experience with electronics and I am somewhat afraid of electricity. I am a business adm student and full time worker. I'm a DIYer by nature. I decided to do this project so I can have something top of the line, changeable/fixable, and cheaper (http://reefcentral.com/forums/showthread.php?t=1971330).

Tank Background: 60W x 24D x 18L Acrylic, live rock and sand, reef-safe fish, mushrooms and Xenias.
My previous lighting was 3 Helios T5 (plug/play type) (http://www.commodityaxis.com/ProductData.aspx?id=67) but I am not longer able to find those for sale.
The wood canopy has a frontal angled lid, which reduces the mounting area for the LEDs to 12 inches.

After a few months of reading and many private messages, this is...

The Plan: 48 Cree LED (60W * 12L / 15 square inches per LED) driven by 2 Meanwells ELN-60-48D, wired in parallel (2 strings of 12 LEDs each driver). Two potentiometers (1 per driver) will control dimming separately for blues and whites for color temperature adjustment (References 1 (http://reefcentral.com/forums/showpost.php?p=18283110&postcount=270) & 2 (http://reefcentral.com/forums/showpost.php?p=18286342&postcount=272)).

Color: 24 XP-E Royal Blue + 16 XP-G Cool White + 8 XP-G Neutral White + 2 XP-G Warm White

Heatsink: Home Depot has 3/4 U-channels (http://www.homedepot.com/h_d1/N-5yc1v/R-100338033/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053) for less than $11/8ft.. I'm aware the LED star is slightly wider, but I don't see a problem with that.

Cooling: Two 120mm fans

Other Parts: - 4 x 1A Quick Blowing Fuses (one per string)
- 4 x 1.0 Ohm, 1% accuracy, 3 or 5W Resistors (one per string)
- 8 x terminal blocks (four per driver)
- 20 gauge pre-tinned wires
- 1 x 10V power supply
- Thermal compound (I have Arctic Cooling MX2 but unsure if that will work)

Please share your opinions (http://www.answers.com/topic/opinion). Will this work? Can anything be replaced or improved while keeping the present cost? Is there any mandatory changes that should be done? Etc.

I will try to take pictures of the construction process once it starts. :celeb1:

[katchupoy]

Is that 60L x 18W x 24H tank?

You can also use 1inch square bar $15.00. The idea is more surface area.

How many linear strips will be used?
How many LEDs per strips?

If this the only lights that will be used. Fans are optional. (depends on spacing)

Thermal compound? You will need Thermal Adhesive not Compound? Its a Part A & B that you mix together.

Terminal blocks? I really like this one... compared to the other one...
http://javedplastic.com/images/products/panel-box-items/terminal-blocks.jpg

[TheFishMan65]

Have you seen actual tanks with your color mix? Everyone is different but I like my cool white and royal blue mix. If you do all CW it will be cheaper unless you decide you don't like and then will have to replace them. You may also want to consider changing some of yourCW to RB since the XP-G are brighter than the XP-E. I can't give you advice on the right mix or color, but I can ask question to make you think and hopefully end up happy :)

Other than that after first read it seems good.

[katchupoy]

So you are doing series/parallel. Are you doing it the safe way? or the risky/fuse way?

[TheFishMan65]

katchupoy,

Why not compound and screws?
I also thought square tubing was a no no because the heat could not escape the inside (unless you blow from the ends).
Do you have a link to those blocks?

[EDIT]
What do you consider the safe way and why are fuses risky?

[kcress]

Yes, a square tube is far worst for cooling than U-Channel. Probably less than half as effective.

Suggestions:
Use these terminal blocks if you want 2-position:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=A98503-ND

or use these if you want 6 positions:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=A98507-ND

Use these resistors:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=UB5C-1.0-ND

Use these fuses:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=F2313-ND

[katchupoy]

Aha, I overlooked the screws... my bad.

Square? good point. My argument is that both ends are open, so its not really that they cant escape. Square will have 4 sides of surface area (1 inch per side). More mass? Against 3/4 inch of only 3 sides. Less mass? Just my experience and my opinion.

Blocks. Hmmm i bought it from local radio shack.
http://www.radioshack.com/product/index.jsp?productId=2103231

Safe way or risky (fuse) way. Based on my build thread where the OP linked, I explained to him the + & - of doing series/parallel. And a lot of experts mentioned that it can be done by means of safety fuse, but there is a risk. Now on the last part, I mentioned that if you really want it safe, even without the use of fuse, then you can do it in a certain way. Thats why I asked him, which direction is he going to go.

[katchupoy]

Yes, a square tube is far worst for cooling than U-Channel. Probably less than half as effective.

Maybe because of the surface area exposed to air? And since I have 4 sides (square) the U channel has 6 sides exposed to air? Good point....

What temp (without fan) should we see with these HP LEDs at normal (safe) operating temp?

[jpccusa]

Is that 60L x 18W x 24H tank?

Yes

How many linear strips will be used?
How many LEDs per strips?

4 strips of 12 LEDs each.

Have you seen actual tanks with your color mix? Everyone is different but I like my cool white and royal blue mix. If you do all CW it will be cheaper unless you decide you don't like and then will have to replace them. You may also want to consider changing some of yourCW to RB since the XP-G are brighter than the XP-E. I can't give you advice on the right mix or color, but I can ask question to make you think and hopefully end up happy :)

Other than that after first read it seems good.

I have been reading the emperor's got no clothes thread (http://reefcentral.com/forums/showthread.php?t=1885076)...
I also PMed a few members about color aesthetics (I like shallow water/less blue look).
I have not yet seen pictures of tanks with the mixture I am planning. That would actually be awesome!
I really appreciate your questions and input... Now you are making me rethink the number of RB's. :D


Suggestions:
Use these terminal blocks if you want 2-position:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=A98503-ND

or use these if you want 6 positions:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=A98507-ND

Use these resistors:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=UB5C-1.0-ND

Use these fuses:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=F2313-ND

You're a life saver :thumbsup:

So you are doing series/parallel. Are you doing it the safe way? or the risky/fuse way?

Safe way or risky (fuse) way. Based on my build thread where the OP linked, I explained to him the + & - of doing series/parallel. And a lot of experts mentioned that it can be done by means of safety fuse, but there is a risk. Now on the last part, I mentioned that if you really want it safe, even without the use of fuse, then you can do it in a certain way. Thats why I asked him, which direction is he going to go.

I am doing the fuse way, which based on what I understand is pretty safe.

Please correct me if I'm wrong, but in case something goes wrong (1 blown LED), the only thing it would happen is the fuse would blow up (<$1 loss), stopping the excess of electricity to burn all the rest of LED's, right?

Why do you call this method risky?

[katchupoy]

Using risky on my part is inappropriate use of word. My bad. Maybe also not fully understanding it well.

Kcress? If you have 2 string of 12 leds in series connected in parallel, what will happen to the string if one led goes bad? Will it die "closed"? meaning the rest of the series will still have power or "open"? meaning that the continuity will be broken thus no more light for that particular set of 12 leds.

[jpccusa]

Another question would be why doesn't everyone do the parallel setup in order to save space and money with the drivers? Is it only because it requires much more "tweaking" in order to have the strings balanced?

[kcress]

Tubing doesn't work as well for a few reasons. One is that more mass is not better because this is a steady state situation. If these were flash LEDs then mass would be everything. Energy could be dumped into a mass with low temperature rise. Then the heat could dissipate over time to the environment. But since our application is one that runs for more than a few minutes at a time, it switches to surface area being the important variable.

A bunch of the heat leaves heat sinks via radiation. Warm things radiate to their colder surroundings. This is direct line-of-sight stuff. The greater the difference the higher the radiation transfer. When you use a square tube the entire inside face can never "see" another surface with a lower temperature. This means radiant cooling is fully blocked by all that inside surface area. This makes the heatsink effectively much smaller. A U channel would've allowed all it's inside surfaces "see" somewhere cooler.

Blowing air through the center is lousy too, because it's pretty hard to actually get air to blow down those tubes. They don't well match any fans and if they do the air gets warm and the "other" end gets the hot air from the first end.

As for parallel. As katchupoy has pointed out, if you're multiple strings end up with a situation where if one is open and ceases carrying current the others are still below their maximums you could probably dispense with fuses. You would notice your lighting was strange and could take action.

If on the other hand if a string opening will immediately over-current the remaining strings it would be better to have the fuse. Most of our LEDs will take an amp for a while without undue stress if the cooling is adequate. That means a 1A fast blow fuse has enough time to open preventing a burn out or a lot of stress to the remaining LEDs.

In reality if you over amp a string, probably one LED will burn-out open and act as a fuse anyway, but I'd rather have a fuse do it. Occasionally LEDs fail shorted like incandescent bulbs that get superdupermegabright for a few seconds after they've actually failed. In that case you could have several LEDs in a string damaged which a fuse should mitigate.

Not paralleling is simpler.
It costs more. It's less efficient. It causes more harmonics. Uses more space. Is heavier. Entails more power cordage. Requires more dimming solution. But it's more straight forward and works. Hence some people choose it. Since our typcial ELN60-48 can reasonably support 2 strings it really makes more cents to add a few bucks of components and do some simple balancing, instead of adding another $30 driver.

[jpccusa]

Following up on this post (http://reefcentral.com/forums/showthread.php?p=18243243#post18243243), here are some pictures I took a few minutes ago

138458 138459 138460

I'm actually pretty happy that the inside of the channel is 3/4 inch, meaning the aluminum is 7/8 inch, or 0.875. I think the star will fit just fine! :rollface:

[katchupoy]

Tubing doesn't work as well for a few reasons. One is that more mass is not better because this is a steady state situation. If these were flash LEDs then mass would be everything. Energy could be dumped into a mass with low temperature rise. Then the heat could dissipate over time to the environment. But since our application is one that runs for more than a few minutes at a time, it switches to surface area being the important variable.

A bunch of the heat leaves heat sinks via radiation. Warm things radiate to their colder surroundings. This is direct line-of-sight stuff. The greater the difference the higher the radiation transfer. When you use a square tube the entire inside face can never "see" another surface with a lower temperature. This means radiant cooling is fully blocked by all that inside surface area. This makes the heatsink effectively much smaller. A U channel would've allowed all it's inside surfaces "see" somewhere cooler.

Blowing air through the center is lousy too, because it's pretty hard to actually get air to blow down those tubes. They don't well match any fans and if they do the air gets warm and the "other" end gets the hot air from the first end.

As for parallel. As katchupoy has pointed out, if you're multiple strings end up with a situation where if one is open and ceases carrying current the others are still below their maximums you could probably dispense with fuses. You would notice your lighting was strange and could take action.

If on the other hand if a string opening will immediately over-current the remaining strings it would be better to have the fuse. Most of our LEDs will take an amp for a while without undue stress if the cooling is adequate. That means a 1A fast blow fuse has enough time to open preventing a burn out or a lot of stress to the remaining LEDs.

In reality if you over amp a string, probably one LED will burn-out open and act as a fuse anyway, but I'd rather have a fuse do it. Occasionally LEDs fail shorted like incandescent bulbs that get superdupermegabright for a few seconds after they've actually failed. In that case you could have several LEDs in a string damaged which a fuse should mitigate.

Not paralleling is simpler.
It costs more. It's less efficient. It causes more harmonics. Uses more space. Is heavier. Entails more power cordage. Requires more dimming solution. But it's more straight forward and works. Hence some people choose it. Since our typcial ELN60-48 can reasonably support 2 strings it really makes more cents to add a few bucks of components and do some simple balancing, instead of adding another $30 driver.

Kcress, thank you very much for a very detailed explanation. I learned something new today.

[jpccusa]

Not paralleling is simpler.
Just to paraphrase you, the linear design is simpler, right?

It costs more. It's less efficient. It causes more harmonics. Uses more space. Is heavier. Entails more power cordage. Requires more dimming solution. But it's more straight forward and works. Hence some people choose it.
In this paragraph you are still referring to the linear (simpler) setup, right?

Since our typcial ELN60-48 can reasonably support 2 strings it really makes more cents to add a few bucks of components and do some simple balancing, instead of adding another $30 driver.
Not only one $30 driver, but 2 additional drivers in my case ($60+).

Comparing the efficiency of parallel and linear setups, would I notice any difference in brightness and/or lifespan of the LED's in one vs. the other? Any difference in savings on my electric bill in the long run?

[kcress]

jpccusa; No I am not referring to "linear". Perhaps you have a misunderstanding.

We are referring to a single string verse two or more wired in parallel.

"Linear" refers to the method of current control. Which we aren't discussing..

[jpccusa]

Darn it! I was avoiding jargon at all costs in order to avoid confusion... :)

Anyhow, when I said "linear" I meant "a single string verse two or more wired in parallel."

[jpccusa]

CORRECTION OF POST #1 (see underlined)

Color: 24 XP-E Royal Blue + 14 XP-G Cool White + 8 XP-G Neutral White + 2 XP-G Warm White

CORRECTION OF POST #15 (see underlined)

Not paralleling is simpler.
To paraphrase you, one single string per driver is simpler, right?

It costs more. It's less efficient. It causes more harmonics. Uses more space. Is heavier. Entails more power cordage. Requires more dimming solution. But it's more straight forward and works. Hence some people choose it.
In this paragraph you are still referring to one single string (simpler) setup, right?

Since our typcial ELN60-48 can reasonably support 2 strings it really makes more cents to add a few bucks of components and do some simple balancing, instead of adding another $30 driver.
Not only one $30 driver, but 2 additional drivers in my case ($60+).

Comparing the efficiency of parallel and single string setups, would I notice any difference in brightness and/or lifespan of the LED's in one versus the other? Any difference in savings on my electric bill in the long run?

[TheFishMan65]

kcress, Question for you. How much should we over rate the resistors? At 1 amp a 1 watt resistor will work, but it will probably get awfully warm. Do we really need 5x (a 5 watt resistor) or is 2 or 3 good?

Believe it or not I am having trouble finding a 1 watt 1% 1 ohm from my usual supplier.

Thanks

[BluScrnOdeth]

kcress, Question for you. How much should we over rate the resistors? At 1 amp a 1 watt resistor will work, but it will probably get awfully warm. Do we really need 5x (a 5 watt resistor) or is 2 or 3 good?

Believe it or not I am having trouble finding a 1 watt 1% 1 ohm from my usual supplier.

Thanks

I usually get my stuff from Newark.com (http://www.newark.com). I'll see if i can get the link of what i exactly ordered. But i bought 500 1ohm resistors for about 10 bucks with shipping. The shipping was more than the product which cost about 3.50.

[BluScrnOdeth]

[QUOTE=jpccusa;18307818]My background: I have no experience with electronics and I am somewhat afraid of electricity. I am a business adm student ........QUOTE]

This is basically what i have done with my system. Except i dont have any "constant current regulation" because i am using a PC power supply for my testing. So far, 5 days and holding strong. LED's are staying cool with the aluminum U bar, 1 ohm resistor, fuse, and a voltage regulator (just a little extra caution). I have 12v system, 4 LEDs parallel and 12 strands in series. I think i said that right.

i have bene given a lot of crap for not using something that regulates the current, but everything seems to be running just fine and i havent found any articles online that present any danger to my array of LEDs.

[kcress]

A 2W is fine a 3W a little better. You can't run 1W thru a one watt or it will fail in months. It will also burn you the instant you touch it. A two watt would last indefinitely and would probably be painful to touch but wouldn't burn you. A 3watt would not probably be painful and would again last indefinitely.

If you're running 0.8W (800mA) thru a one watt rather than 1A it will probably last as long as the LEDs. It will burn you if you touch it for any length of time. In all cases we since we're mounting the resistor up in the air suspended between terminal blocks it will be as cool as it could possibly be in an application.

If you are really hung up about the power aspect you can actually use a 0.1 ohm resistor in the 1/4W rating and it won't get warm. But then you have to always multiply the meter readings by 10 which is often another point of confusion for beginners.

[jpccusa]

Believe me, reading this is already confusing enough (not your fault Kress). LOL

I think a 1.0 Ohm, 1% accuracy, 3W resistor will work for my setup then (I will be running the driver at 600 mA)

[jpccusa]

This video (http://www.youtube.com/watch?v=5V6CFa_xKDI) explains more or less my future setup

[jpccusa]

I have questions about the fans I'll be using for cooling the LED's.

I got 2 of these fans

139836

Features:

* The fan glows a fantastic Four color, which adds color and style to any PC system.
* PC Case fan.
* Very quiet 17.5 dB(A).
* Four LED, Blue, Green, Red, Yellow.
* Crystal frame and blades.

Technical Data:

* Frame dimension: 120 x 120 x 25mm
* Fan speed: 1200 RPM
* Fan airflow: 38.4 CFM
* Fan air pressure: 1.17 mm H20
* Fan life expectancy: 20000/hrs 25°C
* Bearing type: Sleeve Bearing
* Connector: 4-pin
* Voltage rating: 12V
* Current rating: 0.15 A
* Noise level: 17.5 dB(A)

My questions are:

1) How can I power those fans? I plan on cutting off the 4-pin connectors. Should I use an old 12V cell phone charger? Would I use one charger per fan or can I connect both fans to the same one?

2) What would be the best way to mount them on my canopy? Remember, my canopy has an open back and an angled frontal lid. I cannot install them vertically inside the canopy (not enough height). Options are:
- On the back, blowing air in OR blowing air out, OR one way each (circulation?)
- Inside, horizontally, parallel to the U-channels, blowing air up, down, or one each.

[TheFishMan65]

What is the current rating on the charger. If > 400ma (leaves room for safety) then you can run both fans.

Is the top of the canopy open? Might be best one in and one out with a divider to make sure the air goes through the whole canopy. Hard to say without seeing it. Pictures?

[bamf25]

kcress do you have your wiring diagram again? I have seen you old version with the ajustable resistors, I like the new fixed resistors you just listed above.

I want to do a 72 led setup so that would be $100 in drivers more, not to mention all the weight. Is there a similar driver that can handle of few more mA or will I just not miss running both strands at essentially 650 mA? I was also looking at the new XL-M's for my whites, these are rated at 3000 mA max, so in theory there is no way the eln-60-48 could blow those since its max mA is 1.3. Just adding a littel something to the fire. Now the XP-E's are max rated at 1000 mA so I would definately fuse those.

Do we have any non scientific RC data on how series vs parallel has gone for thos dyi's done here? I just want to have a nice safe fixture that will not cuase me to lose slepp if I do away for a few days.

[kcress]

bamf25; Don't mix those up. The fixed resistors are only for use with a current driver not the "budget" style build.

The wiring diagram is in the last 10 pages of the "BIG" LED build thread.

Oh, and we shouldn't be hijacking JP's build thread. You have your own build thread don't you? Let's do it in there. :beer:

[BluScrnOdeth]

JPCCUSA

This is what i did for my LED setup. May be a little more risky than others, but from what i understand it is rather safe. I have a 12V PSU. My LEDs vary between 3 and 3.2v because im using XPG and XPE LEDs. SO they require more voltage than the PSU can supply, even if it peaks. So the LEDs are being underpowered by no more than 1V at any given time.

I run 4 LEDs in series, 8 lines parallel. Since the LEDs voltage is underpowered, they arent sucking up all the mA's they can. I have a quick burn fuse inline for each series and one 1ohm resistor for the whole unit (not sure if the resistor is really needed). I have an 80mm Fan cooling off each unit.

The molex connector of the fan has 4 stems. The fan uses the red 5V line and the LEDs use the yellow 12V line. So I just put them all into the same plug and conencted it to the PSU. It worked out really well, allows you to keep things clean with only having to run one cable.

The only thing im trying to do now is build a case for it and dont have any idea on what to do.

[jpccusa]

Is the top of the canopy open? Might be best one in and one out with a divider to make sure the air goes through the whole canopy. Hard to say without seeing it. Pictures?

Here are some pictures and measurements of my canopy.

139945
Top view of canopy with two 120mm fans for comparison

139946
Side view of canopy

139947
Canopy's open back

[TheFishMan65]

Are you willing to cut air vents in the top or front cover?

[jpccusa]

Are you willing to cut air vents in the top or front cover?

I thought about it but I was concerned my entire living room would be lit.

Front cover, no way. Top cover, could be, if no satisfactory alternative solution is available. :)

[TheFishMan65]

Have you seen kcress heat summary? How hot are the LEDs getting, maybe you do not need to do nothing.

[jpccusa]

...

[jpccusa]

I did see that.

And I don't have the LED's yet... waiting for you to buy them for us. Hehehehe

Given the small enclosed space, I would rather install the fans somehow.

I had thought about both blowing air in... OR both horizontally inside the canopy, blowing air up (without making holes on the canopy, if possible).

[TheFishMan65]

Well if you need them, I woud put one on each end. One blowing and the other blowing out. I would then block the rest of the back so the air must go through the whole canopy.

[jpccusa]

Cool... I had thought about it.

Another option I had thought was both blowing air in, rest of the space blocked and an open space in the middle (planning on having 2 sections of LED's. Where the U-Channels break I could do the opening on the back).

Would this work better?

[TheFishMan65]

I don't know you may want to try one and if it does not keep it cool enough try the other.

[jpccusa]

I got the LEDs and drivers yesterday. I will try to take pictures of the building process once I start.

First questions before I start: Based on the following diagram, are those 20 gauge wires (on the left side of the first and last terminal blocks) connecting all positions? Are those called "jumpers?"

146215

[TheFishMan65]

Yes and no. Only enough for the number string you want on that driver. In the picture the block would support ten strings even though 2 are shown. Make sure the driver goes to the right group.

[roundman]

OK I have been following all of the LED threads and looking at using the arduino to control. What size is the fuse on the diagram? I did not see it marked or is it dependent on the amount of leds?

Thanks

[TheFishMan65]

It is dependent on the type of LEDs. Maximum ratings would usually be (if it is a non popular color check the data sheet)
XR-E 1 amp IIRC some are 700ma
XP-E 1 amp
XP-G 1.5 amp
XM-L IIRC 3 amp

[shikhyung]

If you have not cut the U channel yet, then nearby your work their is a metal supply shop. You can choose any style, size?

[jpccusa]

If you have not cut the U channel yet, then nearby your work their is a metal supply shop. You can choose any style, size?

Thanks for the tip. I haven't cut the u-bars yet so I will check them out. Here is their info: Industrial Metal Supply: 2481 Alton Parkway, Irvine - (949) 250-3343

[jpccusa]

Can someone tell me things to be aware of (common mistakes) in order to prevent damage to myself (shocks), the equipment (multimeter, soldering iron), and the LED's (diodes, drivers)?

[TheFishMan65]

Reverse voltage (swapping + and -) is bad
Short to the heat sink is bad
Forgetting to set the multimeter properly for current measurement can blow the fuse.
Static electricity should be avoided

[jpccusa]

It has started...

This afternoon I went to the place Shikhyung suggested and I was able to buy the same U-channels for half the price. SCORE! Thirty two (32) feet was only $20. I was able to return the Home Depot ones.

After returning home I worked on the drivers setup. I attached everything to pieces of plywood that will be attached to the inside part of the aquarium stand.

Some connections are temporary (long wires are required for the permanent setup).

<a href="https://picasaweb.google.com/lh/photo/nz4N9Rkb5jb25NMRSg8JlfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh6.googleusercontent.com/_ytQbgTx0aag/TbJSIoKdv3I/AAAAAAAAHBw/b82p_UAZlUE/s800/IMG_4625.JPG" height="600" width="800" /></a>
Labeled all LED's

<a href="https://picasaweb.google.com/lh/photo/XJm94qZ3ovvSxCAMAVJxyfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TbJR-FYkkUI/AAAAAAAAHBo/ra9fOLd8Wvo/s800/IMG_4627.JPG" height="600" width="800" /></a>
Connected Resistors

<a href="https://picasaweb.google.com/lh/photo/mema6ErPqJUh24M5jRzqifJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TbJSGSz_gWI/AAAAAAAAHBs/JPQuwDtbsO8/s800/IMG_4628.JPG" height="600" width="800" /></a>
Connected fuses

<a href="https://picasaweb.google.com/lh/photo/K-pfvFDOzrzbIg2MV0N3bfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/_ytQbgTx0aag/TbJSOHKxOjI/AAAAAAAAHB0/gNV3RwxfNqs/s800/IMG_4629.JPG" height="800" width="600" /></a>
Connected Pots to DC supply

<a href="https://picasaweb.google.com/lh/photo/X_Mm3pH3KLsyPLP3zPZXdPJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/TbJSWOeC4PI/AAAAAAAAHB8/GPsL5DiYA24/s800/IMG_4631.JPG" height="800" width="600" /></a>
Connected everything to the driver. Terminal block with green jumper is the return, connected to the black wire on the driver and waiting for the return from the LED array.

<a href="https://picasaweb.google.com/lh/photo/So88uqGTSYpqiPzvqjHWvfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/_ytQbgTx0aag/TbJSXyS2x8I/AAAAAAAAHCA/iC_9aBCvnr0/s800/IMG_4630.JPG" height="800" width="600" /></a>
The entire setup

<a href="https://picasaweb.google.com/lh/photo/r5EcbNWVLeDIPXPwSzS_bPJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/TbJSbAZ21LI/AAAAAAAAHCE/ExRlxNzb5wY/s800/IMG_4633.JPG" height="800" width="600" /></a>
Different angle

Any suggestions? Anything alarming?

[kcress]

:thumbsup:

I'm not a big fan of anything electrical mounted to wood.

That said, it sure is convenient. You should have no problems with your setup. It looks like you fully grasp all the details.

Thanks for the nice pictures.

[jpccusa]

Baffled!

After doing all the soldering and connections (and double checking everything) I turn on the wall wart and 1 of the drivers (the whites)... Only 5 LED's turned on, one of them being a blue (???).

I removed the wall wart from the power supply and the LED's were still on.

Can anyone tell me what's going on based on this description?

[jpccusa]

Okay... found a function on the multimeter that tells me when there is a short. Found the short and re-soldered, which solved the problem.

Increased the pots and all is working now.

Going to readjust the pot to 700mA.

Pictures coming soon.

[jpccusa]

Whites are at 600mA one string, 594mA the other. SCORE!
Blues are very different (one string at 609mA and the other at 453mA). Now I have to check each individual LED to balance them.

[jpccusa]

Darn... while checking the RB LED's, one of them shorted out (closed). I don't understand how it happened but now I'm afraid of checking the rest (all remaining LED's remained lit).

I had the multimeter set to measure volts, then I touched the + side of the LED with the red probe and the - side with the black probe while the entire system was on.

What did I do wrong?

[jpccusa]

Here are some pictures from yesterday and today.

<a href="https://picasaweb.google.com/lh/photo/5eSiNZCgLNGHMsoKiZ4z3_JgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/_ytQbgTx0aag/TbUIqBymclI/AAAAAAAAHCo/qihz4vD8xYc/s800/IMG_4635.JPG" height="600" width="800" /></a>
U-channel frame.

<a href="https://picasaweb.google.com/lh/photo/F22pe5-9CQi37nyU_mLOOvJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh6.googleusercontent.com/_ytQbgTx0aag/TbUI6HzMGzI/AAAAAAAAHCw/UF3jCKLPca0/s800/IMG_4637.JPG" height="600" width="800" /></a>
Four channel. Smaller one is actually going on the lid of the canopy (change in plans).

<a href="https://picasaweb.google.com/lh/photo/D4LYIdJ7VZSpYfGS0gTPOPJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/TbUJaClvFYI/AAAAAAAAHEE/5BKV6C-G-hM/s800/IMG_4642.JPG" height="800" width="600" /></a>
Used 96 of those to secure all LED's in place.

<a href="https://picasaweb.google.com/lh/photo/L4VuQdIjye52WhlJvLaZCPJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/TbUJLfh2Q_I/AAAAAAAAHDA/JWPQYRUj_lI/s800/IMG_4641.JPG" height="800" width="600" /></a>

<a href="https://picasaweb.google.com/lh/photo/8IUr4TQQmZ9qVzq9QyP9lPJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/_ytQbgTx0aag/TbUJNMwGxRI/AAAAAAAAHDE/MCHf523H_LE/s800/IMG_4640.JPG" height="600" width="800" /></a>

<a href="https://picasaweb.google.com/lh/photo/ck3x2Q-dX4om3SAT7LX19fJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/_ytQbgTx0aag/TbUJdWLVNUI/AAAAAAAAHDw/Cont-fQpqrE/s800/IMG_4644.JPG" height="800" width="600" /></a>
Today I connected the wires. Green for the RB and red for the whites.

[TheFishMan65]

And before some asks. In the second picture from the bottom whit is one LED different. It is a neutral white rather than cool. They came from a different supplier.

[jpccusa]

Those are harder to solder. The solder almost doesn't want to attach to the LED. One of those NWs was the one shorting the system as well (post#49 or 50). It was weird because all I had to do to solve the problem was resolder the connection.

I still need help figuring out what went wrong yesterday (post#52) and how I measure Vfs on the LED's. The RBs strings are REALLY different. After burning one LED, I lowered the driver's pot all the way, didn't try to measure LED's Vfs anymore (waiting for instructions) and just measured the current on both strings. One is at 15, the other at 248. One string is dim, the other brighter.

[TheFishMan65]

I had 5 go and don't know why? Hmm maybe I had one short to the heatsink and when I tried to test an LED I made second short to the heatsink. The driver for a few nanoseconds would overdrive the voltage at what it was for more LEDs and maybe spike the current.

So the way to measure the voltage of each LED is uing the +/- of each LED. Just make sure you don't short anything.

[jpccusa]

So I was doing it right, probably just touched the screw? Darn.

1) What is the value I should see for each Vf? Would it be in the 3V area?

2) Can you guess why such a huge difference between the 2 strings other than very different Vfs for each LED?

[TheFishMan65]

Vf depends on current the approximate value if found in the chart in the datasheet.
Could be poor solder joint which caused an increase in resistance. When I measure Vf I measure from the adjacent stars so the solder terminals are also measured.

[jpccusa]

* * * Duplicate - see below * * *

[jpccusa]

When I measure Vf I measure from the adjacent stars so the solder terminals are also measured.

So you put the red probe on the available positive terminal of one star, and the black probe on the available positive terminal of the next star (in order to avoid the soldered terminals). Is this correct?

[TheFishMan65]

That would measure the solder joint. This is what I was thinking

-LED+ wire -LED+ wire -LED+ wire -LED+ wire -LED+ wire
......................P......................P
Place the probes where the P are located in the chain. This measure the Voltage of the LED and both of it's solder joints.

Apparently neither of us was very good at Operation as a child:lol:

[kcress]

Fish has it just right. If you want to measure the "situation" of one LED you measure it on the adjoining LEDs. Not on the LED itself as you otherwise completely miss the soldering which is the most likely issue.

Also, you should never come back here with some sad story about a short!

There is no reason to ever turn on a build to discover shorts. You discover them before you turn on the power with your meter! Doing it with power is how you damage a lot of stuff.

Once you step thru your entire string(s) using your 'diode test' setting to light each diode from the neighboring LEDs successfully, you then use the ohms setting and measure from the heatsink to one of the soldered pads between each LED. You only need to do one side because you did the previous test which confirmed both sides are properly soldered.

Once you've done this and before you power up for the first time you always turn the current limit pot down all the way. This protects from wildly different string Vfs.

[jpccusa]

Part of my problem is not even understanding the tool which would help me do all the measurements and checks (multimeter).

When I tried measuring the system without powering it on, all I got was 0 (zero). I figured I needed power in order to have readings.

Good thing I had the current limit pot down all the way (on the driver).

Question: without powering the system, will I be able to do the Vfs readings?

[katchupoy]

Part of my problem is not even understanding the tool which would help me do all the measurements and checks (multimeter).

When I tried measuring the system without powering it on, all I got was 0 (zero). I figured I needed power in order to have readings.

Good thing I had the current limit pot down all the way (on the driver).

Question: without powering the system, will I be able to do the Vfs readings?

Limited knowledge here...

But when powered down. You can check continuity of the circuit.

To check for VFs, it should be powered up.

[kcress]

jpccusa; Show us what meter you have.

[jpccusa]

Alright, I just got home from work and I'm ready to finalize this baby.

Here it goes Kcress.

<a href="https://picasaweb.google.com/lh/photo/ldxxTDfDbxAXHsjXCjaEXvJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/TbYASqfo4zI/AAAAAAAAHEs/udXP5NMNFlI/s800/IMG_4645.JPG" height="800" width="600" /></a>

<a href="https://picasaweb.google.com/lh/photo/q4wcZtBsxWZHB74L_RYxkvJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/_ytQbgTx0aag/TbYARtDnaBI/AAAAAAAAHEo/AvW7442lY8o/s800/IMG_4646.JPG" height="600" width="800" /></a>

[jpccusa]

These are the fans installed on the canopy

<a href="https://picasaweb.google.com/lh/photo/1DTXqFldl6r_YO1T_eAcrfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TbYK3sky2sI/AAAAAAAAHFM/Cn0G-qAyaoc/s800/IMG_4647.JPG" height="800" width="600" /></a>

<a href="https://picasaweb.google.com/lh/photo/-ADgZjEzPnAiKFhxmJeaT_JgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/_ytQbgTx0aag/TbYK40cyqkI/AAAAAAAAHE8/Jd4KNA7Jy8k/s800/IMG_4648.JPG" height="600" width="800" /></a>

The aluminum channels installed on the canopy will hold the LED setup. It allows me to slide the lights back and forth (easier for cleaning the tank).

[freetareef]

sweet keep the pics coming!!! nice job.

[jpccusa]

Okay, I nervously got some numbers.

Line 1: (3.02)(3.04)(3.04)(3.03)(3.01)(3.03)(3.03)(3.01)(3.00)(3.10)(3.15)
Line 2: (3.02)(2.95)(3.02)(3.10)(3.04)(3.27)(3.20)(3.02)(2.95)(3.18)(3.04)

The above numbers were measured using adjacent LED's, multimeter dial on position 20 (at about 10 o'clock on dial). There are only 22 LED's because one burned. I removed one good LED from the other line so both lines have the same quantity.

Line 1: 655
Line 2: 404

The above numbers were measured across the resistors of each line, multimeter dial on position 2 (at about 9 o'clock on dial).

Measurements were taken with the system turned on and driver's internal potentiometer dialed to 650 on line 1 since that was the highest line.

1) I don't understand why I get a very low reading when trying to do the same measurement across the fuse.

2)Also, regarding the fuses, is there a problem I inverted their order and put them AFTER the resistors in the lines?

3) Since there are a lot of temporary connections, will measurements change once I solder the permanent cables?

[kcress]

Those meter pics are good. Thanks.

Set your meter to diode test. That's the funny symbol on "2K".

Then measure an unpowered LED with it. Stick it across the two LED soldered wires. Look at the LED as you do this. Try it reversed too.

One way should light the LED dimly. Note the polarity that works. Try it and get back to us.

[TheFishMan65]

1) Low reading on the fuse is because it has low resistance (ideally zero) voltage = current * resistance. If if zero resistance zero voltage drop

2)No order does not matter in this case

3)Yes, but probably not by much

If my math is correct the upper string is 33.46 volts and the lower is 33.79. Can you measure across the whole string and see if that holds true. If it is a solder joint might be further out at the resistor, fuse or connection to the meanwell.

[jpccusa]

Those meter pics are good. Thanks.

Set your meter to diode test. That's the funny symbol on "2K".

Then measure an unpowered LED with it. Stick it across the two LED soldered wires. Look at the LED as you do this. Try it reversed too.

One way should light the LED dimly. Note the polarity that works. Try it and get back to us.

Yesterday I checked the unpowered LEDs with the continuity test (alarm symbol on red area at 5:30 of dial) and I saw each one of them dimly turn on. I will try the diode test when I get home today.

In the meantime, what do you mean by "stick it across the two LED soldered wires"? Do you want me to probe the wires leading in (+) and out (-) of the tested LEDs, the + and - solder joints, the unsoldered + / - terminals of the LED being tested, or the adjacent LEDs?

1) Low reading on the fuse is because it has low resistance (ideally zero) voltage = current * resistance. If if zero resistance zero voltage drop
Makes sense now.


2)No order does not matter in this case
Whew! :thumbsup:

3)Yes, but probably not by much

If my math is correct the upper string is 33.46 volts and the lower is 33.79. Can you measure across the whole string and see if that holds true. If it is a solder joint might be further out at the resistor, fuse or connection to the meanwell.

I will do that measuring once I get home. I will put one probe on the unsoldered positive terminal of the first LED, and the other probe on the unsoldered negative terminal of the last LED, right?

I did not understand your statement "If it is, a solder joint might be further out at the resistor, fuse or connection to the meanwell." I guess we can wait and see if the measurements and your math match before we worry about this statement.

[TheFishMan65]

That measure the LEDs voltage. What does the resistor and fuse add? What is the voltage coming out of the Meanwell?

[jpccusa]

Kcress, here are the pictures of the test.

<a href="https://picasaweb.google.com/lh/photo/6f2wPbYCOs3YaWaucybGmvJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/_ytQbgTx0aag/TbdRgpDCQBI/AAAAAAAAHFk/yUL8WgzgKwE/s800/IMG_4651.JPG" height="600" width="800" /></a>

<a href="https://picasaweb.google.com/lh/photo/FkdHxZ_6Kiv7plCQz1shvfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TbdRkGzvnaI/AAAAAAAAHGE/2iToupeG1H8/s800/IMG_4649.JPG" height="600" width="800" /></a>
Detailed

<a href="https://picasaweb.google.com/lh/photo/5AcaGDcNy8XYlTE6DTTu6PJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TbdRjpOtz7I/AAAAAAAAHFo/X60OmCAKHTk/s800/IMG_4650.JPG" height="600" width="800" /></a>
Inverted probes

FishMan, reading from the driver + (where the blue jumper is) to the driver - (where the green jumper is), I get a reading of 34.5

Reading line 1 from LED1 to LED11, I have 33.9
Reading line 2 the same way, I have 33.6

[kcress]

Ah, most excellent!

Two things to do.

Do exactly what you are showing EXCEPT do not use the pads for the LED you're checking. Probe the other ends of the two wires that come to LED you are testing.

You have to do this so you test the actual solder joints on the LED of interest.

Do this test on every single LED. Bang bang bang bang. On a big build it might take 3 measly minutes.

That took another 3 minutes. It takes a lot less time than it took me to type this.. :hmm3:

As you rocket down all the chains make sure the polarity is what you expect. It has to be the same all the way down the string. You should see the pattern right away and be able to just hop from LED to LED.

That was the continuity test.

The other test is a shorted wire test.
This time probe a LED exactly as you show in your first two probe pictures. Exactly.

Once you see the LED light up you leave one probe on the pad. You move the other probe off the pad and onto one of the screws - only one - you don't need to do both. (This is to make sure you're touching the aluminum because sometimes it's anodized and hence insulated but screws always cut thru that.)

If with a probe on the screw/heatsink the LED lights the solder joint, wire, or a screw is shorting out LED drive current to the heatsink.

Because there are two LEDs and two solder connections on each wire the short could be on the neighboring LED or the LED you're testing.

If when you moved the one probe to the screw the LED correctly did NOT light up, return the probe to the LED pad and confirm the LED lights up. THEN move the other probe off the pad and onto a screw. This tests the other side for a short to the heatsink.

[jpccusa]

Kcress,

CONTINUITY TEST: All LED's lit up, individually, as expected.

<a href="https://picasaweb.google.com/lh/photo/IDONhW0Y_5QNuNjSi4h5OfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/Tbe-ey_mhRI/AAAAAAAAHHU/9fNtnPsF7OU/s800/IMG_4654.JPG" height="600" width="800" /></a>
Hard to see but the probes are touching the wire close to the adjacent LEDs solder joints.

SHORTED WIRE TEST: All LED's did NOT lit up when I switched the probes (independently) to the screws.

<a href="https://picasaweb.google.com/lh/photo/I5TeJ4AoaySd8FStSfRUWPJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/Tbe-nwV6E8I/AAAAAAAAHHg/2S_FFR7jTwk/s800/IMG_4655.JPG" height="800" width="600" /></a>
Initial position

<a href="https://picasaweb.google.com/lh/photo/NAsCK5P8F2zRN-W8c1H00PJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/Tbe-qfe6bMI/AAAAAAAAHHk/yrKIcfMQcGo/s800/IMG_4656.JPG" height="800" width="600" /></a>
Move red probe to screw

<a href="https://picasaweb.google.com/lh/photo/IAYUUFmhV26JiEbZ5f1lM_JgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh6.googleusercontent.com/_ytQbgTx0aag/Tbe-xHDengI/AAAAAAAAHHo/KKesG8vHn8k/s800/IMG_4658.JPG" height="800" width="600" /></a>
Move red probe back checking LED works

<a href="https://picasaweb.google.com/lh/photo/bpqBQvFcLkrPr_sZC5gr1vJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/_ytQbgTx0aag/Tbe-6AiwIpI/AAAAAAAAHHs/A3FSOpCf69c/s800/IMG_4657.JPG" height="800" width="600" /></a>
Move black probe to screw

It really took me less time to do both tests on all LEDs than it took you to write me the instructions. I really appreciate your help and time (same goes to FishMan and others) this far! Please stick around since I'm still not done. LOL

NOTE: I hope people find this thread ridiculously easy to understand and follow. I am taking advantage of the fact I am not knowledgeable in electronics/electricity to visually document all the steps of the entire process.

[kcress]

Damn! Someone who can follow instructions perfectly! :love2:

Excellent pics too. Bravo.

So. All tests done. All Passed.
This means NO assembly errors.

Is there still a problem?

[jpccusa]

The two white strings (red wires) work perfectly. Their measurement across the resistor is almost identical.

For the blues (green wires), there is a huge difference between the two strings. Please see post #69 (http://reefcentral.com/forums/showpost.php?p=18693773&postcount=69) for some numbers.

I am not sure I am measuring correctly in order to have the parallel strings balanced.

Fishman was helping as well, and he addressed the three questions from post #69.

I posted some results at the end of post #74 (http://reefcentral.com/forums/showpost.php?p=18693773&postcount=74) as well.

[Algaenot]

Kcress – Outstanding testing description. There are many of us that do not have the experience with electronics and having someone who is willing to describe the process at a very basic level is much appreciated. Your patience and willingness to take the time to help novices like myself should be applauded.

[Pro X]

Very good pics by jpccusa with very easy to follow instructions with what to expect and what's wrong if something else occurs by kcress. All this in the first 3-4 pages.......priceless.

[jpccusa]

Kcress – Outstanding testing description. There are many of us that do not have the experience with electronics and having someone who is willing to describe the process at a very basic level is much appreciated. Your patience and willingness to take the time to help novices like myself should be applauded.

AMEN!!!

Very good pics by jpccusa with very easy to follow instructions with what to expect and what's wrong if something else occurs by kcress. All this in the first 3-4 pages.......priceless.

Thanks, and if you set your user controls to display more posts per page, that will make this thread only 2 pages long so far. :idea: :D

I must add that Kcress' instructions are not meant to correct something that went wrong. His instructions are meant to prevent something from going wrong.

I jumped the gun, didn't check for continuity and shorts, and ended up with one less LED. Do these tests before plugging the driver(s) into the electricity!

[kcress]

Algaenot, Pro X; Thanks for the kind words. Thanks for the.. thanks.

I will be pointing a lot of people back to this thread because jpccusa's pictures are perfect.

And yes! Do those tests before the first power-up. I do them before I even bother installing the drivers.

OK, so your blue strings are imbalanced. We can fix that. It seems about 1 in 4 builds has a notable imbalance that would need to be corrected.

Alrighty then. Some info on this. Keep in mind that the Vf of any LED is a function of the current thru it. So when you measure the Vfs of individual LEDs you can't really compare Vfs across two parallel strings - since they don't have the same current running thru them.

So lets look at your numbers jpccusa:

Okay, I nervously got some numbers.

Line 1: (3.02)(3.04)(3.04)(3.03)(3.01)(3.03)(3.03)(3.01)(3.00)(3.10)(3.15)
Line 2: (3.02)(2.95)(3.02)(3.10)(3.04)(3.27)(3.20)(3.02)(2.95)(3.18)(3.04)

The above numbers were measured using adjacent LED's, multimeter dial on position 20 (at about 10 o'clock on dial). There are only 22 LED's because one burned. I removed one good LED from the other line so both lines have the same quantity.

Line 1: 655
Line 2: 404

The above numbers were measured across the resistors of each line, multimeter dial on position 2 (at about 9 o'clock on dial).

Measurements were taken with the system turned on and driver's internal potentiometer dialed to 650 on line 1 since that was the highest line.

Your numbers 655 and 404 should actually be 0.655 and 0.404. They represent 655mA and 404mA when measured across a 1.0ohm resistor.

Once you've made your list of the individual LED Vfs examine both lists. In the high string (655mA) find the lowest recorded Vf. That will be the "3.00" one. This represents the LED doing the most to increase the current in this string.

In the low string find the highest Vf. "3.27" This represents the LED that is doing the most to reduce the current in this string.

Of course power down...

Remove and swap these two LEDs. This will automatically cause the high current string to draw less current and the low current string to draw more current. It will drive the two string currents together.

Please give it a shot and let us know how that one swap changes the currents.

If the current imbalance is still more than 50mA refer back to your two lists and take the next low/high pair and swap them in the same direction. Then re-check. There is no way to calculate this, you have to do single pair swap and checks.

Don't forget to do the Continuity Check and the Short Check on the two LEDs you swap each time. You don't want to have a bad solder job blowing LEDs or fuses.

[Algaenot]

Agree on the excellent pics. jpccusa must have a forehead mounter camera.

[jpccusa]

Kcress: Will do. I thought that was the correct way of doing it, but the math in my head was not making sense.

Was the multimeter settings right to make the LED and strings measurement? I thought to find the mA I would need to use the DC Amps (2 to 5 o'clock on the dial). Will I ever use those functions?

Algaenot: I have a helper who holds the probes while I take the pictures.

[kcress]

To use the DC amps to measure the current you must change the lead plugin on the meter and break the wires and insert your meter. A real pain in the butt and not without risks. You measure the voltage across the resistors that you should have installed with the fuses.

[jpccusa]

Alright, more pictures...

First I unsoldered and removed both (3.27) and (3.00) from their strings.
<a href="https://picasaweb.google.com/lh/photo/bNMzNDR40ssbIgP5Zpa5p_JgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TbisA0MHguI/AAAAAAAAHIQ/g5igSJcYHhw/s800/IMG_4663.JPG" height="600" width="800" /></a>
<a href="https://picasaweb.google.com/lh/photo/z_JPqDesPC6INVF8lnvrjfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh6.googleusercontent.com/_ytQbgTx0aag/TbirmBcBWLI/AAAAAAAAHIA/ex2IBSl7sls/s800/IMG_4660.JPG" height="600" width="800" /></a>

Then I reapplied thermal compound and reattached the LEDs, making sure I swapped their positions.
<a href="https://picasaweb.google.com/lh/photo/9njVadwp_coR_4u4Q4HYrfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/Tbir2O225qI/AAAAAAAAHIM/743JEZxWV-A/s800/IMG_4662.JPG" height="600" width="800" /></a>

This is the thermal compound. If you are going to do parallel, I recommend something that won't set (glue) your stars down. Screws and this worked perfectly. And this compound was cheap too (I will put a price list together once I am completely done).
<a href="https://picasaweb.google.com/lh/photo/cxd2-di289UdpqcdnGTZZvJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/TbirzeqrE9I/AAAAAAAAHII/-jBqtaqmIPM/s800/IMG_4661.JPG" height="600" width="800" /></a>

Anyway, checked for continuity and short. All good. :thumbsup:

Powered on and measured both strings across the resistors:
Line 1: 485
Line 2: 574

A little better, but still too far apart.

Repeated the process with the next highest and lowest pair, which was (3.20) from line 1 and (3.01) from line 2.

Checked for continuity and short. All good. :thumbsup:

Powered on and measured both strings across the resistors:
Line 1: 543
Line 2: 516

Adjusted the driver's internal pot to about 650 using line 1 as measurement (highest of the two).

Final measurement:
Line 1: 663
Line 2: 630

Powered on the whites and measured across the resistors:
Line 1: 649
Line 2: 643

The difference on the whites is 6mA and 33mA on the blues. I think I'm DONE!!!! :bounce2::bounce1::bounce3:
<a href="https://picasaweb.google.com/lh/photo/nJymoevmv3M_oGCYK2kwsPJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/_ytQbgTx0aag/TbisVeceBAI/AAAAAAAAHJI/cl_YKLr2S_8/s800/IMG_4664.JPG" height="800" width="600" /></a>

(Kcress? Am I?)

[kcress]

No! Your fixture is useless on the floor, you have to hang it... :D










Congrats! Well done! :beer:


One more bit of data, that would be really nice for my research, would be to crank up the current all the way and measure the two string currents.
(Don't forget to put it back!)

I'm trying to get a feel for how high the MWs will go if we aren't pushing the voltage limit at the same time.

The data sheet sez 1.3A but I always seem to see much higher than that.

Hey! What are you taking your pictures with and what are you doing to them if anything?

[jpccusa]

No! Your fixture is useless on the floor, you have to hang it... :D

Congrats! Well done! :beer:

Thank you. It would be almost impossible to do this project if I didn't have the support here.

One more bit of data, that would be really nice for my research, would be to crank up the current all the way and measure the two string currents.
(Don't forget to put it back!)

I'm trying to get a feel for how high the MWs will go if we aren't pushing the voltage limit at the same time.

The data sheet sez 1.3A but I always seem to see much higher than that.

This is not a joke, right? I can turn the MW internal pot all the way up (pass specification), make some measurements, and turn it back down without the risk of damaging anything?

Hey! What are you taking your pictures with and what are you doing to them if anything?
I'm taking my pictures with a Canon PowerShot SD750 (http://www.photoxels.com/canon-sd750.html)

The pictures are on a Picasa web album (PM sent).

[jpccusa]

PRICE LIST

* 50 LEDs + 8 fuses + 8 resistors + 8 terminal blocks + 2 drivers + 1 wall wart + 2 pots = $275.90 shipped (Group buy)
* Multimeter = $20 shipped (Ebay)
* Thermal Compound = less than $10 shipped (can't find the receipt)
* 2 Computer Fans + 12v wall wart = $15 (Ebay + Fry's)
* 18 ft. Aluminum Channel = $20.55 (Industrial Metal Supply Co.)
* 90 ft. #22 wire (3 colors) + Soldering Iron + Solder + Desoldering Braid = ~$25.00 (RadioShack)
* Hardware = ~$20.00 (HomeDepot)

Total Cost = ~$386.50 spent along ~ 6 months (my first purchase was the multimeter back in October of 2010)

[chris023]

Great job!!!

I am getting close to this point in my build and was wondering if a picture/clear explanation of "measured across the resistors of each line" is done.
I understand that it is to measure the forward voltage of a string, but am not sure where to put the probes?

appreciate it, thanks.

[jpccusa]

Hello Chris023,

Here is a picture
<a href="https://picasaweb.google.com/lh/photo/OClGJgwyvlGzm7wciq-a6_JgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/Tbjb6pc0MmI/AAAAAAAAHJc/t8dsJGfvCDg/s800/IMG_4670.JPG" height="600" width="800" /></a>

After you make that measurement, move both probes to the other string (above string in the picture) and make the measurement.

Good luck with your build.

[chris023]

great, thanks... doesn't matter which sides the probes go on right?

[jpccusa]

great, thanks... doesn't matter which sides the probes go on right?

I don't think so, but when in doubt, do like the picture. The current was going from the right to the left.

[kcress]

Thank you. It would be almost impossible to do this project if I didn't have the support here.



This is not a joke, right? I can turn the MW internal pot all the way up (pass specification), make some measurements, and turn it back down without the risk of damaging anything?


I'm taking my pictures with a Canon PowerShot SD750 (http://www.photoxels.com/canon-sd750.html)

The pictures are on a Picasa web album (PM sent).


Thanks for the info. That PowerShot continually impresses me.

No! Not a joke. If you're using ELN60s you can't get much over 650mA per string with two in parallel. That's according to the data sheet. But, I always see 700mA or 800mA because the ELN actually seems to put out more like 1.5A not 1.3. I want to know if yours do the same thing.

It won't hurt anything. Just put your meter across the higher string and crank up the pot. Don't force it AT ALL. As soon as there is the slightest turning resistance stop. Note the current and then note the other string's current. Then turn it back down where you want it.












chris023; It doesn't matter which probe goes on which side of the resistors. HOWEVER one way will give you a negative number and the other a positive. Just ignore the sign as it only tells the direction of the current. which matters not in this case, since it flows only one way - the way that lights the LEDs.

[Isayso]

https://lh5.googleusercontent.com/_ytQbgTx0aag/Tbe-ey_mhRI/AAAAAAAAHHU/9fNtnPsF7OU/s800/IMG_4654.JPG


Hi Jpccusa
are those U channel still 3/4" or did you switch for the 1" ones
thanks..
PS:
nice built I need to be kicked in the arse and start mine LOL

[jpccusa]

Those are 3/4" u-channels, identical to the HomeDepot ones from the beginning of this thread.

Report on Temperature: Yesterday I left the LEDs on for over 2 hours, same position as in the picture above (no convection on the channels), and I was still able to touch the aluminum for an indefinite amount of time. I bet once they are hung and with the two fans blowing, they will be barely warm.

Great thing I got talked out of the heavy and expensive heatsinks. They do an excellent job dissipating heat, but in my case, they would be overkill. Heck, even my fans I am thinking are overkill now.

Thanks for the compliments and GET YOUR PROJECT GOING (and don't forget to take pictures)!

[Isayso]

Hi thanks for the answer
I found 3/4" 1/8 and 3/4" * 1/8 thickness. ..any preference?
Or they are all the same
Thanks again

[jpccusa]

IIRC, thicker is better.

[chris023]

Thought I would post this question here, as there is so much good info on meters/testing.

I have a different meter (pic below), and am wondering which settings to use for testing forward voltage of individual LEDs, as well as string (from resistor). I believe 20 (individual) and 2 (string) were used on jpccusa's meter, and there is no 2 on my meter.

Thanks.

http://i977.photobucket.com/albums/ae255/cpschuetze/Aquarium/LED%20Build/018.jpg

[jpccusa]

I believe 2000m is the same as 2 (the m I believe means milli, or 1000)

[jpccusa]

Kcress, I have pictu... I mean, numbers for you. ;)

First set was measured with cold LEDs (just turned on):

<a href="https://picasaweb.google.com/lh/photo/LUg1Je13s-JCT03BpOHEfPJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TboNvrvKPKI/AAAAAAAAHMU/Yd9sjBxCAbk/s800/IMG_4678.JPG" height="600" width="800" /></a>
Blue string 1

<a href="https://picasaweb.google.com/lh/photo/dweMKgFF-y7aRkwkIw1QBfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TboN8LpwMrI/AAAAAAAAHKU/iCq0gnBPdsc/s800/IMG_4679.JPG" height="600" width="800" /></a>
Blue string 2

<a href="https://picasaweb.google.com/lh/photo/WaAOhwrYwxbSqnoOJLqwT_JgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TboO8hqqfQI/AAAAAAAAHMw/wVxklxaFFNs/s800/IMG_4680.JPG" height="600" width="800" /></a>
White string 1

<a href="https://picasaweb.google.com/lh/photo/0zRngm7H4MAzwTbY8qaC8_JgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/TboPNzI33uI/AAAAAAAAHM8/LU9eyYoWYb8/s800/IMG_4681.JPG" height="600" width="800" /></a>
White string 2

I then waited two hours for the LEDs to warm up, then read again, same order:

<a href="https://picasaweb.google.com/lh/photo/qrnD7RGaEnc2GY3kTsHRfvJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/TboPYWaJpBI/AAAAAAAAHNQ/AtEYPd4oOsk/s800/IMG_4685.JPG" height="600" width="800" /></a>

<a href="https://picasaweb.google.com/lh/photo/lcM36pGL0c0hxEXmLvOQ3PJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TboPjVgLRCI/AAAAAAAAHLQ/ZUdfLg9pov0/s800/IMG_4686.JPG" height="600" width="800" /></a>

<a href="https://picasaweb.google.com/lh/photo/nMZ4Wl5PnWg4uk-h52xhbfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TboPqSOPWaI/AAAAAAAAHLU/3NKnUCbC_ew/s800/IMG_4687.JPG" height="600" width="800" /></a>

<a href="https://picasaweb.google.com/lh/photo/JzVN5qqSas0zmE9DvBeSnvJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/TboPuJOGVhI/AAAAAAAAHLc/jBmBVSkuNrc/s800/IMG_4688.JPG" height="600" width="800" /></a>

Notes: 1) Tried taking picture of the difference in brightness, but the camera self adjusts and they look the same.
2) At a certain point, the driver's internal potentiometer keeps turning but the numbers no longer increase.
3) Interesting to see that some numbers went up after warming up, while other numbers went down.

I hope this helps Kcress. Time to hang those babies!

[kcress]

WoW! That means those MWs put out about 2.0A not just 1.3A. At least that's while running 11 or 12 LEDs. That probably wouldn't be the same with more LEDs crowding the ELN's maximum output voltage.

Great info. Thanks again. Yes! Hang those suck'ahs.

[jpccusa]

Does that mean I can raise the internal pot without any side effects?

BTW, I hung them, but ran out of wires to make the long distance connections.

<a href="https://picasaweb.google.com/lh/photo/_EFCgo9J-_HSvXnyUTgkK_JgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh6.googleusercontent.com/_ytQbgTx0aag/TbpMsXtmzHI/AAAAAAAAHNo/ez9xE__T79Y/s800/IMG_4689.JPG" height="600" width="800" /></a>
Detail of how I used the U-channels to also be the support for the array.

<a href="https://picasaweb.google.com/lh/photo/Dh__IpWdXOj-zBSji_XnfPJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh6.googleusercontent.com/_ytQbgTx0aag/TbpM3Xb6zxI/AAAAAAAAHNs/9A1LYOts7-4/s800/IMG_4690.JPG" height="600" width="800" /></a>

<a href="https://picasaweb.google.com/lh/photo/_x81kFM64c-3OeSTUi7rdvJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/_ytQbgTx0aag/TbpM61md3SI/AAAAAAAAHOM/AGvvXTEzcS4/s800/IMG_4692.JPG" height="800" width="600" /></a>
Detail of how I used corner braces inside the canopy to support the pots

<a href="https://picasaweb.google.com/lh/photo/BGedtsDmKQt_22BUMHUJNfJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh5.googleusercontent.com/_ytQbgTx0aag/TbpNIYzd7PI/AAAAAAAAHN8/sZtaatlg7o8/s800/IMG_4694.JPG" height="800" width="600" /></a>
Kitties have new decoration in their dinning area. :wildone:

[kcress]

Kitty, kitty, kitBIZZZZZZAP!

Nice touch with the slide in fixture.

It means you can probably turn things up to about 750mA a string instead of just 650mA per string. That is, if nothing gets too hot.. Under an open cabinet it will probably be fine. In some hot enclosure, maybe not so fine.

[vietcu]

Great write up JPC, I am going to have to convert my build to Parallel instead of using all 6 Meanwells. Look for some PMs soon :).

[vietcu]

I got these resistor and fuse from a local shop. Will it work for the parallel setup?
http://i960.photobucket.com/albums/ae88/fishamore/IMG_1682.jpg
http://i960.photobucket.com/albums/ae88/fishamore/IMG_1683.jpg

[kcress]

Absolutely!

[Coppertop412]

OK, I've read and re-read this thing and I know I'm missing some little step.
I have 2 strings of 12 XP-G cool whites, one is WAY brighter than the other, but when I measure voltage from the positive of the first to the negative of the last the dim string is 30.03, the brighter is 29.97. I can't find any shorts. Do I need to check voltage of each LED?
The resistors I got at Radio Shack are 1-Ohm, 10 Watt, are these OK?
Sorry to hijack your thread, but I can't seem to figure out what simple thing I'm over looking!

[Coppertop412]

Also, if i turn the dimming pot all the way up my readings go to 33.2 on the dim one and 33.7 on the bright one.
HTH

[SC Reefaholic]

Dont know how they relate as I am certainly not an electronics guy but sounds like a current issue. Have you put your meter inline and measured mA that each string is receiving? Dont know why they would be different but thats what it sounds like.

[jpccusa]

OK, I've read and re-read this thing and I know I'm missing some little step.
I have 2 strings of 12 XP-G cool whites, one is WAY brighter than the other, but when I measure voltage from the positive of the first to the negative of the last the dim string is 30.03, the brighter is 29.97. I can't find any shorts. Do I need to check voltage of each LED?
The resistors I got at Radio Shack are 1-Ohm, 10 Watt, are these OK?
Sorry to hijack your thread, but I can't seem to figure out what simple thing I'm over looking!
Also, if i turn the dimming pot all the way up my readings go to 33.2 on the dim one and 33.7 on the bright one.
HTH

Okay, as you could see on my thread, I was the one asking questions, so I may not be the most appropriate person to answer yours.

Hopefully one of the people following this thread will chime in as well.

Anyway, the resistors you got are 10W. The ones Kcress recommends is 3W or 5W. Have you measured how much current is passing through them? If so, what do you get for each string?

In my setup, there are 2 types of potentiometers: the drivers ones (what I called internal pots at times) and the wall wart ones. The wall wart ones I turned all the way up. The internal ones I turned all the way down. That's to start.

Do all the tests Kcress said (continuity and short). If all goes well, plug the drivers and wall wart. Measure the current across the resistors for each string and note the numbers.

And don't worry about highjacking as long as your setup is similar to mine. :)

[Coppertop412]

I was hoping Kcress would chime in, maybe I should shoot him a PM?
I have tested everything he recommended for you. I'm getting .070 A on one, and .390 on the other. (same resistors on both, even switched them around and problem stays with the string).
I have my pots set the same as you (dimmer to max, internal minimum).
I'm just about ready to go with the original plan of 13 per string, 1 string per driver!
I just know there's 1 simple thing I'm overlooking.

[kcress]

The wattage of the resistors is absolutely unimportant as long as they're over a watt. The higher over a watt the cooler they are when you touch them. That's all.

Coppertop412; Yes you're overlooking something. Look at post #101 in this thread. You are not measuring the currents correctly as far as I can tell.

Please set you meter to VOLTS and plug the leads into the appropriate holes to get you VOLTS and measure the VOLTS across your 1 ohm resistors for the two strings.

Tell us what you get.

[Cipher43]

Let me start off by saying i love the build you have done. Im getting ready in the next month to build an LED fixture for a 120 (4'X2'X2'). I think you may have talked me out of a premade heatsink as well. What size exactly is this tank you have cause im not good with converting the dimentions. Cant wait to see a pic of them in action. Also are you planning on getting some par readings off of your tank cause I think that would help "the LED cause". Also would like to know how hot your LEDs and heatsinks are with the fans off.
Thanks for posting this build

[kcress]

Cipher; It's not, "fans on fans off", it's more about the air temp around your aluminum. Is it open and free to exchange the room air around it? Or is it closed up in box? That will control the ambient around the fixture. That's the most important thing.

[jpccusa]

Let me start off by saying i love the build you have done. Im getting ready in the next month to build an LED fixture for a 120 (4'X2'X2'). I think you may have talked me out of a premade heatsink as well. What size exactly is this tank you have cause im not good with converting the dimentions. Cant wait to see a pic of them in action. Also are you planning on getting some par readings off of your tank cause I think that would help "the LED cause". Also would like to know how hot your LEDs and heatsinks are with the fans off.
Thanks for posting this build

The dimensions of the tank is on post #1. It is roughly 100 US gallons.

I tried taking pictures yesterday but the result is really far from the real thing. I am planning on posting a video instead, so at least people can have an idea of how much shimmering you get. It is almost too much! :D

I don't have a par meter but I am willing to let people take measurements of my tank if they want to. Just PM me and we can schedule something.

As for color, without changing the wall wart pots, I find the color to be too blue. I am glad to have the ability to change the color with the turn of a knob - something I was never able to do before. That alone makes this entire project SO WORTH IT! (not to mention the excessive shimmering).

The aluminum bars are roughly 1 inch away from the top of the canopy, as shown on previous pictures. The canopy is closed all around, including the back. Without the fans on, the bars do get lukewarm. With the two fans on, I can barely tell the warm up.

Thanks for the nice words. I will try posting the video link soon.

[jpccusa]

I forgot to say that after I finish installing the LEDs, the whites are pretty much the same current, but the blues have a difference of about 50 mA (617 v. 667). Do I need to do another switch or should I wait and see how they will be in a while (weeks, months)?


Here is the promised video.
<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/X-mwtQePcVI?hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/X-mwtQePcVI?hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>

* I had a problem with hairy algae due to an almost complete water change a few months ago (broken glass heater which annihilated my tank) and bad lighting.
* The spiny thing on the right is a fake glow in the dark decoration.
* You can see in the video how deep the light penetrates the sand (about 1 inch).

[Coppertop412]

OK here's what I get: .001 on the dim string and .021 on the brighter one with the dimmer pot almost all the way down (barely on). Dimmer at max (still leaving internal adjustment alone) .043 on the dim string and .337 on the brighter one.
Where do I go from here?
Thanks so much for your expertise!

[jpccusa]

I think the next step for you would be to measure each LED and create a table like the one on post #69.

That will give you an idea of your high and low Vfs.

Once you have that, you can start switching LED's from strings (lowest from one and highest from the other).

[Cipher43]

To Kcress: Right now i dont have the stand built but am planning on making a canopy for it with 4 or so vents cut into the top and back so i dont know if i would need the fans but may put some on just for safety.

To JP: Love the video you posted...... Man thats A LOT of shimmer. This thread has made me feel better about doing an LED build because the Emperor has not clothing thread kinda had me scared.

On that note are you happy with the way the colors came out or would you change the number of blues or whites if you had to do it over again.

[Coppertop412]

OK, I figured out the 'little thing' I failed to to, it was back in first grade, when everyone else was learning to count! lol I relized I had 11 on one string and 12 on the other! Only took me 2 days to figure that one out. So now, with TWO strings of 12 I get .183 on the 'dim' string (still the same string) and .195 on the 'brighter' one. So now let me re-ask: do I need to check voltage and try to balance them better, or is .012 close enough?
And thank you for helping me figure out that I'm retar... sorry, mentally challenged. LOL

[Coppertop412]

One last question, what do you install the optics with. I was thinking super glue, but I read somewhere (I think on here) that it can ruin (i.g. cloud) the LED. If I put 2 tiny dabs on either side of the optic, with it in place, I should be fine, right?
Thanks again for you help and I have to agree on the great pics!

[jpccusa]

To JP: Love the video you posted...... Man thats A LOT of shimmer. This thread has made me feel better about doing an LED build because the Emperor has not clothing thread kinda had me scared.

On that note are you happy with the way the colors came out or would you change the number of blues or whites if you had to do it over again.

Thank you! The Emperor has no clothing was a great thread to learn about color aesthetics. Like I said many times, I like the shallow water type of look (less blue), hence me adding 2 of the warm whites.

If I had to do it again, I probably wouldn't do 50% whites, 50% blues. I would probably do 60% whites, and probably would add more neutral, possibly warm whites. This is not to say I am unhappy with what I got. I am extremely happy with the color and everything. The only reason I would do it differently would be so I could dim the blues less (I would have more LEDs working at full capacity). In the other hand, less blue LEDs would mean they have to be further apart from each other, which in turn could lead to spotting/colors not blending well. Just something else to consider. Another one of those trial and error things, I guess.

I hope the video I posted showed a variety of different colors, from hairy green algae, to green chromis, to Kole Tang. The video colors are a little more blue than the real thing. I can tell because the Kole tang appears to be somewhat purplish on the video, when in real life, it is more of a maroon/burgundy color. Other than that, it is pretty close to the real thing.

OK, I figured out the 'little thing' I failed to to, it was back in first grade, when everyone else was learning to count! lol I relized I had 11 on one string and 12 on the other! Only took me 2 days to figure that one out. So now, with TWO strings of 12 I get .183 on the 'dim' string (still the same string) and .195 on the 'brighter' one. So now let me re-ask: do I need to check voltage and try to balance them better, or is .012 close enough?
And thank you for helping me figure out that I'm retar... sorry, mentally challenged. LOL

I'm glad you caught the mistake. Now keep the multimeter across the resistor of the highest string, then slowly increase the driver's pot until you read .650 (that's where I chose to keep mine).

At a higher current, the difference between the strings will be bigger. If the difference is bigger than .050, you have to switch LEDs from their strings.

NOTE: 0.050 is a number I read before, but as you could see on a previous post of mine, I am unsure of that number. The correct balancing may require both strings to be within 0.030 from each other. Let's wait and see what the electronics guru say about this.

As for optics, I am not using any (not worried about par, my LEDs are really close to the water, etc.). I also read somewhere that the fumes of super glue will damage the LED. I would stay away from super glue if I were using optics.

[TheFishMan65]

I think that people finally decided a small amount of epoxy is the way to do lenses.

The difference kind of depends. The lower voltage/higher current string will get warmer and start to need less voltage and more current so it can get hotter and allow more current becuase of lowered Vf at the current so it can get hotter and hog more current so it ... do you need me to keep going? I would think a difference of 0.5 volts would be good, but check them every hour (or more often) and make sure it is staying there and there is not thermal run away. I would also check monthly just to make sure the LEDs age the same. The fuses are the last resort, but if they go the inhabitants are with out light until you get it fixed. Ideally you can see the problem coming and adjust the fixture at "night".

[kcress]

To all. I wouldn't worry about 50mA difference between strings. Over 50mA I'd start considering a swap.

0.050V measured across a 1.0 ohm resistor is showing you that 50mA is flowing thru the resistor. Since it's in series with the LEDs the same exact current is flowing thru them.

jpccusa; I suggest you swap out 4 to 8 of your blue LEDs for either CW or WW LEDs. It won't be any problem to have a few in your blue strings. The blue POT will still make a large blue difference. Just make sure that you swap the same types into the two parallel strings.

You'll find something to do with those blues you pull out.

[kcress]

I would always design for fans. You may find you need none or only one very quiet one will make a large difference by preventing the ambient temperature from building up in your fixture.

[jpccusa]

Kcress, by switching a few blues and whites, wouldn't I end up with a bluer tank? In other words, by mixing blues and whites in the same string, would I be losing the ability to adjust the colors separately?

I have 2 whites left over. IDK if it would make a difference to add those to the blue strings.

[kcress]

Why would you end up with a blue-er tank if you switched out blue LEDs and put in white ones instead??

Thinkaboutit. If it's too blue and you're turning down the blue ones to get the color you want then you can swap out blues until you don't need to turn it down at all and have the color you want. Likewise if you switch out a some blues you will still have "blue adjustment", just less and less. Ultimately you'd not want any adjustment at all. Any adjustment means you're throwing away some blue photons.

Ideally having blue and white adjust-ability is just to tweak it to perfection - not make massive changes. Large changes mean you missed your color goals badly.

[jpccusa]

I understand now. I thought you were talking about swapping whites and blues from their strings. What you meant was to actually buy more whites and replace some of the blues with them.

That is something I am considering for the exact same reason you mentioned (losing blue photons).

[UnusualSuspect]

JP - I'm following this thread with interest. My "Super-Duper-Ultra-Premium-24-LED-with-Dimmable-Drivers-DIY-Kit" should show up today or tomorrow, and I don't have any electronics experience. Lots of good info in this thread, and very well illustrated. Props to you and to all who have contributed.

I watched your video - that's about the amount of shimmer I'd expect based on my experience with my current "store-bought" Marineland Reef Capable LED fixture.

I'm actually fairly happy with the Marineland fixture, but it's too white. I'm supplementing it with a couple of blue Stunner strips. Like you, I want to be able to customize the color with the turn of a knob.

When I've completed my build, the Marineland fixture & Stunner strips will replace the compact flourescents on my QT/hospital/grow-out tank.

Thanks again for a real informative thread!

[chris023]

Wondering how to test continuity for the first and last LED in a string when using neighboring LEDs to test (who are the neighbors)?

"using your 'diode test' setting to light each diode from the neighboring LEDs successfully"

Thanks.

[jpccusa]

Indeed they don't have neighbors... I measured by placing the probes on the exposed cable BEFORE the solder for the 1st LED and AFTER the solder for the last LED.

[TheFishMan65]

Fuse/resistor/connection to the driver what after comes before/after the first/last LED

[chris023]

Just so I am crystal clear with my meter... The "diode" test would be done using the ~5:30 setting (->+), and the "short" test would be done using the ~8:30 setting (2000k ohm symbol). Sound right? Thanks.

http://i977.photobucket.com/albums/ae255/cpschuetze/Aquarium/LED%20Build/018.jpg[/QUOTE]

[TheFishMan65]

Diode yes
Short test no - use the 200 ohm setting

[chris023]

6:00 position... got it... thanks.

Diode yes
Short test no - use the 200 ohm setting

[KDHL]

jpccusa - excellent DIY project. Very detailed pictures. Wish all products' instructions are detailed like this.

[jpccusa]

jpccusa - excellent DIY project. Very detailed pictures. Wish all products' instructions are detailed like this.

Thank you! I wanted to create a detailed DIY thread exactly because I wish products instructions were this detailed as well.

I am a visual person, so when I read "put the positive wire into the second to last input, then the negative wire into the ground cable exiting from the middle part of the driver, then the ..." I have no idea what I am supposed to do.

Besides, a picture is worth 1000 words. :)

[shikhyung]

How far the led to the water surface?
do you use flexy shield, or glass for guard?
Thx.

[kirsto71]

Great build. Just one thing I couldn't work out is how do you determine the resistor and fuse sizing. I assume the fuse is to limit maximum current to the string.

Is there a reference link you have I could read.

[TheFishMan65]

Yes, the fuse limit the maximum current.

The resistor just makes it easier to measure the current. rather than turning off the fixture, breaking a string, adding meter, turning on, measuring the current, and the repeat in reverse to remove the meter (and then repeat for each string). you can just measure the voltage drop across the resistor,

Since Voltage = Current * Resistance a 1 ohm resistor means a 1 volt measured across the resistor means 1 amp is flowing through it.

[ezlight]

PRICE LIST

* 50 LEDs + 8 fuses + 8 resistors + 8 terminal blocks + 2 drivers + 1 wall wart + 2 pots = $275.90 shipped (Group buy)
* Multimeter = $20 shipped (Ebay)
* Thermal Compound = less than $10 shipped (can't find the receipt)
* 2 Computer Fans + 12v wall wart = $15 (Ebay + Fry's)
* 18 ft. Aluminum Channel = $20.55 (Industrial Metal Supply Co.)
* 90 ft. #22 wire (3 colors) + Soldering Iron + Solder + Desoldering Braid = ~$25.00 (RadioShack)
* Hardware = ~$20.00 (HomeDepot)

Total Cost = ~$386.50 spent along ~ 6 months (my first purchase was the multimeter back in October of 2010)

Now please tell me, what the heck is the difference between what you've done, and the other threads that say they have $1500+ into their builds?

Mind you, I'm completely the DIY type of guy when it comes to saving a boatload of $$$. It makes me do the happy :dance:

[TheFishMan65]

IMO the $1500 guys are probably doing closer to 200 LEDs and they bought the massive heat sinks and did not search for the best LED price.

[Mikey912]

they probably also didn't run their strings in parallel like JP and spent more money on the drivers as well.

Nice Build and guide JP! I'll be using this as my guide once my fuses and resistors that i ordered come in. (used the link Kcress Provided :thumbsup: )

[packman90]

this is a great thread, I am attempting to build my on LED setup and have had some issues with it, but know after reading such good directions I feel confident I will solve my problems.

[jpccusa]

How far the led to the water surface?
do you use flexy shield, or glass for guard?
Thx.

The LEDs are about 5 inches from the water surface (I can measure it and tell you exactly what it is).
My tank is acrylic, with cover, therefore I didn't use a splash shield directly on the LEDs.

<a href="https://picasaweb.google.com/lh/photo/Dh__IpWdXOj-zBSji_XnfPJgFuh2q-qcJYa90J5SMhc?feat=embedwebsite"><img src="https://lh6.googleusercontent.com/_ytQbgTx0aag/TbpM3Xb6zxI/AAAAAAAAHNs/9A1LYOts7-4/s800/IMG_4690.JPG" height="600" width="800" /></a>
Detail of my tank's cover and LEDs

Regarding the high price, I believe FishMan and Mikey got it... Also, group buys allow for great deals.

For those finding this thread helpful and encouraging, I'm glad! This is my way of helping others the same Kcress, TheFishMan65, Katchupoy, and many others (people and threads) have helped me. So, feel free to post your questions or concerns pertaining to DIY LEDs wired in parallel on this thread. Hopefully someone will quickly get back to you.

[KDHL]

...so when I read "put the positive wire into the second to last input, then the negative wire into the ground cable exiting from the middle part of the driver, then the ..." I have no idea what I am supposed to do.

Besides, a picture is worth 1000 words. :)+1 on this statement. Diagrams and pictures are worth 1000000 words. :bounce3::bounce3:

[ezlight]

For those finding this thread helpful and encouraging, I'm glad! This is my way of helping others the same Kcress, TheFishMan65, Katchupoy, and many others (people and threads) have helped me. So, feel free to post your questions or concerns pertaining to DIY LEDs wired in parallel on this thread. Hopefully someone will quickly get back to you.

Well, I'm in process of a 180 build now. My next task is to get my sump design figured out, plumb it all upon my next shipment, put rock & water in it to get the cycle started. Then I'll be working on hood design, & lighting.

How did you figure out your spacing of the LED's? Was is just even spacing due to the amount of LED's you bought, or heat/other limits that I'm not aware of? I don't want to go crowding LED's if there are other considerations.

Have you been able to do a PAR reading yet? Just curious how effective it is.

With your build, how would it be possible to automate the lighting? (turn on, switch gears, increase lighting intensity, ect. ect.?) I've seen others mention that at different times they turn em on, then increase %.

The cost effectiveness of your build has me gung ho about the project, but then other threads have me gun shy! LOL

[TheFishMan65]

With the write driver they can be dimmed with a Arduino type controller. Most drivers support this, but not all.

Spacing is usually pretty even distribution, but the row and column distance may not be the same. Normal distances IMO range from 2-4 inches. Spread them out to cover the tank and the number depends on what you want to keep.

[jpccusa]

The spacing is determined also by what you plan to keep in your tank. Hard corals require more light, while fish-only can be kept at lower light intensity. FishMan's thread Summaries has those numbers for you.

No par reading. I didn't get any PM from people wanting to measure it.

[Algaenot]

Based on what I’ve learned on these threads I now see several flaws in my build including using large heatsinks which are overkill for my application, using too many Mean Well ELNs running in series, miscalculating the number of LEDs per driver, and using epoxy to attach the LEDs to the heatsink.

Regarding the number of LEDs to run per each mean well ELN-60-48, I’ve encountered several different recommendations on the threads in Reef Central and several others. I had originally designed the system using 14 cree XP-Gs and XP-Es per driver but realized later that 12 allowed a reasonable amount of “buffer”. At least I figured this out before I began construction.

If I had a mulligan on my build, I would design it in a more linear fashion as in this thread and use the Mean Well HLG series of drivers. I would also mix in more neutral white LEDs.

There is a great deal of information on DIY LEDs on RC and it’s well worth spending the time to read through everything that’s available. Several individuals have invested a great deal of time answering questions and keeping a few of us alive and they deserve our thanks. Kcress, The fishman65, katchupoy, der willw zur macht, soundwave, and several others – thanks for being patient with us.

[kcress]

Thanks Algaenot! We appreciate the appreciation. :thumbsup:

[Cipher43]

With the write driver they can be dimmed with a Arduino type controller. Most drivers support this, but not all.

Spacing is usually pretty even distribution, but the row and column distance may not be the same. Normal distances IMO range from 2-4 inches. Spread them out to cover the tank and the number depends on what you want to keep.

So if you use the arduino can you use the ELN 60-48D or is it the ELN 60-48P

[mauger1]

Looks great! I just got done with my led build

[TheFishMan65]

IMO the P works better with the Arduino - just need a transistor.

[roundman]

I would also like to thank all who helped with this thread and all of the other LED threads.
I have some stuff already and some is in the mail. I got the ELN P drivers so some of the arduino is still confusing for me but will figure it out I hope.

[TheShadow]

Would these fuses work for this application
Fast-Acting 1A, 250V Glass Fuses
they seem to be easier to get locally

[Cipher43]

IMO the P works better with the Arduino - just need a transistor.

is it possible with out hurting the LEDs or the drivers with the D cause im not sure if or when i will do the arduino so if i can adjust the lights manually till then it would be nice.

[TheFishMan65]

Would these fuses work for this application
Fast-Acting 1A, 250V Glass Fuses
they seem to be easier to get locally

Those should work.

[TheFishMan65]

As far as I have read you can PWM the D without damage (at least in a years time I would guess). The problem is the D is not linear with respect to the PWM percentage, but the correction is posted somewhere.

[jeffreylam1132]

Subscribe!

[lordofthereef]

Yes, a square tube is far worst for cooling than U-Channel. Probably less than half as effective.

Suggestions:
Use these terminal blocks if you want 2-position:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=A98503-ND

or use these if you want 6 positions:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=A98507-ND

Use these resistors:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=UB5C-1.0-ND

Use these fuses:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=F2313-ND

Probably a stupid question, but is all of this available locally at something like a radio shack?

[kcress]

Subscribe!


Rosemead? I thought.. Well. You know. Didn't Andromeda Strain takeout everyone there?

[kcress]

Probably a stupid question, but is all of this available locally at something like a radio shack?

I don't think so.. But your local electrical supply place might have them. The place where all the electricians get their materials.

[lordofthereef]

I don't think so.. But your local electrical supply place might have them. The place where all the electricians get their materials.

Thanks. Will have to do some research then.

I know it's been said many times, but thanks for all the input forum-wide. You guys make it so we have to ask very few questions!

[jpccusa]

I just wanted to report that I swapped 4 of my royal blues.

Not only both strings are now within 40 mA of each other, I now have to dim the external pot very little to get the color I like. :dance:

The numbers of LEDs, in the end, are: 18 XP-E Royal Blue (burnt 2, swapped 4) + 18 XP-G Cool White (swapped 4) + 8 XP-G Neutral White + 2 XP-G Warm White

CAUTION: I burnt a second RB tonight, and I am not sure why. My suspicion is that I left the the driver and wall wart plugged in, even though the timer which control them was on the off position. While I was soldering, I noticed the LED being soldered dimly turn on. When I did the continuity check and the short check, one unrelated RB didn't turn on. Just to be safe, UNPLUG EVERYTHING. Don't trust on/off buttons.

[BluScrnOdeth]

with those POTs that you have, are you able to set how far you can turn them? Just to help prevent from burning it if you try to turn the led's down too much. What kind of POT is it also, i didnt notice you mention what kind you got, but i did notice it said something like 10k on it???

[jpccusa]

with those POTs that you have, are you able to set how far you can turn them? Just to help prevent from burning it if you try to turn the led's down too much. What kind of POT is it also, i didnt notice you mention what kind you got, but i did notice it said something like 10k on it???

I haven't tried to set how far I can turn the external potentiometers because I was not aware there was a risk of burning them by turning the LED's down too much. What I have experienced is that at a minimum, the LED's turn off.

I will let TheFishMan65 answer what kind of pot they are. I have no idea.

[TheFishMan65]

The pots are hooked to a Meanwell I believe. Just a regular 10k. BSOD you are looking for a much higher wattage and lower resistance IIRC.

[vietcu]

Alright guys I am in need of a little help with my setup again. I took a week or so hiatus to do other things. Tonight I hooked up my Led following the directions exactly and out of the 26 Led, the last four came on. Disregard the string with white wires, that is totally a different string. The strings I am working on right now are the ones with Orange and Red wires. The Leds circled are the ones that came on.
http://i298.photobucket.com/albums/mm262/vietcu/IMG_1719-1.jpg

1. 1 meanwell 48D, hooked to 2 lines of 13 Xpgs. Red+ wire from the Meanwell wen to one block of which I jupmed it to connect 2 Resistors. The resistors went to another block which was connected to two Fuse. From the fuse went to a third block which was then jumped together to the Black - wire of the meanwell.
http://i298.photobucket.com/albums/mm262/vietcu/IMG_1716.jpg
http://i298.photobucket.com/albums/mm262/vietcu/IMG_1717.jpg

2. I had the pots connected so that the two wires from the 10v went to the left and right connectors. Had the Blue wire from the meanwell connect to the middle connector, and the White wire went to the far right connector of the pot.
http://i298.photobucket.com/albums/mm262/vietcu/IMG_1718.jpg

3. After the no fire of the LED, I went back and check each LED using the voltmeter to make sure that each LED still came on.

So what do I need to test at this point? I am almost certain I wired everything up correctly, is it because I have 2 more LED on the strings than I am suppose to? Just to point out the LED string would fire up just fine if I hooked up the meanwell to each string individually.

[kcress]

vietcu you need to go back to post #62 and understand it and the following pictures in the next 15 posts.

[ronald7410]

Question, What do the Pots do? are they necessary for parallel setup?

[ronald7410]

Ok disregard my previous question. I have non-dimmable drivers, I use pots to make them dimmable?

[Gold Stripe]

Ok disregard my previous question. I have non-dimmable drivers, I use pots to make them dimmable?

No. You use pots to dim dimmable drivers. Non-dimmable drivers are non-dimmable.

[gmigmi]

great great thread.
THANKS

[billyzbear]

Great thread. I have read else where that you can run 14 LEDs on these drivers. Can you run 2 x 14 stripes in parallel series? 12 across 5 ft doesn't seem enough for a 6 ft tank.

[imagex]

i've ran 15 xp-g across but they have a lower forward voltage then the xr-e... but yea 14 is very possible.. but i've ran these in parallel without the resistor and jumper sucessfully without problems for 2 years.. is the resistor and fuse to up the eln series to run a max of 1a each string?? also why is everyone using screws to mount thats main reason for all your guys shorts.. just use thermal epoxy and be done with it.. it's actually cheaper then using screws and thermal epoxy..

[Gold Stripe]

Remember that the more voltage you try to draw, the less current you will have available. I believe JP ran 2 strings of 11 and could push them near 1000mA each but if you run strings of 14 then you probably wont be able to drive more than 650mA or so and you will be running near 100% capacity which may generate more heat and shorten the life of the driver. Best to leave a little breathing room.

[billyzbear]

I'm planning on XP-E royal blue. JP used 12, I believe.

[Gold Stripe]

Datasheet for RB shows FV at 3.2 running 350mA and 3.5 running 1000mA. At 700mA you may be near 3.4 which would be 47.6V total. Just under the driver max rated capacity. If they peaked at 3.5 then you would be at 49V total. Exceeding driver max rated capacity. Not much room for error, especially running 2 strings.

[TheFishMan65]

The ELN can be turned up to 52.8 volts. It won't be able to run to parallel strings at that voltage, but one should work. Now if you also push the current to the max (1.3 amps) you may stress the ELN and have an early failure.

[billyzbear]

I work on cars for a living. I understand some of this but not much. So, I shouldn't use 14 but 12 would be ok?

[kcress]

Yes. 12 is guaranteed to work, 14 might work...

[jbannick18]

Great thread, glad I came upon it. I have a 75 gallon I was thinking about putting led's on but I wasn't sure if 48 would be enough coverage but your video says otherwise :D

[billyzbear]

I have no exp. with leds. Do you think having the leds spaced 4" apart with no optics is going to be ok? I don't want it looking like spot lights.

[TheFishMan65]

If oyu raise them high enough you will not have spot lighting, but you may also not have enough light for what you want to keep.

[billyzbear]

I forgot, they'll be around 6-7" off of water.

[TheFishMan65]

I think that will be to close. Katchupoy just posted a picture (http://www.reefcentral.com/forums/showthread.php?p=18870403#post18870403)that will let you see what is going on.

[SC Reefaholic]

Kress, if you're out there, which of these would I want to use on my 2 x strings of 11 XP-G driven by HLG-100H-42B (42V at 2.23A)

Digi-Key
025501.5M-ND
025501.5NRT1-ND
025501.5NRT2-ND
025501.5NRT3-ND

The strings should max out at 1120mA and the XP-Gs are supposed to handle 1500mA so I figured a 1.5A fast blow would be ok for these strings.

Thanks!

[ovrboost]

this is the best thread i have read about diy'ing leds. It is very informational and detailed.

[kcress]

Kress, if you're out there, which of these would I want to use on my 2 x strings of 11 XP-G driven by HLG-100H-42B (42V at 2.23A)

Digi-Key
025501.5M-ND
025501.5NRT1-ND
025501.5NRT2-ND
025501.5NRT3-ND

The strings should max out at 1120mA and the XP-Gs are supposed to handle 1500mA so I figured a 1.5A fast blow would be ok for these strings.

Thanks!


I'd prefer using something closer like 1.3A but they appear far and few between.

Your references aren't working for me. I doubt you need 5000 of them. :strange:

Use this one or a similar one:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=F2319-ND

At over an amp you might want to use 0.1ohm resistors instead of 1ohm ones. Just remember to move the decimal point when checking the current by measuring the voltage across them.

I suggest this resistor: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=0.1ACCT-ND

[SC Reefaholic]

Thanks! Just placed the order.

[SC Reefaholic]

This is going to be a really dumb question but...... on the ELN-60-48D, the brown wire (ACL) is positive and the blue wire (ACN) is negative and there is no ground right?

[kcress]

Correct terminology is "ACLine" and "ACNeutral". No ground it seems.

[SC Reefaholic]

Thanks!

[streak]

I just wanna say you have a great build and with laymans terms that i can even understand but when i decide to get stuff for my 75g I was wondering and have been reading alot about led builds. I would like to know how many leds you would need for a 75 I have read that monster led thread already but he didnt use optics. I would like to so i can grow any type of coral. Also i was looking for bluish 20k look. My problem is comming up with the amount of Led's I was thinking around 96? with 2:1 ratio. Any help or link would be appreciated.

Oh and how many drivers would i need to pull this off. I have looked at the various ledsupply reefleds but they just have prepackage stuff no real info.. That i could understand.

[TheFishMan65]

I have 48 over a 75 I don't think you would need more than 72. Depends on how you wire it with 4 ELN or 2 HLG would probably be best.

[patmack]

JP, You do have a great build thread. I had to refer back to this when I was balancing my strings. Thanks!

[SC Reefaholic]

Look at the Thomas Research drivers. They have a pretty good variety of dimmable drivers. I couldnt work out a setup using MeanWells because of the number of LEDs I am going to have on each string but I found the exact thing I was looking for with Thomas Research. Plan on ordering them in the next 2 weeks.

Edit that. There are some Meanwell HLGs that compare but still trying to get some feedback on their operation as far as ramping and how smooth/far they go.

[patmack]

Ill let ya know how my HLG 185-B's work later this weekend.

[Cipher43]

so JP any updates on how your tank is doing with the LEDs now and how the light is doing for heat?

[Chalu]

I'm getting ready to redo my ligt fixture and will be referring to this thread a lot. I plan to have parallel strings for the XRE CW/RB (because I already have them), each string per driver will have all like diodes - only whites or only blues; will these resistors and fuses still work?

There will be other strings also which will be regular series strings of XPE blue and XML NW. I may add UV and/or RGB diodes later or just supplement with T5's to "complete" the spectrum

Yes, a square tube is far worst for cooling than U-Channel. Probably less than half as effective.

Suggestions:
Use these resistors:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=UB5C-1.0-ND

Use these fuses:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=F2313-ND

[Chalu]

Cannot edit my previous post - must mention I will be using the meanwell 60-48P drivers

[TheFishMan65]

As long as each string on each driver has the same proportion of LEDS you shoul.d be ok. You can not easily do a string of white and a string of blues. Two string each half white and half blue work.

[S2minute]

Ah, most excellent!

Two things to do.

Do exactly what you are showing EXCEPT do not use the pads for the LED you're checking. Probe the other ends of the two wires that come to LED you are testing.

You have to do this so you test the actual solder joints on the LED of interest.

Do this test on every single LED. Bang bang bang bang. On a big build it might take 3 measly minutes.

That took another 3 minutes. It takes a lot less time than it took me to type this.. :hmm3:

As you rocket down all the chains make sure the polarity is what you expect. It has to be the same all the way down the string. You should see the pattern right away and be able to just hop from LED to LED.

That was the continuity test.

The other test is a shorted wire test.
This time probe a LED exactly as you show in your first two probe pictures. Exactly.

Once you see the LED light up you leave one probe on the pad. You move the other probe off the pad and onto one of the screws - only one - you don't need to do both. (This is to make sure you're touching the aluminum because sometimes it's anodized and hence insulated but screws always cut thru that.)

If with a probe on the screw/heatsink the LED lights the solder joint, wire, or a screw is shorting out LED drive current to the heatsink.

Because there are two LEDs and two solder connections on each wire the short could be on the neighboring LED or the LED you're testing.

If when you moved the one probe to the screw the LED correctly did NOT light up, return the probe to the LED pad and confirm the LED lights up. THEN move the other probe off the pad and onto a screw. This tests the other side for a short to the heatsink.

Ok, so i'm soldering the wires and while applying the iron/pushing the wire into the mound of solder , i notice the LED is very dimly lighting. First time i noticed, that so i checked doing a shorted wire test. Sure enough, probe to screw and the led lit. Then i noticed the other solder joint was crappy so i resoldered and it worked fine. Why would a bad solder joint cause that? Is it that the wire itself has to be totally incased by the solder?

[wlatino30]

led bump

[TheFishMan65]

S2 was anything else plugged in? Was the heat sink grounded in some way?

My guess is that the soldering iron has some short (maybe normal) that is letting some current through. Something was grounded so the LED lit.

[ezlight]

Why the 3 different white lights?

[TheFishMan65]

ez,
Not sure what 3 you are referring to. There are cool white that are blue compared to neutral (a little yellow) or warm which appear redder when the thre are compared.

[S2minute]

S2 was anything else plugged in? Was the heat sink grounded in some way?

My guess is that the soldering iron has some short (maybe normal) that is letting some current through. Something was grounded so the LED lit.

As far as i know, nothing else was plugged in. I'll check the irons cord now.

[Cipher43]

Any updates JP?

[ezlight]

Color: 24 XP-E Royal Blue + 16 XP-G Cool White + 8 XP-G Neutral White + 2 XP-G Warm White


ez,
Not sure what 3 you are referring to. There are cool white that are blue compared to neutral (a little yellow) or warm which appear redder when the they're compared.

I was just curious why JP picked 3 different whites, and how he came up with that ratio.

[Cipher43]

I was just curious why JP picked 3 different whites, and how he came up with that ratio.

A lot of people it seems are going with more than just royal blue and cool white anymore for a few reasons. The main ones being those other color whites give you more of the light spectrum that may help the stuff in your tank grow. The reason most people only throw a few in there is that the cool white give a super crisp white look to the tank while the neutral whites give a slight yellowing and the warm whites are very yellow so you only want a few to reduce the yellowing.
I know on my LED build I plan on using 2:1.5 or so cool whites:neutral whites and about the same ratio of royal blue:blue. Its a lot to do with your preference on tank appearance

[kcress]

It's not for growth it's to allow things in the tank that are red to be more visible. The feeling is, all CWs and RBs and a tank often looks washed out. So some of added NW which are definitely redder than CWs. Of course if a little more red is good a whole bunch more must be better so some have gone with WWs which are reeeeallly red and need to be used sparingly.

It seem to my personal taste that NW are plenty red enough. I'd go with anything in the 3CW to 1NW up to 1CW to 1NW depending on how much of a blue freak you are/aren't.

Also Blues are pretty overwhelming and should be used sparingly whereas RBs don't tend to be. I know several people who've had to yank out a bunch of blues because they just ran rip-shod across the tank's color.

[SC Reefaholic]

This may sound like a dumb question but how do you measure individual Vf without blinding yourself?

[kcress]

Get over at an angle and wear dark glasses. Squint.

It is a bit tough.

[TheFishMan65]

Hold the probes on the LED and with your third hand power up the system :)

Lenses can also help since they will direct the light up and cast a shadow.

[jpccusa]

Glad to see this thread still being used. This was a really fun project and definitely a great learning experience.

Updates? Not many. Everything looks great with the LEDs. I am still impressed with the amount of shimmer, and still very happy with the tank's color. I got a very cool and simple automatic dimmer from a friend, so now I have simulated daylight (sunrise, noon, sunset). That is a cool feature because it creates different hues throughout the day, instead of having one color from "on" until "off". I also added acrylic splash-guard to the array since I came really close to touching the LEDs/wires with my wet elbows a couple of times while cleaning the tank. The cooling fans are still working quietly and well.

A special shout out to my mentors on this thread: Kcress, TheFishMan65, Katchupoy, etc. :wave:

[S2minute]

It's not gonna be that easy JP :spin3: We wants to see pics!!! :beachbum:

Or better yet...a VID!!

[jpccusa]

Here (http://reefcentral.com/forums/showpost.php?p=18718922&postcount=117) is the video.

[S2minute]

VN JP :)....your right about the shimmer. I like it!.

[Pierre3512]

I'm building a 54 led fixture for my 75g. It consist of 9CW 9NW and 36 RB all Cree.

The CW NW and 12 of the RB are running on separate ELN 60-48P driver.

To save on driver I decided to do 2 parallell string of 12 RB but I have a problem trying to balance those 2 string also on ELN 60-78P.

Sting 1= 449mv 3.050 3.050 2.97 3.03 3.263 3.340 3.193 3.178 3.192 3.339 3.759 3.168

String 2= 600mv 3.071 3.253 3.050 3.250 3.216 3.236 3.089 3.247 3.033 3.039 3.420 3.355

based on my understanding I swap the 3.759 from string1 with the 3.033 of string2

String 1 went to 573mv and string 2 474mv now string 1 was the highest one???

So I the swapt the 2.97 from string1 with the 3.420 of string2 resulting in string 1 now at 450mv and string2 at 600mv.

I'm back to square one and quite a bit confuse as to what to do next.

Help would be really appreciated

[kcress]

Interesting. You have the idea down correctly. I'd not bother with second and third decimal places as they're not important and will reduce your hassle. Stick with '3.1' etc.

That 3.8 (rounded) is the problem child. Any chance you have an extra one so you can just swap that one out altogether? If not just leave it in one place as un-swappable and proceed with balancing like it's not there.

[Pierre3512]

Tks kcress I will ignore the 3.8 and see what happens.

I'll let you know

[TropTrea]

The big thing to remember is these are all interdependent. when you decrease 1 the others will slightly increase. or whan your increase one the others will slighly decrease.



I'm building a 54 led fixture for my 75g. It consist of 9CW 9NW and 36 RB all Cree.

The CW NW and 12 of the RB are running on separate ELN 60-48P driver.

To save on driver I decided to do 2 parallell string of 12 RB but I have a problem trying to balance those 2 string also on ELN 60-78P.

Sting 1= 449mv 3.050 3.050 2.97 3.03 3.263 3.340 3.193 3.178 3.192 3.339 3.759 3.168

String 2= 600mv 3.071 3.253 3.050 3.250 3.216 3.236 3.089 3.247 3.033 3.039 3.420 3.355

based on my understanding I swap the 3.759 from string1 with the 3.033 of string2

String 1 went to 573mv and string 2 474mv now string 1 was the highest one???

So I the swapt the 2.97 from string1 with the 3.420 of string2 resulting in string 1 now at 450mv and string2 at 600mv.

I'm back to square one and quite a bit confuse as to what to do next.

Help would be really appreciated

[Pierre3512]

kcress It work string 1 is now 504 and string 2 543. I think this is acceptable as per your instructions. Please confirm.

I'm also interested in your controler build is the info on your site the most current or is there a newer version with list of parts etc.

Thank you again

[kcress]

The big thing to remember is these are all interdependent. when you decrease 1 the others will slightly increase. or whan your increase one the others will slighly decrease.

Absolutely. The measurements for each LED change as soon as you change the current thru the strings. When you measure them all you're really after just the order of voltage drop. "This is the highest the is the next highest, this is the lowest, this is the next lowest." That's why all the decimal points are pointless...

[kcress]

Hi Pierre. Glad you got it. What you have going now is fine.

[TropTrea]

I have just read through this thread because I got realy confused on some of the numbers that were given fom various reads especialy the end ones where your trying to balance the strings of LED's. I have worked my whole life in electronics from simple to extremly complex projects yet I'm realy confused on the resister in this circuit and the values for them. If someone could simply put this in schematic form I'm sure it would make a lot more sense to me.

While I have not sorked with the new LED's I do have a few questions based off of some of the pictures I see here. Sheet metal screws were used to mount the LED's and some of those screws look dangerioult close to the pads where the solder connections are. Has anyone considered plastic screws for these instead of metal screws. I'm not sure how hot these LED's get but the basic effecenciey of a LED is based on converting a higher percentage of power light and lower percentage to heat therefore I would assume that heat is not a serious issue that would prevent the use of plastic screws.

My self I'm considering a simple moon light fixture initialy using 6 XP-C-D3 with a 24 volt power supply and a home built current regulator adjustable between 125ma and 400ma. However It appears the LED's in the photo's here would be a lot easier to mount. So that is it is a little debatable as to which Royal Blues I'd be choosing. If this project works out my next one will be providing light for one of 30 gallin breeder thanks that I'm using growing out frags.

Note I'm going to be running this on a 120 gallon tank and want it considerably brighter than a standard moon light since they will only be on about 4 hours every day with the first hour in conguction with my dusk lighting.

[kcress]

I have just read through this thread because I got realy confused on some of the numbers that were given fom various reads especialy the end ones where your trying to balance the strings of LED's. I have worked my whole life in electronics from simple to extremly complex projects yet I'm realy confused on the resister in this circuit and the values for them. If someone could simply put this in schematic form I'm sure it would make a lot more sense to me.
http://www.box.com/shared/static/a6kqebyng0.gif



While I have not sorked with the new LED's I do have a few questions based off of some of the pictures I see here. Sheet metal screws were used to mount the LED's and some of those screws look dangerioult close to the pads where the solder connections are. Has anyone considered plastic screws for these instead of metal screws. I'm not sure how hot these LED's get but the basic effecenciey of a LED is based on converting a higher percentage of power light and lower percentage to heat therefore I would assume that heat is not a serious issue that would prevent the use of plastic screws.

People use nylon screws. I wouldn't as I'd be worried about the nylon relaxing and having the LED's overheat. LEDs do get hot. The stars of course don't get as hot. Metal screws correctly chosen or used with plastic washers are both commonly used with no issues.

My self I'm considering a simple moon light fixture initialy using 6 XP-C-D3 with a 24 volt power supply and a home built current regulator adjustable between 125ma and 400ma. However It appears the LED's in the photo's here would be a lot easier to mount. So that is it is a little debatable as to which Royal Blues I'd be choosing. If this project works out my next one will be providing light for one of 30 gallin breeder thanks that I'm using growing out frags.

That would be pretty dang bright. Take a look at the "LEDs on a budget thread".

Note I'm going to be running this on a 120 gallon tank and want it considerably brighter than a standard moon light since they will only be on about 4 hours every day with the first hour in conguction with my dusk lighting.

Ah, that would work then.

[one clownfish]

I would like to say thank you to everyone for all the help and pictures, I NEVER would have tried to do something like this on my own without all this information, so again thanks. I bought a 12 led setup from rapid, trying to figure out what mixture of leds will work for me before I go big and put an all Led fixture over my 220gal DT.

[TropTrea]

Okay so this then makes a lot more sense seeing your circuit. The set valued resisters are there simply for reference points. Thanks for your schematic. Since I'm only going to be using a single chain I should not have to worry about the resistor since I won't be trying to balance two parralell legs.

On your note that my idea would be a bit bright as well as myself prefering your star LED's would there be a series of LED's you would recommend.

[TheFishMan65]

Consider using the resistors anyway. He allows you to monitor the current without turning off the circuit, opening the string (maybe unsoldering), inserting the meter, turning back on. Then repeating in reverse to get the meter out.

[kcress]

I agree with FishMan's assessment.

For moon lights I'd probably use either a handful of the little "gum drops" which are called "T1-3/4" or I'd use two or three royal blue Crees with a wall wart chosen to not provide enough voltage to light them much. It might be easier to add an adjustable resistor to dial them to where you want them. And again I suggest you look at the "LED budget build".
http://www.reefcentral.com/forums/showthread.php?t=1751598

[Pierre3512]

kress, I can't answer your pm I don't have enough post.

Do you have an alternative

[TropTrea]

I agree with FishMan's assessment.

For moon lights I'd probably use either a handful of the little "gum drops" which are called "T1-3/4" or I'd use two or three royal blue Crees with a wall wart chosen to not provide enough voltage to light them much. It might be easier to add an adjustable resistor to dial them to where you want them. And again I suggest you look at the "LED budget build".
http://www.reefcentral.com/forums/showthread.php?t=1751598

I was realy going to go with the high powered LED's for two reasons.

1. Give me some experience working with them before I try a big build for one of my frag grow out 30 gallon breeder tanks.

2. I realy want more than what standard moon lights give. I call them moon lights but in reality I'm looking for something to run only in the dusk time period, from when the mid day lights turn off, to about two hours after the dawn to dusk lights turn off. With my timming set up now the early morning hours are boasted with natural room light however I'm a late nighter so would like to continue seeing a little tank glow till my normal bed time around midnight.

My original thoughts were a Blue or Royal Blue LED that runs about 250 ma to 400 ma. On a 120 gallon tank running either 4 or 6 of them dependent upon how the light spreads evenly across the tank.

[Dirrk]

I have been following some of the diy led threads with interest as I am considering a build. I see all this open wiring,zinc screws in aluminum, etc., mounted over a saltwater tank as a potential (pun intended) corrosion problem. I know LED lighting is sorta new, so maybe this issue hasn't surfaced yet. Does everybody use a 100% glass or acrylic cover on the tank to help with this? If so, doesn't the cover reduce the efficiency of the lights? Every thing over my tank collects salt . I have decades of experience living on or near saltwater, and find corrosion to be a huge problem, and worse when you add a little electricity to the mix. I am truly impressed by all the technical expertise I see in these forums and by the time dedicated to helping others. so I look forward to hearing members thoughts on this element of LED diy design.

[TheFishMan65]

Most people with their lights under about 2 feet have covers. I have mine up about 2 feet with no problem.

[TropTrea]

I have been following some of the diy led threads with interest as I am considering a build. I see all this open wiring,zinc screws in aluminum, etc., mounted over a saltwater tank as a potential (pun intended) corrosion problem. I know LED lighting is sorta new, so maybe this issue hasn't surfaced yet. Does everybody use a 100% glass or acrylic cover on the tank to help with this? If so, doesn't the cover reduce the efficiency of the lights? Every thing over my tank collects salt . I have decades of experience living on or near saltwater, and find corrosion to be a huge problem, and worse when you add a little electricity to the mix. I am truly impressed by all the technical expertise I see in these forums and by the time dedicated to helping others. so I look forward to hearing members thoughts on this element of LED diy design.

Light is basicly light at a given frequency regardless if the source is LED's, Florescent Bulbs, Metal Hides or even Incadescent bulbs. Yes glass does have a filtering effect on light rays and the shorter the wave lenght is the more effect it has on them. Simularly the thicker the glass is the more effect it has on the light rays.

Glass is used as a basic filter for the prevention of UVC rays from being emitted. It does allow some UVB rays through and most of the UVA rays. Since we are talking about lighting for corals the shortest wavelengts we are working with are roughtly 380 nm. Glass slightly filters at this frequency however it not enough to cause any major concerns. With light in the 460 nm range the filtering of glass is almost unmeasurable.

Acrylic, thermoplastics also have some filtering effect however each different compound does have different filtering effects from the others. For equal thickness of these clear materials compared to glass the filtering effect is much lower provided the material is clear. Obviously frosted plastic or tinted plastics will have a considerably higher filtering ability than clear simular to glass.

[Dirrk]

Most people with their lights under about 2 feet have covers. I have mine up about 2 feet with no problem.

fish: at that height I assume you need tight 60? optics to keep the light IN the tank?

[TheFishMan65]

40s :)

[Dirrk]

Light is basicly light at a given frequency regardless if the source is LED's, Florescent Bulbs, Metal Hides or even Incadescent bulbs. Yes glass does have a filtering effect on light rays and the shorter the wave lenght is the more effect it has on them. Simularly the thicker the glass is the more effect it has on the light rays.

Glass is used as a basic filter for the prevention of UVC rays from being emitted. It does allow some UVB rays through and most of the UVA rays. Since we are talking about lighting for corals the shortest wavelengts we are working with are roughtly 380 nm. Glass slightly filters at this frequency however it not enough to cause any major concerns. With light in the 460 nm range the filtering of glass is almost unmeasurable.

Acrylic, thermoplastics also have some filtering effect however each different compound does have different filtering effects from the others. For equal thickness of these clear materials compared to glass the filtering effect is much lower provided the material is clear. Obviously frosted plastic or tinted plastics will have a considerably higher filtering ability than clear simular to glass.

thanks for the input on the effect of glass/acrylic covers.....makes me think I can use acrylic to fab a cover/ enclosure for the LEDs as long as I cool it.
I hope that combining a cover and a higher mounting level (12+ inches) I can avoid some of the potential corrosion issues I am concerned with.

thanks again for the quick reply. Looks like LED lighting is becoming more popular by the minute. I know my area electric rates are increasing rapidly.

[Dirrk]

40s.... wow I'll track down a pic of your setup. thanks.

[Dirrk]

Fish: I just discovered your summary of these monster led threads. perfect- YOU are THE MAN

[TheFishMan65]

There are some pictures in my album.
The summary is a little dated, but still has the basics.

[kcress]

Fish - YOU are THE MAN

Actually a small busy squirrel that hides tidbits in holes around his home(page).

[TheFishMan65]

He knows me so well.

[TropTrea]

There are some pictures in my album.
The summary is a little dated, but still has the basics.

Gee I remember years ago browsing through the photo albums here. But I thought they got rid of them. How do I find them now?

[Dirrk]

Fishman: I've been reading and following links. This stuff is evolving sssooo fast. I went to Cutter electronics, down under in Australia. they have jumped on the aquarium bandwagon with some slick 4-up mixes like 1 xte rb,1xpe rb, 1xpe blue , and 1 xpe 4000K w ($20.30)........ or 3 rb and 1 blue ($27.79)........ or 1 rb, 1 blue, 1 xpg s2 1c bin and 1 xpg 4000K white ($32.45). I'm not sure what a xpg s2 1c bin is..... a white I think. The 4-up or 3-up catches my eye as just another way to clean up the mounting options...less wire , less drilling,,etc. You guys are probably way ahead of me on this....just thought I would mention it in case some folks were not aware of such fun things. I feel I need to do MY part to add to the confusion...lol

[kcress]

Thanks Dirrk. Not sure why you'd want xtanythings but they certainly are a little cheaper to buy.