Reef Central Online Community

Go Back   Reef Central Online Community > General Interest Forums > Do It Yourself
Blogs FAQ Calendar Mark Forums Read

Notices

User Tag List

Reply
Thread Tools
Unread 02/16/2011, 11:14 AM   #51
RTMA
DIY Fanatic
 
RTMA's Avatar
 
Join Date: Feb 2009
Location: Norwalk
Posts: 1,164
Very nice build - wish I had access to a cnc. Although, sorry to say, I think if you add optics, those bends may be rendered useless. Tagging along - can't wait to see the finished product.


__________________
Joe

Current Tank Info: SPS Dominated In wall 180 (4x3) | SRO XP2000 EXT | Water Blaster powered Seaswirl | MP40 & Tunze Flow | Geisemann Matrix II Dimtec | RKE Managed
RTMA is offline   Reply With Quote
Unread 02/16/2011, 11:19 AM   #52
JW65
Registered Member
 
Join Date: Dec 2010
Location: Catawissa, PA
Posts: 124
That is awesome! Cant wait to see it in action! I am thinking about a DIY led build and this just gave me some good ideas for when I finally start it.


JW65 is offline   Reply With Quote
Unread 02/16/2011, 11:26 AM   #53
ktg113
Registered Member
 
ktg113's Avatar
 
Join Date: Jan 2010
Location: West Palm BEach
Posts: 438
I forget what Cnc stands for but basically it is a nice toy I mean tool that takes a auto cad drawing and then makes all the cuts that are in the auto cad drawing


Sent from my iPhone using Tapatalk


ktg113 is offline   Reply With Quote
Unread 02/16/2011, 11:38 AM   #54
jpccusa
Registered Member
 
Join Date: Jan 2008
Location: Orange County, CA
Posts: 151
Quote:
Originally Posted by skimate View Post
Iím a little concerned that bending those tabs may have slightly distorted the area where the LEDís are fixed, possibly creating a tiny void under them?
Quote:
Originally Posted by smithj108 View Post
Agreed!!!!!!! It looks like there's a slight bow - but it could be just camera optics in the picture.
I believe there is thermal compound under each star... that would fill the void.


__________________
JP
* Hundred gallons FOWLR and 'shrooms
* DIY LED (http://reefcentral.com/forums/showthread.php?t=1973462)
* 10g sump w/ protein skimmer * 8g refugium w/ Chaeto
jpccusa is offline   Reply With Quote
Unread 02/16/2011, 12:02 PM   #55
sfsuphysics
Registered Member
 
Join Date: Jan 2004
Location: San Francisco
Posts: 9,103
Quote:
Originally Posted by jpccusa View Post
I believe there is thermal compound under each star... that would fill the void.
Yeah but thermal compound is meant for very tiny gaps not huge ones, of course I haven't used thermal compound in a long time maybe it actually transfers heat better than it used to

One thing to help with the bending, maybe on version 2.0 Since you have the CNC why not grind down a channel along the bend area that's 1/32 or so so the bend doesn't take as much effort? Nifty little setting you have, on my man-list for things I'd like.

Also I know by the looks of the wiring, the jumper popped out at me, are you running two strings in parallel? I'm assuming the fuse and the resistors are for that? I'd like to see the specs on those fuses/resistors when you have the chance.


__________________
Mike
sfsuphysics is offline   Reply With Quote
Unread 02/16/2011, 01:16 PM   #56
westreef
Lost as usual
 
westreef's Avatar
 
Join Date: Jul 2010
Location: Really California?
Posts: 846
Kcress,
I think your resistors are for the current monitoring purposes. Is it 1 ohm resistors? From the look of it, it is about a watt or less. In my LED built, I use 1 ohm 5 watts wire-wound resistors and I can still feel they are quite warm to the touch with 1 Amp going through it. Just curious.
BTW, very nice built!


__________________
Bernie

75g, ATI 4x58wT5 LED Hybrid Powermodule, AquaMaxx ConeS 1, 2xMP40wES, RKL controller, Tunze Osmolator
westreef is offline   Reply With Quote
Unread 02/16/2011, 03:11 PM   #57
Spaced Cowboy
South Bay Reefer
 
Spaced Cowboy's Avatar
 
Join Date: Sep 2006
Location: San Jose, CA
Posts: 395
Blog Entries: 29
Quote:
Originally Posted by westreef View Post
Kcress, sorry to ask: What is CNC?
CNC = "Computer Numeric Control". It's basically a way of controlling a device from a computer. Typically you use a CAD (Computer Aided Design) program to draw something on the computer, and then go through some process (it varies depending on what you want to do) which results in a file you can send to a CNC device (typically a router, on an X,Y,Z table, that describes where in space to move the router, and how fast the spindle ought to be rotating etc.). It's all numbers, hence the acronym.

Beware, these things are addictive. I now have 3 of them...

- A PCB "engraving" machine that starts off with a sheet of copper-clad FR4, and "rubs out" the copper, leaving behind a circuit to which you can attach components. It's accurate down to about 6/1000 of an inch - which is to say it can create "wires" only 6/1000 of an inch wide connecting pins on ICs. I use it a lot

- A traditional CNC machine made by K2 - see http://k2cnc.com. This is actually still awaiting software to use it fully. I intend to use it when I get around to making housings for my reef controller.

- A Thing-o-matic from http://makerbot.com/ which allows me to "print" in plastic, making a 3D object. This is an additive CNC machine (it deposit plastic, one layer after another, to form the model) whereas the other two are subtractive CNC machines (they route away material from a solid block, leaving behind the desired model).

If someone says "CNC machine" without any qualification, they're almost always talking about a router on an X,Y,Z table, so it's a subtractive device.

Hope that clears things up

Simon


Spaced Cowboy is offline   Reply With Quote
Unread 02/16/2011, 04:50 PM   #58
kcress
Registered Member
 
kcress's Avatar
 
Join Date: Dec 2007
Location: Central California Coast.
Posts: 5,383
What exactly are you using for your PCB machine? I'm always interested in that subject.


kcress is offline   Reply With Quote
Unread 02/16/2011, 05:00 PM   #59
westreef
Lost as usual
 
westreef's Avatar
 
Join Date: Jul 2010
Location: Really California?
Posts: 846
Thanks Spaced Cowboy. Very clear.


__________________
Bernie

75g, ATI 4x58wT5 LED Hybrid Powermodule, AquaMaxx ConeS 1, 2xMP40wES, RKL controller, Tunze Osmolator
westreef is offline   Reply With Quote
Unread 02/16/2011, 05:05 PM   #60
Rybren
Registered Member
 
Rybren's Avatar
 
Join Date: Apr 2009
Location: Ottawa, Canada
Posts: 1,642
kcress,

I'm curious as to why you didn't go with your DIY Driver? Did you ever end up building a rig with it?


__________________
120G Mixed Reef, 28G AIO zoa/pipefish tank
Rybren is offline   Reply With Quote
Unread 02/16/2011, 05:16 PM   #61
Spaced Cowboy
South Bay Reefer
 
Spaced Cowboy's Avatar
 
Join Date: Sep 2006
Location: San Jose, CA
Posts: 395
Blog Entries: 29
Quote:
Originally Posted by kcress View Post
What exactly are you using for your PCB machine? I'm always interested in that subject.
It's an EverPrecision EP2002H with a controllable (60,000 rpm max) spindle. You can see the specs at http://everprecision.com/e-epseries-3.html - that's for the 2006 model, but its essentially the same device. Mine claims 4-mil accuracy as well, but on a test grid, only about 50% of the traces actually conducted at 4 mil. At 6 mil, they all did. I don't need better-than-6-mil accuracy, so I'm ok with that.

One of the reasons it repeatedly works at that resolution is that it does a surface-scan of the copper before it mills away the surface. I attach a GND-lead to the copper top, and the toolhead makes an electrical connection as soon as it touches the copper. That gives it a very sensitive measurement of height variations in the FR4, and you can see it compensating in Z as the toolhead moves across the surface when milling. Very cool.

I think the machine itself is excellent, but the service frankly sucks. The current dealer won't upgrade my software because I bought it from the previous dealer... EverPrecision themselves don't want to get involved, so basically I'm stuck with the old software. Fortunately, that software is pretty good, and I'm unlikely to need an upgrade. If the worst comes to the worst, I guess I can write something - it's all just g-code, and I am a software engineer

Simon.


Spaced Cowboy is offline   Reply With Quote
Unread 02/16/2011, 06:16 PM   #62
kcress
Registered Member
 
kcress's Avatar
 
Join Date: Dec 2007
Location: Central California Coast.
Posts: 5,383
Quote:
Originally Posted by Rybren View Post
kcress,

I'm curious as to why you didn't go with your DIY Driver? Did you ever end up building a rig with it?
Dear sir I think you have me confused with DWZM. I've built no LED driver I've shown in RC.


Spaced Cowboy; Thanks for the info. I'll PM you so we don't run this baby off-the rails any further.


kcress is offline   Reply With Quote
Unread 02/16/2011, 09:30 PM   #63
Rybren
Registered Member
 
Rybren's Avatar
 
Join Date: Apr 2009
Location: Ottawa, Canada
Posts: 1,642
Quote:
Originally Posted by kcress View Post
Dear sir I think you have me confused with DWZM. I've built no LED driver I've shown in RC.

My bad.

I was thinking of the LED Lighting on a budget thread that you started here http://www.reefcentral.com/forums/sh...diy+led+driver


__________________
120G Mixed Reef, 28G AIO zoa/pipefish tank
Rybren is offline   Reply With Quote
Unread 02/21/2011, 05:31 AM   #64
kcress
Registered Member
 
kcress's Avatar
 
Join Date: Dec 2007
Location: Central California Coast.
Posts: 5,383
Picking up were we left off.
I want to go back a bit and show the fire-up process of a parallel string build.

Once you have everything wired up you need to check your wiring. You should really NEVER turn on a build and have parts of strings not correctly go on. That's really bad form. So the first thing you do is use a DMM with a diode test. Set it to DIODE and run down every single LED. Touch the solder blobs not the other pads. We don't care about the other pads, we only care about the ones we actually used. (Sorry for the hazy pictures the camera focused on my fingers!!)

Here I probe a blue LED in the proper direction and you can see it lights up. If it doesn't you have a problem. You could also do this with the two AA batteries method.



Next I move one probe to the chassis leaving the other in place. If I botched something that shorted the other lead to the chassis the LED will light up again - incorrectly.



Then I go back across the LED to light it up again and swap the opposite probe to the chassis to check for a short on the other side of the LED. Do this on every single LED on your build before powering up. It takes only a few minutes and will prevent any ugly, expensive, surprises.



That done we can move on to adjusting the driver. I turn the current limit allllll the way down. Sometimes they ship them all the way up. If they do this and your strings are badly balanced you could toast one. If you turn it all the way down you likely won't toast anything even with horribly mismatched strings.



Also take the time to turn the voltage limit all the way down too. This is a safety thing that can also save you in a mess up. Large currents tend to require higher voltages. Turning the voltage limit down limits the current that can occur through a secondary aspect.




kcress is offline   Reply With Quote
Unread 02/21/2011, 05:33 AM   #65
kcress
Registered Member
 
kcress's Avatar
 
Join Date: Dec 2007
Location: Central California Coast.
Posts: 5,383
The moment of truth!

Flame - on!

Immediately - if not sooner - measure the current thru the strings. You need to know if you are over driving a string so you can power down if you have to.

So, quickly, quickly, I measure one string.
I have 0.1 ohm resistors so I have to do some math. Notice the meter is set to show a maximum of 300mV. This means I'm seeing 43.8mV. Multiplying this by 10 because of my resistor values, tells me I have 438mA running thru the left string. This is great, not too much.



Over to the right string...
425mA

Wow. Happy days! They are very close together in current. Close enough that I don't have to do anything about it.. At this point I turn the voltage limit back up all the way. (more on that later)




This means I can just turn up the current to where I want to run at.
And so I do. I crank it up to 754mA on this side.



And that gives 740mA on the other side. No problems here.

Everything looks good. So now I turn down the voltage limit again while monitoring the current in one of the strings. I turn down the limit until I see the current start to drop. I then turn the limit back up until the drop disappears again. Then I turn it up a tiny bit more to cover temperature and age drifts. However in this particular build I could turn the voltage limit all the way down and never had the current drop! This means these string's Vf totals are so low that the driver voltage needed to reach 750mA is even below the voltage limit range. Perhaps I could've run another LED in each string..



The astute reader will note that this 1.3A driver appears to be delivering 748mA + 754mA which equals 1.5A.
How can this be?!
There are two reasons. One is that our drivers are really power drivers at their cores. Since this is only 12 LEDs they are not demanding anywhere near 48V to run at this current level. This means the driver can provide a little more current and still be below the 60W rating.
Another reason is probably the ripple. My meter reads the RMS current. That means it's looking at the peaks and averaging them. There are peaks with this driver.

What are they? Let's look. Setting my meter to AC Volts will show the AC current running in my strings.

Here we see 12mV (note this meter doesn't have a 300mV AC setting).

Back to my multiplying by 10. This means each string has about 120mA of ripple current running thru them. So my average current is about 750mA and this means I really have a cycling value of about 690mA to 810mA.

So, several hundred or thousand times a second my strings have the current varying thru them between those two values. This is well below the current limit for these LEDs and so does not concern me in the least. Ultimately this will make them run probably 1 or 2 degrees warmer than a totally smooth 750mA pure DC current would. If this build was running right at the maximum current limit the heating would be greater and might need further study. In this 750mA case - not at all.

At this point



On to checking out the light! Here's the color against a white ceiling. Note the slight blue.




Here's a mug shot of it.



Here's a shot with the camera stopped way down running a 1/4000 sec shutter. This really shows the LED colors. Neutral whites, cool whites, and royal blues.



Here it is tipped up lighting my towel.



Here it is for chuckles propped up on two books lighting my big build.

It fell off the books into the bottom of the tank and never blinked. Try that will a running MH and see what happens... LOL




kcress is offline   Reply With Quote
Unread 02/21/2011, 05:47 AM   #66
tahiriqbal
Sialkot
 
tahiriqbal's Avatar
 
Join Date: Sep 2008
Location: Manchester England UK
Posts: 684
Nice work sir..... quality DIY but still need a sharp heatsink to keep everything cool unless its a test run, love the whole idea behind custom reflectors


__________________
Tahir Iqbal
Manchester UK

Current Tank Info: 56cm x 56cm x 56cm
tahiriqbal is offline   Reply With Quote
Unread 02/21/2011, 08:50 AM   #67
widmer
Drug Enthusiast
 
widmer's Avatar
 
Join Date: Oct 2007
Location: Rochester, MN
Posts: 2,958
Color @ last pic looks great to me. So what's your plan? Going to make a couple more? Same color mix?


widmer is offline   Reply With Quote
Unread 02/21/2011, 10:25 AM   #68
skimate
Registered Member
 
Join Date: Feb 2004
Location: UK
Posts: 52
Absolutely fantastic!
Iím pleased to see that driver worked out.

Thanks for taking the time to show the set up process in so much detail. How to test the ripple was especially useful. Iím now not so nervous about testing the ripple monster drivers I have.

Itís so hard to tell from a photo, what do you think of the colour mix you have there?


skimate is offline   Reply With Quote
Unread 02/21/2011, 11:29 AM   #69
BeanAnimal
Registered Member
 
Join Date: Feb 2003
Location: Pittsburgh
Posts: 20,772
Would you stop messin around and put some fish in that thing already...


BeanAnimal is offline   Reply With Quote
Unread 02/21/2011, 03:30 PM   #70
kcress
Registered Member
 
kcress's Avatar
 
Join Date: Dec 2007
Location: Central California Coast.
Posts: 5,383
Quote:
Originally Posted by tahiriqbal View Post
but still need a sharp heatsink to keep everything cool unless its a test run
Hi tahiriqbal. Not sure what what you're getting at here. This is it. This is the heatsink. This is what's been runnig for a week. I'm running a temp test right now and will let you know.

Quote:
Originally Posted by widmer View Post
Color @ last pic looks great to me. So what's your plan? Going to make a couple more? Same color mix?
Not sure. Of course I'd need about 5 of these for my tank and optics are also a definite requirement. But then I also have to avoid the solar beam paths. I will likely use this style for for whatever I end up doing. Perhaps a giant one with two holes for the sun? This one was sort of spec'd to be an ATS light.. But man.. I do love the color for the livingroom as does everyone who sees it.


Quote:
Originally Posted by skimate View Post
Absolutely fantastic!
Iím pleased to see that driver worked out.

Thanks for taking the time to show the set up process in so much detail. How to test the ripple was especially useful. Iím now not so nervous about testing the ripple monster drivers I have.

Itís so hard to tell from a photo, what do you think of the colour mix you have there?
I really love the color. Realllly love it. But since I have no coral I can't really speak for its coral 'popping' ability.

After seeing the ripple result here I don't think I'd worry about it further, if you're going to run around the 7-900mA region. I was really fearing it would be causing 500mA current ripple or worse. Having sub 200mA ripple is a don't-care. As a person I am exceedingly flicker annoyed. I see flicker where no one else does. There are stores I can't even go into because of their lighting. These drivers run at such a high frequency that the actual light modulation this ripple causes is completely undetectable. It's likely way too fast for any aquarium inhabitants to respond to. Go ahead and let your ripple monsters out of the closet.

Quote:
Originally Posted by BeanAnimal View Post
Would you stop messin around and put some fish in that thing already...
??? And end up with fish poop all over my nice rock? Never!! I'm switching to Terrarium Central...


kcress is offline   Reply With Quote
Unread 02/21/2011, 06:59 PM   #71
BeanAnimal
Registered Member
 
Join Date: Feb 2003
Location: Pittsburgh
Posts: 20,772
I would just get drunk and sleep in it to reassure the wife that it will get done when it gets done

Did you steel my bench supply and meters? Do you want my variac too?


BeanAnimal is offline   Reply With Quote
Unread 02/21/2011, 07:12 PM   #72
sfsuphysics
Registered Member
 
Join Date: Jan 2004
Location: San Francisco
Posts: 9,103
Looks good, just curious if its fish only why would you need more than one? Looks like it has decent cover as it is.

Also good to know about the diode tester, had no idea it would actually light the led, I simply used a wall wart hooked to a decade box (with a ton of resistance) to make sure each fired pre-wiring.


__________________
Mike
sfsuphysics is offline   Reply With Quote
Unread 02/22/2011, 02:22 AM   #73
kcress
Registered Member
 
kcress's Avatar
 
Join Date: Dec 2007
Location: Central California Coast.
Posts: 5,383
Quote:
Originally Posted by BeanAnimal View Post
I would just get drunk and sleep in it to reassure the wife that it will get done when it gets done

Did you steel my bench supply and meters? Do you want my variac too?
Why yes I would like your Variac too. Mine's a huge one for mounting in a stage lighting panel - that's not mounted in a panel. So I have to prop it up and be v e r y careful of where I touch it.

Quote:
Originally Posted by sfsuphysics View Post
Looks good, just curious if its fish only why would you need more than one? Looks like it has decent cover as it is.
I agree. I think it would be fine, as is, (maybe without the books holding it up ), for a FO tank.
I'm going for a coral tank this time around.

Quote:
Originally Posted by sfsuphysics View Post
Also good to know about the diode tester, had no idea it would actually light the led, I simply used a wall wart hooked to a decade box (with a ton of resistance) to make sure each fired pre-wiring.
Yeah, they all light up on Diode Test. It's nice. You have to be careful using a wallwart as these LEDs have a low reverse voltage. Resistors or not you could possibly exceed the reverse voltage and damage the LEDs. Remember that the circuit open is where all the voltage is. You could have high resistor values and you will still have the total WW voltage appear across a reversed LED.

A meter keeps the diode test voltage low enough that it won't do this. If you do use a WW you should probably try to keep it around 5V.


kcress is offline   Reply With Quote
Unread 02/22/2011, 06:52 AM   #74
smithj108
Registered Member
 
smithj108's Avatar
 
Join Date: Dec 2005
Location: Tampa, FL
Posts: 98
Quote:
Originally Posted by kcress View Post
..... I see flicker where no one else does. There are stores I can't even go into because of their lighting. These drivers run at such a high frequency that the actual light modulation this ripple causes is completely undetectable. It's likely way too fast for any aquarium inhabitants to respond to. Go ahead and let your ripple monsters out of the closet.
Yes. Without a scope I would have to guess at somewhere around ~500Hz or more. Contrast that with the 60Hz you commonly see in store lights.


smithj108 is offline   Reply With Quote
Unread 02/22/2011, 07:10 AM   #75
nauticac4
Baby Fish Wrangler
 
nauticac4's Avatar
 
Join Date: Apr 2007
Location: Greenville, NC
Posts: 1,237
Out of curiosity why bend the fins down instead of up. I suppose it doesn't make much difference in heat managment, but I also dont see it impacting the light as much either. Any chance of PAR readings and some running surface temps?

Regardless the rig looks awesome can't wait to see it enclosed.


__________________
Put Wings on it and Let it Fly!!!

PBITAWA !!!

Current Tank Info: 180 Cube 3x3x3. 29Gallon Sump 20 Gallon Fuge (1) Lumenarc Reflector w. 250W ARO Ballast and - Modded GS1 Skimmer - Eheim 1262 Return - Vortech MP40W and Swirler Stein
nauticac4 is offline   Reply With Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Successful DIY LED fixture build... powdr_dayz Do It Yourself 8 10/14/2012 12:49 AM
Easy Beginner LED Fixture Build Movies Bzar Do It Yourself 14 08/17/2011 06:38 PM
Joe's 48" LED fixture build - Coming Soon! RTMA Aquarium Reef Keepers of Southwest Connecticut 50 04/08/2011 10:39 AM
24" LED Fixture Build Chrishew09 Do It Yourself 15 10/05/2010 08:10 PM
Extra LED fixtures dipan Lighting, Filtration & Other Equipment 4 04/07/2010 08:02 PM


All times are GMT -6. The time now is 12:28 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2023, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2023 Axivo Inc.
Use of this web site is subject to the terms and conditions described in the user agreement.
Reef CentralTM Reef Central, LLC. Copyright ©1999-2022
User Alert System provided by Advanced User Tagging v3.3.0 (Pro) - vBulletin Mods & Addons Copyright © 2023 DragonByte Technologies Ltd.