Go Back   Aquarium Advice - Aquarium Forum Community > General Aquarium Forums > DIY Projects
Click Here to Login

Join Aquarium Advice Today
Reply
 
Thread Tools Search this Thread Display Modes
Please support our sponsors and let them know you heard about them on AquariumAdvice.com
 
Old 07-21-2010, 01:04 AM   #11
Aquarium Advice Addict
 
krap101's Avatar
 
Join Date: Feb 2004
Location: Roscoe, IL
Posts: 6,084
Send a message via AIM to krap101
When I started to think about this project awhile ago, it seemed so much easier just to use a laptop power supply. I haven't thought about it (rethought) in depth yet, but I still have my original assumptions (not sure how well founded they are though)

If you're suggesting a switching mode power supply, then wouldn't I be able to ignore the resistor at the end?
__________________

__________________
~ Danny
krap101 is offline   Reply With Quote
Old 07-21-2010, 01:11 AM   #12
Aquarium Advice FINatic
 
Join Date: May 2009
Location: tallahassee, florida
Posts: 990
Quote:
Originally Posted by krap101 View Post
When I started to think about this project awhile ago, it seemed so much easier just to use a laptop power supply. I haven't thought about it (rethought) in depth yet, but I still have my original assumptions (not sure how well founded they are though)

If you're suggesting a switching mode power supply, then wouldn't I be able to ignore the resistor at the end?
Nope, youll need a resistor for any PSU you choose. Or some other way to control current.

Diodes will attempt to draw enough current to destroy themselves.

You are thinking of a PSU + controller combo such as a meanwell LED power supply.

Matt
__________________

__________________
mrg02d is offline   Reply With Quote
Old 07-21-2010, 01:27 AM   #13
Aquarium Advice Addict
 
krap101's Avatar
 
Join Date: Feb 2004
Location: Roscoe, IL
Posts: 6,084
Send a message via AIM to krap101
Now that that is out of the way (thanks ) what power supply would you recommend?

If I go for the 24, I'll need a 1.8 ohm resistor, and (.8^2*1.8 at ~1.152 watts.)

If I go for the 22, will the last led in the string just take up the slack and be dropped to 3.5V? or will it not work?

I guess I'm onto buckpucks now... Buckpucks basically make sure only 800ma (I think they only come in 700ma or 1000ma flavors) gets through, and kind of protects your leds. Beyond that, they serve the same purpose as the resistors, right? If I remember correctly, the circuit has two paths. One path is if it is over the rated current, and it goes through something and is somehow lowered, the second path somehow boosts it (capacitor?) and I saw it on instructables awhile ago.
__________________
~ Danny
krap101 is offline   Reply With Quote
Old 07-21-2010, 01:47 AM   #14
Aquarium Advice FINatic
 
Join Date: May 2009
Location: tallahassee, florida
Posts: 990
Quote:
Originally Posted by krap101 View Post
Now that that is out of the way (thanks ) what power supply would you recommend?

If I go for the 24, I'll need a 1.8 ohm resistor, and (.8^2*1.8 at ~1.152 watts.)

If I go for the 22, will the last led in the string just take up the slack and be dropped to 3.5V? or will it not work?

I guess I'm onto buckpucks now... Buckpucks basically make sure only 800ma (I think they only come in 700ma or 1000ma flavors) gets through, and kind of protects your leds. Beyond that, they serve the same purpose as the resistors, right? If I remember correctly, the circuit has two paths. One path is if it is over the rated current, and it goes through something and is somehow lowered, the second path somehow boosts it (capacitor?) and I saw it on instructables awhile ago.
To drive 12 LEDs I would go with one of these:
Nanotuners.com

It will also allow you to dim the leds. Cheaper than bukpucks and more reliable.

Matt
__________________
mrg02d is offline   Reply With Quote
Old 07-21-2010, 02:07 AM   #15
Aquarium Advice Addict
 
krap101's Avatar
 
Join Date: Feb 2004
Location: Roscoe, IL
Posts: 6,084
Send a message via AIM to krap101
So, the adjustable dimming function, that controls current right?

To me, it looks like the 60-24 will be the best option for this tank and others, as I will be able to run 3 strings of 6 leds at 800ma and 3.7v if I choose. If I get the 60-27, I'll be able to run 21 leds at ~750ma and 3.7v. If I wanted to one string of 12 leds, the 60-48 would work, but would not allow for any expansion to another string unless I pushed the leds down to 650ma.

Your thoughts on this?

Also, I read somewhere that mixing strings of leds is a bad idea, so if I wanted to add moonlights, would I have to use an entire string?
__________________
~ Danny
krap101 is offline   Reply With Quote
Old 07-21-2010, 02:17 AM   #16
Aquarium Advice FINatic
 
Join Date: May 2009
Location: tallahassee, florida
Posts: 990
Quote:
Originally Posted by krap101 View Post
So, the adjustable dimming function, that controls current right?

To me, it looks like the 60-24 will be the best option for this tank and others, as I will be able to run 3 strings of 6 leds at 800ma and 3.7v if I choose. If I get the 60-27, I'll be able to run 21 leds at ~750ma and 3.7v. If I wanted to one string of 12 leds, the 60-48 would work, but would not allow for any expansion to another string unless I pushed the leds down to 650ma.

Your thoughts on this?

Also, I read somewhere that mixing strings of leds is a bad idea, so if I wanted to add moonlights, would I have to use an entire string?
Yes, the dimming feature controls the current draw. You can look at the current/voltage curve of the LED to see what voltage it will drop at a given current draw. They ought to drop 3.7 max when drawing their maximum (safe) current.

If you are running all whites, id run one string and use one meanwell. If you have different colors and want to mix the colors (and have the money) you can use a meanwell for each string.

Each string will need its own meanwell.

Let me know what you plan to do and I will be able to help a little better.
How many leds total? How many colors? What functions do you wish?

Moonlights are a bit more tricky, as you usually just use a few. If you have a long tank and need several, then another meanwell (cheaper non dimmable version) would be a good choice.

MAtt
__________________
mrg02d is offline   Reply With Quote
Old 07-21-2010, 02:33 AM   #17
Aquarium Advice Addict
 
krap101's Avatar
 
Join Date: Feb 2004
Location: Roscoe, IL
Posts: 6,084
Send a message via AIM to krap101
Maybe moonlights aren't the best idea, since I'll be living in the dorms, and my roomate might not like the blue reflection on the ceiling.

I'm not exactly sure on how many leds I want yet.. I'm hoping to have a medium-high/high light tank, without totally burning my tank up with too much light. I forgot about the increased efficiency/watt, and the first plan was to have 12 in a 10 gallon tank (fw planted) and that would have given me 36 leds watts. The more conservative estimates are 3-4w/wled, so this might possibly give me over 100w of "real" light. If I get 6 leds, 18wled, that's 54-72 "real" watts, which is kind of but also reaching sun-like levels, if you know what I mean :P, but now I'm worried about having 4 leds over my fish tank with coverage and all... I want to do this right, but at the same time not spend more money than I need to. I've allotted maybe $40 for the leds, and now $32 or so for the meanwell, and I still haven't even considered heat sink and possibly optics costs.

I'm hoping to eventually possibly get them running on a controller like here. It seems like if I tried using an real time clock, it may make things easier.

DIY Hood for 12 gallon with moving moonlights, sunrise/sunsets, and cooling

You said I'd need a new meanwell for each string. Does this include strings of same color? I was counting on the 2.5A and the 24V, so I could run two strings of 6 or 2 strings of 7 when I try to make this project bigger (29 and 40b tanks) I'm using strings as in each branch of a parallel circuit. I'm hoping you're meaning strings as in different colors, or making a larger light will be more complicated than I thought.

I'm expecting one color (I'm not a reefer :P) using 6500k cool whites. I'm almost afraid some of the spectrum will be left out, as a side effect of how leds work, and it will wash out the color of the tank. As for total leds, I'm thinking 4-6 should work. I'm also wondering about running more leds at a lower power (current). 4 leds seems a bit low, but then again, it is only a 10 gallon.
__________________
~ Danny
krap101 is offline   Reply With Quote
Old 07-21-2010, 02:51 AM   #18
Aquarium Advice FINatic
 
Join Date: May 2009
Location: tallahassee, florida
Posts: 990
All of these led power supplies run just one string at a time. A 10g tank is going to require 16 leds or so. The main concern here is getting the light coverage. I made an LED light for my 7.5g reef that is a 12in cube. I needed 2 strings of 4 leds to cover the 144in^2 of area.

Youll wind up spending more than you think to do this right.

You are off to school, right? You should be eligible for financial aid.

I spent about $150.00 to build my light and its a bare bones light. No fancy fixture or anything to enclose it.

Matt
__________________
mrg02d is offline   Reply With Quote
Old 07-21-2010, 03:32 AM   #19
Aquarium Advice Addict
 
krap101's Avatar
 
Join Date: Feb 2004
Location: Roscoe, IL
Posts: 6,084
Send a message via AIM to krap101
I'm looking to just use the heatsink as the "fixture" and create some legs out of acrylic or something (aluminum maybe)

I'm wondering what is preventing me from running a parallel series off this driver? I'm not trying to be difficult, but I am a little surprised. After a quick search, the closest I have come to the meanwell unable to run parallel circuits was that if one led goes out, you could possibly damage the rest of them.

Power supply question - CandlePowerForums
"They're using another meanwell driver and like you said Bob, it's a 48v(max) driver but it's a bunch of watts and you can run parallel strings off of the initial series and the driver is dimmable. It's a plus for them but sounds like a pain to me."

This won't be a reef tank, so 16 leds at 3w is going to be a ton of light. I'm not sure about the angle on these leds (I'm sure there's multiple), but if I got 6 leds, would I then need optics to spread the beams out to avoid spotlighting? Is that the reason for the need for 16 or is it that the estimates for t5 equivalent wattage was a little over and maybe closer? I'm trying to get to around 3.6wpg, and from what I understand, I'll need 36 "real" watts, or 9-18 "led" watts, depending on the conversion between t8/t12 and leds. T-5ho is like 1.3:1 and t5 is like 1.35:1 or something like that. I read that leds were like 3-4:1 and what I'm basing most of this build on.

Let's start the calculations for coverage. Assume I need to cover 200in^2, and my leds will be around 14" high. My led's will have a 90 degree viewing angle (off the cree web site) so that means that (using trig) each circle will have a radius of 14". With a 90 degree viewing angle, it will be impossible to have even coverage as well as keeping all the light in the tank. I'm guessing a 2x3 formation will work well, or a 2x4 (I think this will give the most even coverage)

I'm still at a loss to how much more light (I guess par is the craze these days) that an led will produce compared to a t5ho or a t-8/t-12. If I used 16 leds (48w) over a 10 gallon, even under normal standards it is too much light, but since these are high output leds, it's worse.

Don't think I'm ungrateful, (I really am), but I'm just trying to figure this out, and I guess I learn the best when I am debating (my family gets really annoyed). People like you make people like me seem smarter than we are :P. Smartness by proximity? Virtual proximity?
__________________
~ Danny
krap101 is offline   Reply With Quote
Old 07-21-2010, 10:06 AM   #20
AA Team Emeritus
 
Jimbo7's Avatar
 
Join Date: Feb 2008
Location: Minneapolis, MN
Posts: 1,996
Quote:
Originally Posted by krap101 View Post
I'm looking to just use the heatsink as the "fixture" and create some legs out of acrylic or something (aluminum maybe)

I'm wondering what is preventing me from running a parallel series off this driver? I'm not trying to be difficult, but I am a little surprised. After a quick search, the closest I have come to the meanwell unable to run parallel circuits was that if one led goes out, you could possibly damage the rest of them.

There is another thread here when we discussed exactly why parallel series isn't your best option. Off the top of my head I can't remember exactly why, but its not. Series is the best way to do this, parallel can have fluctuations that can blow the diodes if you aren't careful.

Power supply question - CandlePowerForums
"They're using another meanwell driver and like you said Bob, it's a 48v(max) driver but it's a bunch of watts and you can run parallel strings off of the initial series and the driver is dimmable. It's a plus for them but sounds like a pain to me."

This won't be a reef tank, so 16 leds at 3w is going to be a ton of light. I'm not sure about the angle on these leds (I'm sure there's multiple), but if I got 6 leds, would I then need optics to spread the beams out to avoid spotlighting? Is that the reason for the need for 16 or is it that the estimates for t5 equivalent wattage was a little over and maybe closer? I'm trying to get to around 3.6wpg, and from what I understand, I'll need 36 "real" watts, or 9-18 "led" watts, depending on the conversion between t8/t12 and leds. T-5ho is like 1.3:1 and t5 is like 1.35:1 or something like that. I read that leds were like 3-4:1 and what I'm basing most of this build on.

16 seems pretty excessive to me. I honestly think 12 is more then enough for that size for a planted. I think you are getting hung up looking for numbers that aren't really there as far as conversions go. Let me mock up something and we can take a look at it.

Let's start the calculations for coverage. Assume I need to cover 200in^2, and my leds will be around 14" high. My led's will have a 90 degree viewing angle (off the cree web site) so that means that (using trig) each circle will have a radius of 14". With a 90 degree viewing angle, it will be impossible to have even coverage as well as keeping all the light in the tank. I'm guessing a 2x3 formation will work well, or a 2x4 (I think this will give the most even coverage)

I'm still at a loss to how much more light (I guess par is the craze these days) that an led will produce compared to a t5ho or a t-8/t-12. If I used 16 leds (48w) over a 10 gallon, even under normal standards it is too much light, but since these are high output leds, it's worse.

Again, I think 16 is way too much. I would guess you are looking at 350+ PAR where some of these beams cross over in the middle.

Don't think I'm ungrateful, (I really am), but I'm just trying to figure this out, and I guess I learn the best when I am debating (my family gets really annoyed). People like you make people like me seem smarter than we are :P. Smartness by proximity? Virtual proximity?

No worries, asking lots of questions is never a bad thing.
So..much..text.. its too earlyyy.
__________________

__________________
Links to old builds:
12DX LED Build
Frag Tank (Fixed Link)
Dorm Pico Tank
Jimbo7 is offline   Reply With Quote
Reply

Tags
10 gallon, build, build thread, co2, diy, diy co2, led

Please support our sponsors and let them know you heard about them on AquariumAdvice.com

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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 Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
My 20 gallon build thread mommytron Freshwater & Brackish - Getting Started 159 01-25-2011 09:42 PM
My 125 build thread :) divedeep1689 Saltwater Reef Aquaria 48 12-10-2009 02:29 AM
tank build thread ccCapt DIY Projects 6 01-21-2008 10:36 PM
Build thread - 180 gallon - final tank pics added 7/22 Scoot Saltwater Reef Aquaria 131 09-14-2007 09:14 PM
My First SW Tank - Build Thread Bri87swb Saltwater & Reef - Getting Started 27 12-31-2006 12:38 AM







» Photo Contest Winners








Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -4. The time now is 07:32 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.