DIY fans with computer controller help

I'm going to be adding some fans to my canopy. Thermaltake Silent Cat 120mms. I planned on wiring the fans to a switchable 3,6,9.6,12v universal power supply so I can change the fans speed on the fly. A local reefer suggested a cheap computer fan controller.

So....The fans I will be buying have 3 pin molex connectors which will plug directly into most basic computer fan controllers. Any basic cheap multi fan controller will suffice. Here is an example:
Ultra Products ULT-40061 Over Clock Multi-Fan Controller Computer Case Fan in Computer Fans and Coolers at JR.com

It says that the controller needs to be run off of 5v input voltage which I assume is the standard 4 pin molex connector that would draw 5v from your motherboard. Is there any way to wire the 4 pin molex to an external 5v power supply instead of the motherboard? I'm trying to do this with what I have but it sounds like I have to get the 4 pin molex AC adapter for another 20 bucks?.....any thoughts or ideas? Anyone else build a fan controller?

 

cool idea for the use of fans.. Bump

 

Looks like I will be ordering a 5v 4pin molex AC/DC adapter. ebay had them for cheap.

 

So I got everything ordered on 9/7/09:

From Amazon.com $30 total with free s&h
-(2) Thermaltake Silent Cat 120mm fans
-5v Molex HDD adapter power supply (power for my computer fan controller that has a molex connector to plug into a co,)

From ebay $8 free s&h from hongkong (supposed to arrive within 6 business days)
-4 Fan controller with LEDs

$38 total. Hopefully this works. I'll get up some pics when everything arrives. But for now, here are some stock photos of my orders.



It should look very clean and neat when I am finished. I plan on doing a black mesh back and attaching the fans using zipties so i can easily remove them without unscrewing, and the mesh will give it that much more ventilation. I also have 2 quiet 80mm fans that will be added as well. My canopy for my 72 is finally coming together!

 

Well the fan controller works, fans blast but are completely silent even when on full load. Keeps the t5s very cool. Dropped my tank temp from 79 to 74 in 24 hours. My evaporation has increased from about 1/4 gallon per day to a gallon a day. I am now forced to top off daily vs every 3 days. The fans and the canopy turned out very nice.

Fan Controller Project cost 40 bucks and was very simple to complete. If anyone would like further details on the wiring or anything about the project, let me know. For some reason there doesn't seem to be too much interest in a DIY fan controller. Must not be too many people with canopys! I'll try to get some pics up I just can't figure out where to mount the controller.

 

I want to do this. Will pm you !

 

PM replied to...

This is still working great today, been a month and a half, no issues. Cools closed canopy great, t5 fixtures are slightly warm. I would recommend to anyone.

 

What a great idea, I was planning on doing something similar, but using a nicer digital fan controller with temp readouts and RPM display.



I think that would look cool in the middle of a hood, but then again, I'm also quite a nerd.

 

This is sweet. Im am going to do this in the next few weeks...

K+

 

I wanted to do something a little more fancy, but my problem was I was trying to make this as cheap as possible. I don't know about putting the controller right in front of the canopy. Might be a little distracting. That is a problem I am having, not really sure where to put the controller. I just have it hanging so its not sitting on the bottom of my stand near my sump. I'll think of something.

Someone PMed me because they were planning on purchasing the coralife 120v fans instead, then saw my thread. The single fans that plug into the wall are not going to be nearly as silent as this DIY. I doubt they push as much air too. And with the DIY you have the option to get different sized fans and speed/slow the rpms to silence them.

The main thing I would've done differently with this DIY is get a better controller. I want one that turns off when the temp drops, one that has a temp probe. I have so much evaporation going on, its rediculous! I plan on just putting the fans on a timer and having them turn off right after my actinics.