Hooking up a bunch of case fans in a series circuit

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bobcrotch

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I posted in another forum looking for an old thread regarding this but no one seems to remember.

What I want to do is take .10 80mm fans from teh egg for 10 bucks and use them to circulate air in my office. I know that using a regular box fan would work just as easily but thats not the point now is it? hehe

I plan to just use a regular old AT power supply to do this. I tried to find out how much power they draw but couldn't find anything really. I'm sure that a 200w or a 250w would be more than enough though.

Does anyone see any sort of flaw in my plan? I'm not very keen on this sort of thing so i don't really know, in theory it should work right?
 
You will be hooking them up in parallel, not series. Everything in a computer goes off the supply in parallel. If you are wiring them up by yourself, you will still want to wire them in parallel. Otherwise you will get unwanted voltage drop along the chain and the last fan will hardly be moving. Just run two wires the full length and tap into them where you need.

I have yet to use mine, but they are 12V 0.15A fans .. so 1.8W
they have both the molex connector and the 3-pin connector.
About a foot long wire between the fan and connectors.
Include 4 fan screws for mounting.

Any old PS should do for them. It would only be 1.5A draw on the 12V rail.
Remember that you will have to connect two of the connectors on the motherboard connector to get the supply to turn on. Been a while since I did it so I don't know which pins or what size resistor if needed. Search the forum and you should be able to find out.

Hope this helps.
 
Major_A said:
Box fan at Home Depot = $9.00.
Click to expand...

Indeed. would look better, too.
Not sure if you are going to feel much air circulation from these case fans since they are made for a small area.. like a computer case.
 
I know that using a regular box fan would work just as easily but thats not the point now is it? hehe

Maybe you didn't read the third line of my post?


Ok so running a wire the full lenght? I'm thinking 2x5 rows, so probably just run it in between the rows of fans?

Hmm would I be able to build a frame with wiring inside with femal molex connectors for the fans to plug into? Then just have one molex for the power to connect to?

Here is a retarded drawing to explain a bit better.

fans.jpg


That would run inbetween all of the fans, then have some sort of sides to hold the fans in place perhaps. How exactly would I go about wiring this? Or should I just check out how stuff works...
 
No offense, but that picture really doesn't help much ;)

I'm going to assume the fan's power cables are red and black. Connect all of the red fan wires however you like to a yellow wire from your PSU. Connect all of the black fan wires to a black wire from your PSU. Then they will be in parallel and they'll work great. You could easily do this by putting a bunch of female molex connectors in a box, and wiring them all up to a single molex which connects to the power supply. But unless you plan on taking fans in and out of the box, I would just solder it together, use wire nuts, or terminal blocks, since that's usually faster than trying to wire up 10 connectors.
 
Ok cool, i guess i should have read what you posted again before i drew this picture, since all the fans will be static in the cage. But lets asume that the molexs are somehow soldered or....something else. Like i said i'm not real certain about other electrical components, so i'll check out a site of components.

Here is a somewhat less shitty picture that might display what i'm trying to get done here. Also i found this site on slashdot the other day that machines stuff, i haven't got the cad program yet but it looks neat anyhow picture.

Do i have the right idea basicly now?

fancage.JPG
 
Why don't you just cut all the connectors off and wire them all together? That would be much cleaner than having 10 connectors in a row.
 
Ya thats pretty much what i've established at this point. The only nice part about the molex connectors would be to replace fans if the bearings get noisy or something.

This started out as a really super easy project where i was probably going to attach all the fans together with wire or something but now i'm just getting creative hehe.
 
Screw the 10x 80mm fans. You need 50x 40mm fans, now that would suck. :p I doubt that your fan project would be good for cooling your whole office but it might work pretty good for a desk fan. Maybe mount it above your monitor or something so you can get blown in the face. :D
 
Do what I did, go to radio shack and buy yourself an RCA panel with 8 connectors, and put RCA connectors on all of your fans, and wire them into a central box

Works great!
 
how big is this office?

these fans arnt going to do crap.

mod the box fan into the wall and make a custom fan grill and put it over it.
 
Terminal strip is your best bet seeing as the only work you must do to the fan is to cut off the connector and screw the wires down. If you need to replace one, all you need to do is cut the connector off like before. The only soldering that may need to be done is to the connector that your psu plugs into.

Two sided terminal strips allow you to screw down and connect 2 different things easily. Also they are designed to be screwed down to a surface, where molexes are extremely difficult to keep held down.

They come in different styles but here is a 10 position one that will work if one is placed on either side. (2 poles per fan = 5 fan connections each).
 
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