Computer power supply to power cooling fans, good idea?

[eng55]

I am having heat problems in my stand and was wondering if it would be ok to use an old computer power supply to power four 120mm cooling fans. Two on each end of the stand. I know that there is a way of doing it with an ac adapter but was wondering if this would work since I could find an old pc power supply for pretty cheap and wouldnt have to worry about the wiring getting messed up.
Thanks
E

 

[ErikS]

It will work fine provided you don't put the PS near where it can get damp.

It's just overkill - you'll be burning a lot of extra power to get the fans going.

 

[eng55]

Ya thats what I figured, my buddy who helps me out with some of my projects suggested it to me and was all gung ho about the idea. I told him that I would post on here and see what people said. I also figured that would be a lot of power wasted, also would put some more heat in the stand as well.
Thanks
E

 

[thereefmaster]

That is a great idea. Wish I would have thought of that. Are you gonna use like a 250-300W or something?

HTH

Nate

 

[eng55]

Ya thats what we were thinking of using, something around that size. The only problem would be like ErikS said, keeping it in a place where moisture wouldnt reach it. I dont know if the cords on the fans and power supply would be long enough to house the power supply out of the stand. Therefore elminating the possibility of any moisture coming into contact with it and also the power supply adding even more heat to the stand.
E

 

[alpine]

It would actually be cheaper to use an ac adapter as they are relatively cheap new and even cheaper used.Just make sure that the adapter has enough voltage & amps to fully power the fans.I have about 20 adapters that I use for one thing or another.

HTH
Jorge

 

[thesaent14]

i have like 10 powersuplys for computer and i did the wireing to turn on with out the motherbore any one intrest it they work really good with 12v fans you can add like 15 fans depending on the pws

 

[hyperfocal]

It is incredible overkill -- I'm with alpine, use a recycled 12v wall-wart power adapter.

 

[tekknoschtev]

<a href=showthread.php?s=&postid=6688297#post6688297 target=_blank>Originally posted</a> by alpine
It would actually be cheaper to use an ac adapter as they are relatively cheap new and even cheaper used.Just make sure that the adapter has enough voltage & amps to fully power the fans.I have about 20 adapters that I use for one thing or another.

HTH
Jorge

Unless you belong to my family when theres more PSUs than you know what to do with.

We ended up powering 4 80mm fans with our PSU (250W). We had the PSU in the stand, and while doing some freshwater testing of our plumbing managed to overflow the tank and it filled up in the PSU. Not a good thing.

I still intend on getting another PSU to power the 4 fans in the canopy as during the summer, even with two 6" desk fans on the canopy, the temperature gets mighty warm. When we had the canopy vented with the fans it helped tremendously. On top of the fans, we were going to install moonlights and a few other things as well (ie. changing a battery operated thermometer over to the PSUs power). I think its a ver viable solution if you've got a PSU laying around, but if not, as others have said, purchasing a 12V power adapter would be cheaper if you had to buy new.

 

[hyperfocal]

Switching power supplies like those used in computers generate a lot of waste heat. Many come equipped with their own internal fans to keep them cool. That heat is money just thrown away, plus if the power supply is near your sump it'll contribute to tank overheating. Of course, you could always add a chiller to compensate ;-)

I suppose a laptop power supply might be a better choice than a desktop, but you'd be ahead of the game even if you went out to Radio Shack and bought an adapter off-the-shelf. If I recall correctly, a small (like 4") 12v fan pulls about 250mA, so you can easily run a couple of them plus a LED Moonlight set off a 1.2A adapter...

 

[charles-dixon]

I tried doing what you are talking about... using a power supply from a computer. Good idea, but you will need to figure out which wires need to go to what. other wise it will not work without a motherboard.

 

[charles-dixon]

oh and i forgot to mention.. I went to a local thrift store in search of 12v power adapters. I was able to find 15 and the store gave them to me for $3.75 + tax. So go check out your local thrift stores, goodwill etc.

 

[thesaent14]

<a href=showthread.php?s=&postid=6689931#post6689931 target=_blank>Originally posted</a> by charles-dixon
I tried doing what you are talking about... using a power supply from a computer. Good idea, but you will need to figure out which wires need to go to what. other wise it will not work without a motherboard.

thats what i did i know how to do it with out the mdbore

 

[SuperDodge]

Be sure you use an appropriatly sized power resistor to create a "dummy load" or the power supply won't be stable.

 

[supertech3]

Just use like some of the others stated the small wall ac/dc power supplies there are many sizes just make sure you find the specs for your fans like amp rating and add them up (ie. 2 fans 150 mamp each equals 300mamp ttl) then look for a p/s that will handle this.

 

[Sm0kin]

i have found fans used inside tanning beds are good for cooling. I have 2 of them built into my light canopy they work well on cooling but kinda loud.