DIY cooling fans

[renogaw]

Ok, so my powersupply on my computer died, and i have a couple old powersupplies hanging around (none that worked...) so i got to thinking--use the fans to make a cooling station.
so... i stripped one of the wires to the fan, and hooked it up to a 9v battery (says it works on 12v, but still worked) and voila i got a cooling fan. so, i guess my question is how do i make a 12v setup for multiple cooling fans? I understand low voltage 24v wiring, so i assume just get a transformer and wire a couple of them in series? or would one fan over the sump work ok?

 

[threed240]

Originally Posted by renogaw
Ok, so my powersupply on my computer died, and i have a couple old powersupplies hanging around (none that worked...) so i got to thinking--use the fans to make a cooling station.
so... i stripped one of the wires to the fan, and hooked it up to a 9v battery (says it works on 12v, but still worked) and voila i got a cooling fan. so, i guess my question is how do i make a 12v setup for multiple cooling fans? I understand low voltage 24v wiring, so i assume just get a transformer and wire a couple of them in series? or would one fan over the sump work ok?
Get a 12v power supply. You can get them from almost any electronics store. I use one for a CB radio station to run 4-4" 12v fans.

 

[threed240]

A computer power supply won't work without some modding. It needs the motherboard to work.

 

[moneyman]

You can try this to get your ATX power supply working w/o mb: http://www.bluemax.net/techtips/ATXP...pplyWiring.htm. I have not done this but will try once my current transformer dies.
Connect your fans to a 12V transformer in parallel (not series). On the fan is power usage in watts. Add the wattages of the 2 fans together. Buy a 12V AC/DC transformer that that can drive at that wattage.

 

[renogaw]

little trip to radio shack then? so for a 75 gallon without a hood, how many fans should i look into? should i just blow over the fuge instead?

 

[scsinet]

Jameco electronics sells some desktop switching supplies that will work well for this application if modifying a PC power supply isn't your thing. Part number 1586146 is a 12v@3a unit that will run at least two big fans, and probably 3+ smaller ones, depending on the watt draw of the fans, it's about $20.
Since power supplies are rated in amps usually and fans are sometimes in watts, divide the number of watts by the number of volts to get amps, so 12w at 12v is 1amp, or 4w at 12v is 1/3 amp.
Also, many fans run much quieter at a slight decrease in airflow at lower voltages, so 9 volt supplies are an alternative.

 

[renogaw]

thanks the fan was pretty quiet when i used the 9v battery, i'm actually thinking of trying to find a snap connector and splice the wires and just use a 9v battery

 

[thangbom]

i suggest you go out and get a adjustable adapter ( i have one that do 1.5v -12v) that way you can adjusy your fan speed if you need to.. just switch it to a lower v to move less air or turn it 12v for full... i bought mine from 'Fry's' for like $12
YzGyz

 

[jamparty]

aquatek makes these... you can find them on ---- for cheaper too.
http://www.aquatek-california.com/

 

[npage]

Originally Posted by Threed240
A computer power supply won't work without some modding. It needs the motherboard to work.
Use this mod on an old powersupply ATX Jumper
Or buy one 24pin power supply starter with jump wire
Using an old powersupply to control your fans also allows you to add a fan speed controller

 

[renogaw]

Originally Posted by NPage
Use this mod on an old powersupply ATX Jumper
Or buy one 24pin power supply starter with jump wire
Using an old powersupply to control your fans also allows you to add a fan speed controller

neither power supplies worked any more, so i just stole the fans out and threw the rest away. that is a pretty good idea though and now i know how to test to see if a powersupply is actually bad or not!