How can I power my fans externally?

Tickles14

Honorable
Feb 13, 2014
20
0
10,510
Hi,

I'm trying to run my 12v DC fans externally. Is there a way to do this? Is there such thing as a power supply specifically for 12v fans? I'm thinking the only way to do this is to cut up a 12v power supply that I can get from the shops. Is there another way to power them? Is there anything that can externally supply the correct voltage (12v) to these fans?

Thanks, really appreciate any help.
 


Who said anything about a PC? 😉

It's a micro refrigerator fan, the current fan is noisy as hell and it's 5v, I can only find quiet 12v fans. So I need a way to get 12 volts of power to the fan externally. I don't want the fan to ever power off as it will be running 24/7.
 


I'm with this guy. Power them off the PSU using a Molex plug with an adapter if necessary. Most cases have ports int the back you can run the wiring through. Or, take this as an opportunity to do a little custom modding and drill some holes where needed. With the Molex running the fans you could split it and throw on some custom LEDs while you're at it. Search Amazon for LED strips, it's easy and quick, and looks great. Your buddies will be jealous.
 


This would have been the best answer if I was asking for a PC. Please read my reply to his post, it will clear things up :)

 
You can spice any old 12v adapter, but the key is to try to match the amp draw. Most wall-wart adapters from routers and cell phones, etc, all usually use an unregulated power supply. Say a 12v 500ma adapter, with no load just measured with a multimeter will provide about 14-15v. when the 500ma is used, by whatever the device it came from is used, the voltage drops to 12v. if you try to use 1a worth of power, it drop down to 9-10v.

So the key when taking an old router wall plug and using it to power something for 12v is to match the amps the closest you can. Too little and you'll get more than 12v, too much and you'll get less.
 


*foot in mouth*