External PSU for 140mm fan?

[oguruma]

So, the situation is I have an entertainment center that houses: my Freenas Box, my PFsense Box, my Switch, POE Switch, Wifi AP, and ISP Modem. Needless to say, that all of that stuff generates quite a bit of heat in a small enclosed space. I want to mount some 140mm fans on the back side of it. I could route some long cables out out of my FreeNAS box case, but I would like to be able to remove all of the hardware without having to do some strange maneuver to unplug the fan cable.

I have seen some fans that are powered via USB, but they are hardwired to the fan itself, and would have to discarded entirely, or cut and soldered back together when the fan craps out. I would like a good way to power a conventional 140mm case fan, that way I can replace them easier and also have the opportunity to choose a fan that is as quite as possible (the entertainment center in in the middle of the media room, so noise is something of a concern.

Anybody have any ideas? Thanks in advance for any input.

 

[Ericloewe]

If you just want full speed, just connect them to your favorite +12V DC source. A fan-to-molex adapter could be useful in this matter.

 

[BigDave]

They make this type of converter for 4pin molex.
You'll just have to look around and find one that
meets your power requirements.

 

[nightshade00013]

My simple suggestion is to find an old power supply that has crapped out and take a Molex connector from it. Then get an old wall wart that is 12V and probably at least 500MA (if you want to run the fan a little slower find a lower voltage wall wart 9v will slow the speed by around 1/2 don't skimp on the amperage though) and cut the plug off the end. Solder the two together and make a nice little cable that is covered with some heat shrink tubing. One 140MM fan should be able to be powered by it easily and if you have a higher amperage wall wart you could run a couple fans. The shorter the molex side wires are the nicer it will look IMHO.

Will be simple to replace the fan later on and if you are like me you have been saving old wall warts and connectors from old power supplies for years anyway. You will however very likely be voiding any UL warranties on the products in question and I am not responsible for any damages that may come about from shoddy duct tape and bailing wire workmanship. I have however done things like this many times with no ill effects.

 

[survive]

Hi oguruma,

Would something like this work:

http://www.performance-pcs.com/phobya-pci-slot-cover-4pin-molex-3x-3pin-fan-plug.html

-Will