I have an entertainment center that runs a bit hot and I want to hook up some PC case fans to an AC adapter to cool it. I'm really worried that if I do, this the set-up could cause a fire; so please tell me if you all think this would be a safe rig.

Here's the basic plan:

http://img373.imageshack.us/my.php?image=fansetuphn2.jpg

The fans I'm using are 12v, 100mA. And I'll be getting a 12v 500mA adapter. As you can see in the pic I plan to strip the wires from everything and solder all the fan negatives to the adapter negative and all the fan positives to the ac positive. Then I'll wrap it all up tightly in electrical tape, and plug it in.

Would this work safely?

That should work. But just to be on the safe side I'd check the adapter every half hour or so for a couple hours when you first start using it to make sure it doesn't heat up too much. It should be ok but you never know.

And use heat shrink tubing, not tape, if you're planning on using this thing for a while.

got 3 running off adapters 1 is on 24\7 . I run everything that uses batteries off adapters too. no prob's

That should work. But just to be on the safe side I'd check the adapter every half hour or so for a couple hours when you first start using it to make sure it doesn't heat up too much. It should be ok but you never know.

And use heat shrink tubing, not tape, if you're planning on using this thing for a while.
500mA is plenty for 3 fans - they draw very little current.

It's pretty hard to cause a fire with a low power AC adaptor like that. Even a dead short will only result in the internal fuse blowing or a recifier diode popping.

Im actually thinking about replacing my PSU with wall warts.

Anyone know what the yellow wire on the fans is for, and what I should do with it?

Heh, I did this a few weeks ago when I noticed my amp got untouchably hot.

Added 2 80mm computer fans between it and the dvd/vhs player on top of it (Yeah, I realize this is why it was so hot, but no other place to put it).

Although, I should probably put the fans on the side of it, since hot air rises...




Anyone know what the yellow wire on the fans is for, and what I should do with it?

I believe 3-wire fans have the extra wire to report RPM numbers to the motherboard bios and to adjust speed of fan.

I believe 3-wire fans have the extra wire to report RPM numbers to the motherboard bios and to adjust speed of fan.
Almost. The 3rd wire pulses once per revolution to allow the motherboard's management chip to monitor fan speed. It's only an output - it can't actually change the speed of the fan. That's done by PWM.

Got a problem. I tried hooking up the stripped wires from the AC adapter to the fan, it didn't work. I tried the wires hooked up to the opposite wires, didn't work. I touched the fan wires to a 9v battery, it worked.

Wtf is going on here? Should I try a DC adapter?

Ok, answered my own question. I found a DC adapter, hooked up the wires and it worked.

Now I'm out $18 bucks for the fucking AC adapter :mad:

and need to buy a new DC adapter :mad:

The dc adapter I have now is .3A, and I'm gonna be using 3 .1A fans. Would this work?? Or are there any dangers being right on the amperage rating?

Ok, answered my own question. I found a DC adapter, hooked up the wires and it worked.

Now I'm out $18 bucks for the fucking AC adapter :mad:

and need to buy a new DC adapter :mad:

The dc adapter I have now is .3A, and I'm gonna be using 3 .1A fans. Would this work?? Or are there any dangers being right on the amperage rating?

oshit, just found this out the other day too when I accidentally used an rectified wall wart. Killed my fan :(

oshit, just found this out the other day too when I accidentally used an rectified wall wart. Killed my fan :(

Are you sure it killed your fan and you aren't just connecting the wires to the wrong terminals. My fan still works just fine, and I noticed that my fan won't work unless the wires are hooked up to the proper polarities (i.e. ++, --).

Ok, so as it turns out I did have a DC adapter in the first place. It just doesn't work. I bought a new one and it works fine touching the wires together.

Now I'm scared to solder the new adapter because I have a hunch that the soldering is what broke the old one. Is it possible for the heat from the soldering iron to break the adapter??

*Update*

I finished the job with the new adapter and it all works fine. I guess the first adapter I bought was just defective, I wish I had tried it out before cutting the wires and soldering it.

The dc adapter I have now is .3A, and I'm gonna be using 3 .1A fans. Would this work?? Or are there any dangers being right on the amperage rating?


Are you fucking kidding me dude? If it's rated to handle .3 amps, I'm pretty sure drawing .3 amps isn't going to hurt it...


Stop being stupid and use your head next time before you post.

Are you sure it killed your fan and you aren't just connecting the wires to the wrong terminals. My fan still works just fine, and I noticed that my fan won't work unless the wires are hooked up to the proper polarities (i.e. ++, --).

Yeah, it's dead. And I meant to say I used an UNrectified transformer.

It smoked :(