This little 5-volt fan was intended for use in a PC (laptop or similar), but it has 3 wires coming out of it - black, red, and yellow. As there aren't any split 5v supplies in a PC I was wondering which wires to use.
Anyone know the answer?
David
This is VAGUELY car-related, as it's to do with a little fan I bought in Maplins to go into the case for my JAW AFR meter...
This little 5-volt fan was intended for use in a PC (laptop or similar), but it has 3 wires coming out of it - black, red, and yellow. As there
aren't any split 5v supplies in a PC I was wondering which wires to use.
Anyone know the answer?
David
Yellow 12v+
red 5v +
black 0v - or earth
Try the yellow and black across your battery in the right order or it will spin backwards.
I don't reckon that's right!!!
I reckon its
Red 12v
Yellow tacho
Black ground
You might have a speed sensor on the fan but normally black=gnd, yellow=+ve
http://www.pcguide.com/vb/archive/index.php/t-19457.html
There we go 
From the PC power supply its Yellow=12, Red=5v, Black=Gnd
but on the fan its Red/Black = Power/Gnd
If you ground the red it's 5 volt if you ground the black it's 12v according to that then?
[Edited on 18/5/08 by Peteff]
Not all PCs fans have the tacho function and when they don't it's the yellow wire that's missing.... QED
And not all PC fans are 12v, some are only 5v usually the ones which plug into the board not into the PSU.
quote:
Originally posted by BenB
I don't reckon that's right!!!
I reckon its
Red 12v
Yellow tacho
Black ground
The 5v ones I have are from an old pentium pro system so they probably don't exist any more. There's a site here telling how to run your fan as a 7v as well link
It is 5v, according to the label, at 80mA.
I've tried it across the red and black wires and it runs very nicely, so thanks to all.
I forgot to mention just how small this thing is - it doesn't shift a lot of air (understandably) but all I want it to do is to move air across a
voltage regulator heatsink.
It may be small but its still adds weight! 