3-pin potentiometer to 2-wire fan

Wavey

Morning all,

I want to install a couple of variable resistors in my pc to control the fan speeds.

The restistors i have are 3-pin.

How do i wire this to the fan power lead?

any advice appreciated

Cheers
Wavey

Sherifu

all you need to know is here: http://en.wikipedia.org/wiki/Potentiometer

Basically the middle terminal is usually the wiper.
The resistance between it and either outside terminal
will be proportional to the turning of the axle.

Capt'n Midnight

resistors "burn" off the extra power

most pots are low power so may not handle the heat.

many 12 volt fans will also run on 6v so you wire two in series - this would give less than half the air flow but a lot quieter.


you could wire up a 7805 - this will give up to an amp while only using a few miliamps through the pot via the ground pin
one pin to +ve
one to fan
middle pin to the pot

Wavey

cheers guys,

whats a 7805? a chip?

Fmicrochip

The 7805 is a voltage regulator to give you a 5V output. I'm afraid this also has 3 pins...