Can i add a resistor to fan power cable to reduce speed???

[mackstann]

another guy's post jogged my memory to ask this...

basically, i have an asus A7V and a superorb (sucks, i know...), and i wanted to try reducing the fan speed for the top fan on the superorb (since it has less effect than bottom fan) by putting a resistor in-line on the power wire to the fan (actually, maybe a pot would be more fun...like steppin on the gas, but with a fan!)

so, would i damage anything doing this?

 

[Rafael]

Yeah, its possible. You just need to calculate, and check what kind resistor you need to reduce the speed to ur desired speed.
Dont think it would damage anything.

Raf

 

[etech]

It will work, the only thing to watch besides the value is the wattage that the resistor or pot. must disapate.

P=IE

Watts = Current * Voltage

Calculate how much current your fan is drawing at 12 volts. The wattage should be on the fan label. Use that current times the voltage you want to drop across the resistor(it will be higher but that adds in your safety margin).

Too small a resistor will get very hot.

 

[4824guy]

you can even wire in a pot. to controll the rate of the fan.

 

[NuovoTech]

Yep, been using Radio Shack(271-265b) 25ohm, 3watt rheostats as you state 4 some time, works fine! Add inline to red power wire, rpm senser will still work...