Reduce Fan Speed With Resistor

If the motor draws constant current then the resistor will drop a constant voltage and the motor will run at a fixed lower speed.

Reduce fan speed with resistor.

3 pin male to female. Quite practical and useful. Use the 3 pin cable to connect the power supply to your cooling fan it will reduce the speed of the fan and cut the noise output dramatically. Designed with a resistor on the cable.

I have a 5v usb fan and i want to reduce the speed. Quite practical and useful. The only thing that has to be done is to connect a resistor in series with the power supply of the fan. Ecm motors typically offer all the same speed adjustments as psc s with the added ability to reduce speed in smaller increments from the low medium low medium high and high settings.

3 pin male to female resistance. Designed with a resistor on the cable. Use the 3 pin cable to connect the power supply to your cooling fan it will reduce the speed of the fan and cut the noise output dramatically. Among all circuits i have make this is the simplest one.

In our psc example we would likely have had to slow the fan speed by 7 15 to give us the ability to get much closer to our target of 350 cfm ton. This voltage drop will be subtracted from the overall voltage on the fan and therefore the voltage across the fan will be reduced. It uses a resistor to generate voltage drop and thus reduce the speed of a dc motor like the pc fan. So to achieve a voltage drop of 5v we would need a resistor with value of 42 ohms and capable of dissipating 0 6w of power.

This highlights one potential pitfall of this method you can t safely use 1 4w resistors for this unless you make up the target resistance using several smaller resistors of equal value in series.