Fan speed controllers
Fan control is the management of the rotational speed of an electric fan. In computers, various types of computer fans are used to provide adequate cooling, and different fan control mechanisms balance their cooling capacities and the noise levels they generate.
Thermal controller fans are used by sensing the temperature of computing devices and increasing or decreasing the speed of fan control to regulate the temperature inside the computer to keep devices from failing from overheating.
In thermostatic fan control the fan is either on or off. The temperature inside the chassis is checked and if an outside of temperature range is give the required output detected fans are set to their maximum fan speed. If the temperature drops to below the threshold set by the controller the fan turns off. This type of control method reduces noise issues and power requirements during periods of low usage. When the system is operating at capacity the fan noise can become a problem again.
Time switch controllers can also be used to control the speed of the fan via settings which control the fan speed and duration of running time.
Pulse-width modulation, also known as PMW, is also a common method of controlling computer fans. This gives the fan controller the ability to adjust the rotation speed on the fly without changing the input voltage to the cooling fan.