The main reason why electric cooling fans
An electric cooling fan of a motor Single Phase Industrial Fan Motor-YSF71-4-0.75KW vehicle is made up of (1) the fan motor and (2) the circuit. The circuit consists of the fan switch and the relay. The function of the switch is to send power to the relay and to sense the internal temperature of the engine and switch on the cooling, if there are signs of heating.
Generally the electric cooling fan is mounted behind the radiator. However in some vehicles, there may be large and wide radiators. In such cases, there may be two fans, or there may be a separate fan purely for the air conditioning condenser.
Mostly the fans are switched on when there is heating inside. This helps to cool the engine. There is a separate engine temperature switch or an engine coolant sensor which is used to monitor the engine temperature. When the engine is first started, the fan is not started until it reaches the normal operating temperature which is between 195 to 215 degrees. Then the fan will cycle on and off as needed to maintain the temperature. So if the engine is at normal temperature, the fan will run in a low or idle speed.
The main reason why electric cooling fans are now used in many vehicles in place of the traditional belt driven mechanical fan is to improve the fuel consumption and reduce the noise of the fan, especially when the vehicle is running at high speed. A fan that is driven by a belt can consume more than 12 horsepower or even more depending of course of the speed of the engine and the load.
