The speed of the fans are controlled by speed regulators.
The speed regulator is wound with eureka wire and consists of a number of resistance steps in series and is connected to the fan motor in series of the supply.
The applied voltage to the motor is varied by changing these resistances, in steps and fan works on the speed which we require.
Now a days, electric speed regulators are used.
Thyristor controlled circuit is used to control the speed of fan.
The speed can be controlled smoothly from zero to maximum using electric speed regulators.
