Fan Capacitor is a power device connected in series with the auxiliary winding of a fan motor to create a rotatory magnetic field and set the fan in motion.
For example, electric fans use a single phase motor to blow the air, but they are not self-starting motors because the torques produced by the windings cancel out. Hence, they require an external force to align the cancelling torques into net-non-zero torque and put the fan in motion.
However, since we expect the fan to work with just the push of a button, this is where the role of the capacitor comes into play. By bringing the alternating current in the auxiliary winding 90 degrees forward with respect to the main winding, capacitors create a net-non-zero torque that allows the fan to spin without the help of any external force.
We have 3 types of fan capacitors:
1. Fan Capacitor
2. Oil-Filled Fan Capacitor
3. Super Fan Capacitor