What is the Role of Capacitor in a Ceiling Fan?

What is a Capacitor?

• capacitor is two terminals electrical devices that store enegy if the form of electric charge. It comes with two electrical conductors that part with some distance. The space between conductors is filled with vacuum or with insulating materials called dielectric.

Introduction to Ceiling Fan

The ceiling fan is used in our living rooms, bedrooms kitchen. has size of blade span about 36” (900mm), 48” (1200mm), and 52” (1300mm). The main parts of ceiling fans are listed here.

• Stator:  Stator is the static part of the fan motor that has two windings. Main windings and auxiliary winding. The shaft holes the stator also called rod pipe.
• Rotor: it is the rotating part of the fan and connected wings to the rotor. In the form of the motor, the rotor is like a squirrel cage rotor with bars of copper or aluminum
• Capacitor: The ceiling fan has a single-phase motor, that is not the self-starting motor. To make the motor self self-starting capacitor is used in series with auxiliary winding.
• Regulator:It is used to control the speed of the fan.

Importance of Capacitor in Ceiling Fan

The capacitor is the main device for the working of the cealing fan motor. It helps to offer the required starting torque to the fan motor and make sure that the fan starts fast and smoothly. The importance of capacitors for fans is explained here.

1. The capacitor helps the fan motor to control the inertia of fan blades and causes them to move helping the fan to start fast and smoothly. If there is no capacitor fan can face difficulty starting or also stall causing damage.
2. The capacitor protects the fan motor and other parts of the fan from getting damaged. The fan faces difficulty starting or stalls can damage the motor, bearing, etc. increasing the cost of repairing.
3. it increases the fan motor efficiency. The fan starts fast and smoothly easily uses less energy produces less heat increases the life of the motor and minimizes energy costs.
4. The capacitor also provides reliable operation for fans.

 Different Types of Capacitors

• There are different types of capacitors, such as electrolytic,  tantalum, ceramic, and film varieties. Each type of capacitor has its features and sues based on functions. The electrolytic capacitor is the comonly used type of capacitor in-ceiling fans.

Role of Capacitor in a Ceiling Fan

In ceiling fan capacitor is used to offer the required starting torque to the fan motor. The capacitor is an important component that stores and releases electrical energy.

It operates by storing the charge of electrical energy on two metallic plates, known as electrodes that are separated through the insulation material. Energy stored in capacitors is measured by capacitance that is measured in microfarads (μF).

When the fan is on, the motor at the start needs more energy to start rotating, when it running, it needs less energy for running. To offer this initial energy boost capacitor releases stored electrical energy to the motor, offering the required torque. In a result, fan motor starts smoothly.

The main role of a capacitor in a fan is to help the motor control the inertia of the fan blades and get motion. Without the capacitor, fan does not start and can stall resulting the damage.

It is good to note that when the fan is running, the capacitor is not needed and the fan motor runs on the power given through the AC line. The capacitor only needed to provide initial starting torque and it disconnected when fan was running

Faulty Capacitor Symptoms

If the ceiling fan capacitor is damaged then the fan will not start or start rotating at a low speed. Damaged capacitors cannot be fixed or repaired. The only thing is to replace the capacitor.

The capacitance of the ceiling fan is about two to 70 microfarad. So check the manual details of a fan before installing capacitors with a fan.

How to Replace a Faulty Capacitor?

• First of all off the power supply from the main breaker in the home db board.
• Remove the faulty capacitor by cutting the wires connected to a faulty capacitor.
• Replace the capacitor by connecting the Red wire to the first terminal of the capacitor and connecting the blue wire with 2nd terminal of the capacitor.
• Now connect red and blue wire place the wire nut and electric tap and insert wire connectors.
• Now connect black from ceiling fan to 2nd slot of wire connectors.
• Connect live and neutral with the power supply. On the main break to test the ceiling fan..

Capacitor value for ceiling fan

• Normally ceiling fan capacitors have a range of 1.5 to 10 μF, with voltae features of 370 V or 440 V. If there is wrong capacitance value capacitors used can cause an uneven magnetic field around the rotor.

Advantages of Capacitor in a Ceiling Fan

Ceiling fan capacitors’ main advantages are here

• Energy efficiency: The use of a capacitor to control the speed of the fan casues less energy use and decreases the power expenses
• Longevity:  By proving the required starting value of torque and speed of the fan capacitor protects the fan motor and increases the operating life of the fan

 Capacitor Wiring Diagram for Ceiling Fans

wiring diagram for the ceiling fan capacitor:

• Make the connection of the red wire with the switch of the fan.
• Motor connected with black wire.
• The blue wire is connected to the fan light kit.
• There must be a neutral wire connected with a white wire.

Ceiling Fan Motor Circuit Diagram

Normally ceiling fan motors are split-phase single-phase AC motors. There are two windings in the ceiling fan starting windings and running windings. Starting winding is called auxiliary windings and running winding is called main windings.

In the above circuit diagrams solie phase induction motor in the ceiling fan is connected with a capacitor in series with starting winding. So

A ceiling Fan without a Capacitor

• In some conditions if there is no capacitor connected to the ceiling fan. So in this configuration starting and running windgs are connected in parallel to single phase supply.
• In this condition current flows through winding inductors, it will generate a pulsating magnetic field, then a rotating magnetic field that is used for torque and rotation.
• As a result of a single-phase supply there is one revolving flux that rotates clockwise and then in an anticlockwise direction at the same time.
• The direction of motor rotation varies after each half cycle which casues the rotor to rotate in a clockwise and antilock direction.
• On the basis of double field revolving theory, both torques cancel each other after half a cycle. The resulting rotating magnetic field will be zero, or zero starting torque.
• So ceiling fans and single-phase induction motors are not self-starting motors.

FAQs:

What happens when the capacitor goes bad in a ceiling fan?

The capacitor provides starting torque to the fan and sustains constant torque as the fan works. When the ceiling fan capacitor is affected torque is affected, which casues the problems such as slow fan speeds or the fan not starting at all.

How long do capacitors last in ceiling fans?

Normally ceiling fans work for  5 to 12 years.

Can a ceiling fan work without a capacitor?

Without a fan capacitor the magnetic flux shifts completely for every current cycle. it will produce a magnetic field in the fan and fan will not move. This is the reason for using a fan capacitor.

Can I use a capacitor with a higher voltage rating in a ceiling fan?

Always safely connect the capacitor for a voltage less thatn the rated voltage, but not high voltage. It will affect the capacitors

How do I know which capacitor to buy for my ceiling fan?

The capacitor value for the ceiling fan based on motor featues and requried speed. Normally capcitor with value 1.5 to 3 uF is best to use for ceiling fan.