Earth Fault Causes, Effects, Example, Explanation
The connection of the noncurrent carrying part of an Electrical Equipment to Earth is called Earthing. During installation, most of the electrical equipment and the machine's metallic body are connected to the earth to reduce the chances of electrical shock which is called body earthing. Electrical Earthing is mainly done for safety purposes.
The earthing system provides a very low resistance, when accidentally any live or phase wire touches to the body of the electrical equipment, fault current will be grounded or discharged through the earthing conductor and protect the human from electrical shock.
Causes of Earth Fault
Earthing is the connection of the metallic body of any electrical equipment, device or machine to the earth. So if accidentally earth conductor is damaged, then that device is not connected to the earth so there is no safety for electrical shock.
Mainly the earning fault indicates the fault between the line and the earth.
The main cause of earth fault in an overhead transmission or distribution line is the failure of the insulator. The insulator is used in an overhead transmission line to provide the insulation between the live conductor and the metallic tower which is already connected to the earth. So if insulation becomes fails, the fault current will flow through the live conductor and the metallic tower to the earth.
Line to Earth Fault
As the metallic body of any electrical equipment or device is connected to the earth. So if the live or phase wire touches to the body of the electrical equipment then a huge current will flow through the phase and earth conductor which is known as Line to Earth Fault.
When the line-to-earth fault occurs, a huge amount of current flows so there will be a large voltage drop.
Effects of Earth Faults
When Earth faults occur a huge amount of current flows through the phase and earthing conductor and a large voltage drop occurs. So this will affect the other loads and it may cause the burning of the phase or line conductor.
Earth fault causes huge sparking, Heat, fire, etc.
Earth Fault Protection
Earth Leakage Circuit Breaker or ELCB is used to give protection against Earth Faults. It is a voltage-operated device. When an earth fault occurs a voltage appears across it and it trips and disconnects the main power supply.
In the below figure, you can understand the working principle of an ELCB easily.
Here, you can see the Relay of the ELCB is connected between the metallic body of the motor and the earth or ground. In the normal conditions, the circuit breaker is closed condition so the motor gets a power supply. When an earth fault occurs, the fault current will flow through the earthing wire and a voltage will appear across the relay coil and the relay will trip the circuit breaker. Thus the motor will disconnect from the main power supply during the Earth fault.
Thank you for visiting the website. keep visiting for more updates.
Earth Fault Causes, Effects, Example, Explanation
Reviewed by Author
on
March 11, 2020
Rating:
Reviewed by Author
on
March 11, 2020
Rating:
