What are the 2 major types of earthing

In electrical engineering, earthing refers to connecting electrical systems and equipment to the ground. This connection serves two important purposes: providing a reference potential for the system and protecting against electrical faults. There are different types of earthing methods available, but in this article, we will focus on the two major types of earthing - electrode earthing and plate earthing.

Electrode Earthing:

Electrode earthing, also known as rod earthing, is one of the most commonly used methods of earthing. It involves installing metal rods, typically made of copper or galvanized steel, deep into the ground. These rods act as electrodes that establish a direct connection between the electrical system and the earth.

During installation, the rods are driven vertically into the ground, ensuring good contact with the soil. The depth of the rods depends on factors such as soil resistivity and fault current levels. Generally, rods should be buried at least 2 meters deep to ensure sufficient grounding.

Once the rods are installed, they are connected to the electrical system using conductors. The connection is made at the main earthing point, which is usually near the electrical distribution panel or the power source. Any fault currents generated within the system will flow through the rods and safely dissipate into the ground, preventing damage to the electrical equipment and reducing the risk of electric shock.

Plate Earthing:

Plate earthing, also called strip earthing, is another widely used method of earthing. Instead of metal rods, this method relies on metal plates or strips buried horizontally in the ground. The plates are made of materials like copper or galvanized iron and typically have larger surface areas compared to rods.

Similar to rod earthing, plate earthing requires good contact between the plates and the soil. To achieve this, the plates are buried at a depth of around 3 meters below the ground surface. It is important to choose an appropriate size and shape for the plates based on factors such as soil resistivity and fault current levels.

The electrical system is connected to the plates using conductors just like in electrode earthing. The connection is made at the main earthing point, ensuring a low-resistance path for fault currents to flow safely into the ground. Plate earthing is commonly used in areas with high soil resistivity, as the larger surface area of the plates helps to reduce the overall resistance of the system.

Conclusion:

Earthing plays a crucial role in electrical systems by providing a safe path for fault currents to dissipate. Electrode earthing and plate earthing are two major types of earthing methods, each with its own advantages and applications. Whether it be rod earthing or plate earthing, choosing the right type of earthing system depends on various factors such as soil resistivity, fault current levels, and local regulations.

Proper installation and maintenance of the earthing system are essential to ensure its effectiveness. Regular testing and inspections should be carried out to ensure that the earth electrodes and connections are in good condition. By implementing proper earthing practices, electrical systems can operate reliably and safely, minimizing the risks associated with electrical faults.