A Guide to Earthing: Types, Merits, and Procedure
At the heart of every electrical installation is the desire to protect people and property from electrical hazards. One of the ways to achieve this is through earthing. Earthing is the process of connecting electrical conductors to the earth. This creates a safe path for electrical currents to flow and prevents shocks, fires, and other electrical hazards. In this article, we will explore different types of earthing, their merits, and the procedures involved.
Types of Earthing
There are three main types of earthing, namely:
- Plate Earthing: This is the most commonly used type of earthing. It involves burying a copper plate in the ground and connecting it to the electrical installation using a conductor.
- Rod Earthing: This involves burying a metal rod in the ground and connecting it to the electrical installation using a conductor. Rod earthing is more effective than plate earthing in areas with high soil resistance.
- Pipe Earthing: This involves using a metal pipe instead of a plate or a rod. The pipe is buried vertically in the ground and connected to the electrical installation using a conductor.
Merits of Earthing
Earthing has several benefits, including:
- Protection from Electrical Hazards: Earthing provides a safe path for electrical currents to flow. This prevents electrical shocks, fires, and other electrical hazards.
- Protection of Equipment: Earthing protects electrical equipment from damage caused by lightning strikes and power surges.
- Improved Power Quality: Earthing reduces electrical noise and interference, resulting in improved power quality.
Earthing Procedure
The earthing procedure involves the following steps:
- Soil Testing: Before earthing can be done, the soil resistivity must be determined. This is done by conducting a soil test.
- Earthing Material Selection: The earthing material is selected based on the soil resistivity and the electrical load.
- Earthing Installation: The earthing material is installed by digging a pit and burying the earthing material in the ground. The earthing material is connected to the electrical installation using a conductor.
- Earthing Resistance Testing: After installation, the earthing resistance must be tested to ensure that it meets the required standards.
Conclusion
Earthing is an essential aspect of electrical installations. It protects people and property from electrical hazards and improves power quality. There are different types of earthing, including plate earthing, rod earthing, and pipe earthing. Each type has its merits and is selected based on the soil resistivity and the electrical load. The earthing procedure involves soil testing, earthing material selection, earthing installation, and earthing resistance testing.