Plate earthing, also known as earth plate or grounding plate, is a common method of creating an electrical connection between an electrical system and the ground. It involves burying a metal plate, typically made of copper or galvanized steel, in the earth to establish a low-resistance path for electrical currents.
Plate Earthing is consist of following points:
Grounding Plate:
A grounding plate is a metal plate that serves as the grounding electrode. It usually buried vertically or horizontally in the ground, depending on the specific requirements and soil conditions. Copper or galvanized steel plates commonly used due to their corrosion resistance and conductivity.
Size and Configuration:
The size and configuration of the grounding plate depend on factors as soil resistivity, fault current levels. Larger plates provide a larger surface area for better conductivity and reduced grounding resistance. The shape of the plate can vary, including square, rectangular, or circular designs.
Depth of Burial:
The grounding plate buried at a specific depth in the ground, typically ranging from 1.5 to 3 meters . The depth determined by soil conditions and local regulations to ensure adequate electrical contact with the surrounding soil.
Backfill Material:
After burying the grounding plate, it is important to backfill the surrounding area with a conductive material, such as a mixture of charcoal, salt, and bentonite. This backfill material enhances the conductivity of the soil and helps maintain a low-resistance connection between the plate and the earth.
Connection to Electrical System:
The grounding plate connected to the electrical system’s grounding conductor, often using a copper conductor or copper strip. This conductor carries fault currents or leakage currents to the grounding plate, providing a safe path to the ground and protecting against electrical hazards.
Plate earthing commonly used in residential, commercial, and industrial electrical installations. It provides an effective and reliable grounding solution to ensure the safety of electrical systems, protect against electrical faults, and dissipate transient overvoltages.
While designing and implementing a plate earthing system, it is crucial to follow applicable electrical codes, standards, and local regulations.
Following are the applications of plate earthing:
Power Systems :
- Plate earthing commonly used for substations, transmission towers, pole transformers, and other power system equipment. It provides a low resistance path to ground to safely dissipate fault currents.
Electrical Equipment :
- Plate earthing is used for grounding electrical equipment like motors, generators, switchgears, UPS systems, panel boards. Protects equipment and personnel in case of faults.
Telecom Towers :
- Plate earthing provides an effective earthing system for telecom towers, antenna masts to protect against lightning strikes and electrical surges.
Electronic Systems :
- Sensitive electronic systems like computers, servers, and data centers use plate earthing to maintain a zero potential earth reference. Helps avoid disturbances.
Residential Buildings :
- Plate earthing is an appropriate earthing method for residential complexes and apartments to earth the electrical system.
Lightning Protection :
- Lightning arrestors and lightning conductors are earthed using plate earthing as it can disperse high lightning current into the ground.
Metal Structures :
- Metal structures like tanks, pipeline, enclosures, and ventilation systems are earthed with plate earthing to prevent build up of static charges.
Hazardous Areas :
- Equipment in hazardous areas where flammable gases or combustible dusts are present require low resistance plate earthing for safety.
Temporary Grounding :
- Portable plate earthing is used for temporary grounding of equipment during maintenance, repairs or emergencies.