Nothing can be compromised when it comes to safety. Chemical earthing systems do provide enhanced protection from lightning and electrical surges, however it is necessary to keep a check on the ground earthing system values. The resistance offered by the earth electrode to the flow of current into the ground is known as the earth resistance or resistance to earth. This resistance value is commonly referred to as earthing value.
The most acceptable earthing value is five ohms.
However there are various factors governing the earthing value.
The factors that earthing values depend on are:
Weather: The weather conditions keep fluctuating near the end of the seasons. Checking earthing values in odd intervals ensures that the worst time of weather fluctuations and conditions do not hamper with the earthing values
Moisture: The soil can be moist due to excessive rainfall, water spillage or simply due to overwatering in places like farms and meadows. The moisture is retained by the soil for some period of time. This automatically makes the soil more conductive. If the chemical earthing system is tested in such moist soil, the system might pass off as acceptable due to the low resistance of the soil might. In such cases, the system might not be appropriate in less moist and dry conditions.
Physical composition of the soil: The physical properties of the soil vary from region to region. The chemical earthing values need to be differentiated depending on the physical composition of the soil where the system needs to be installed Factors like dissolved salts, grain size and distribution, seasonal variation, current magnitude need to be checked in order to determine what earthing value is the most suitable for chemical earthing system.
Resistivity of soil: Resistivity is the measure of resistance over distance. Soil resistivity depends on the temperature of the soil. The resistivity of the soil may vary from 1 to 1000 ohm-m depending on the nature of the soil. Soluble salts also affect the resistivity. It needs to be identified properly to decide the earthing value of that particular soil.
These were the four most important factors that govern earth resistance or earthing value for chemical and conventional earthing systems alike. In chemical earthing systems like the ones that Atharva Infrastructures offers, the systems can be checked in every five, seven or at the most nine months. It is necessary to keep a check on the earthing value of the soil so as to avoid any disasters due to lightning or electrical surges.