An electrical earthing refers to the transfer of the instant discharge of an electrical energy straightaway to the earth through low resistance wire.
Earthing is carried out through the connection of non-current equipment to the ground. It is done to ensure safety.
Proper earthing installation can save you from any kind of electric shocks by transferring the fault current flow to the ground.
Many factors play a vital role in an earthing installation and it is always important to take all of them into consideration before finally deciding on a particular type of earthing installation & the circuits that are required for this work.
Some of the factors that affect an earthing installation are as follows:-
- Soil Condition
The condition of soil plays a key role in determining the efficacy of earthing. The resistance of earth, the salt and the moisture level of the soil tells earthing specialists as to how an earthing is made. For example, earthing in rocky soil is different from earthing in wet soil.
- Soil Resistivity
Soil resistivity is another factor that affects earthing installations. Different conditions of soil provide different kinds of soil resistivity. A majority of soil conditions are not adaptable to earthing installations. Experts measure soil resistivity in ohm-cm or ohm-meters. Soil having low resistivity is extremely corrosive. The resistivity value of soil will be extremely high if the soil is dry and if the soil has high resistivity, then the electrode’s earth resistance will be high.
- Dissolved Salts
Pure water is considered a bad conductor of electricity. Soil resistivity depends on water resistivity which then depends on the quantity as well as the nature of salts that are dissolved in it.
- Moisture in Soil
Moisture existed in the soil is tested by considering the amount of water contained by the soil & its water resistivity. Hence, it is very important to provide water in the earth and around it for maintaining the moisture in a dry climate.
- Location of Earth Pit
The location where the earthing is done is also of great value. In case the earthing is to be done for a sloping landscape, hilly areas & rocky areas, water runs off. However, in a dry climate, the water table decreases extremely fast. In these situations, the backfill compound is not workable for moisture as the surrounding the pit would become dry.
- Physical Composition
A variety of soil composition offers different resistivity. Clay soil has a 4-150 ohm-meter resistivity range, whereas the range for gravel or rocky soils may be above than 1000 ohm-meter.
- Climate Condition
The climate condition also affects the earthing process. When the moisture in the soil increases or decreases, the soil is increased or decreased respectively. So, in a dry climate, the resistivity is high & in monsoons, the resistivity becomes low.