Specification required for Earthing

1)      Earthing electrode should be placed at least one and half meter  away from the building
2)      Earth wire should be same material with earth electrode
3)      The minimum sectional area of earth wire should be greater than 0.02 sq. inch and less than 0.1 sq. inch
4)      The size of earth conductor should not be less than half of the section of a line conductor
5)      The earth electrode should be taken as GI pipe with minimum diameter of 12 mm and at least 32 cm length
6)      Coal and salt mixture with loose soil should be filled around the earth electrode
7)      All the earth wire run along with the sub-circuits should be terminated hooked firmly at the main board
8)      The earth resistance should be low enough to flow of current sufficient to operate the protective relays and blow fuses


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