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Research in the field of electrical grounding operations mainly focuses on the relationship between the efficacy of the grounding, the characteristics of the soil (resistivity, moisture content etc.), the construction materials used and the quantity, form and location of the grounding electrodes, etc. Currently in new construction or reconstruction projects, grounding works are usually carried out after the excavation for the building(s) foundations, making them the first onsite electrical work. The installation is a sequential process of: excavation, burial of grounding electrodes, wire connection, testing and then maintenance, etc. Electrodes, multiple metal grounding poles (or copper plates) along with metal wires form a ionic grounding grid, The system can be divided into lightning protection and grounding provision in the forms of: weak current, equipment, static electricity, etc. Naturally if there are multiple equipment systems or multiple grounding systems then a ground bus will be used to join the grounding network. The connecting wire’s distance from the ground bus to the grounding network is the reference basis of the ground bus potential. If the measured value of grounding resistance exceeds the design specifcation then electrodes wired in parallel are used to reduce the resistance. Most commonly metal objects are used as wires for grounding, because metal has free electrons and is a good conductor of heat and electricity, they, can quickly release fault induced currents and accumulated charges, into the soil through metal grounding systems forming ground loop circuits. If a human touches the charged leakage equipment. The grounding system is set up to prevent the staff from accidentally touching the leakage equipment and causing damage due to the induced current. When the building is complete the grounding system’s , resistance value will have increased due to rust caused by long-term exposure of the grounding pole, so the grounding system should be tested and maintained regularly.
Keywords: Grounding, Soil, Wire
*Advisor
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