Earthing System Design for Electrical Installations of Building Construction and Laboratory Equipments

This paper presents the design of earthing system for electrical installations for domestic, commercial and laboratories, etc. and calculation of its technical parameters. Successful operation of entire building power system depends on efficient and satisfactory performance of well-designed earthing system. Lack of safe and effective earthing system can result in non-operation of control and protective devices. (Earthing/ Proper grounding) of system design deserves considerable attention for all the building power system. Earthing system has to be safe as it is directly concerned with safety of persons living in building and working within the building power system. Main concern of this work is designing safe and cost effective earthing system for building power system situated at such locations where soil of the site is non-uniform. Initially significance of earthing is explained & methodology for design of building power system earthing system. Earthing is very important to achieve instruments and personnel protection. Operation of any electrical and electronics instrument or appliances directly affected by value of earthing. Standard formulas are used in design of earthing system to get required values such as touch and step voltage criteria for safety, earth resistance, minimum conductor size and electrode size and resistivity of soil.