Authors : Pawan Bajpai

Volume/Issue : Volume 11 - 2026, Issue 9 - September

Google Scholar : https://tinyurl.com/2kv779rw

DOI : https://doi.org/10.38124/ijisrt/26sep347

Note : A published paper may take 4-5 working days from the publication date to appear in PlumX Metrics, Semantic Scholar, and ResearchGate.

Abstract : Earthing and protection in a photovoltaic power system is a plant-wide network, not a set of isolated earth pits. This paper sets out a single design method that applies to both ground-mounted and rooftop installations, and identifies where the two diverge. The method proceeds from measurement of the earth termination environment, through equipotential bonding architecture, conductor sizing against the thermal limit, verification of touch and step voltage, lightning risk assessment and surge protective device coordination, connection technology, protection coordination, and commissioning verification. For ground-mounted plants the earth termination is a purpose-built buried grid sized from measured soil resistivity across the site. For rooftop plants a soil measurement is generally unavailable to the PV designer; the array is bonded into the existing earth termination and lightning protection system of the host building, which shifts the design problem from resistance reduction to equipotential bonding, separation distance and coordination with structures the PV contractor does not own. Comparison tables are given for each design step, together with a worked conductor sizing example for both system types and a commissioning checklist differentiated by installation type. The worked example shows that the thermal limit governs only the ground-mounted main grid; elsewhere the tabulated minimum of the wiring rules, or the minimum required of a lightning protection bonding conductor, governs instead.

Keywords : PV Earthing; Equipotential Bonding; Touch and Step Voltage; Earth Grid; Lightning Protection System; Surge Protective Device; Rooftop PV; Ground-Mounted PV; Commissioning Verification.

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