Design, Implementation, and Empirical Validation of an IEC 62305-Compliant Lightning Protection System for Enhancing Infrastructure Resilience and Energy System Reliability

This research presents a comprehensive and detailed study of the design, implementation, and experimental validation of a Lightning Protection System (LPS) for a multi-story commercial building in Isfahan, Iran, in full compliance with the international standard IEC 62305. The study bridges practical engineering execution, covering all stages from the initial risk assessment to system commissioning and verification. Using advanced software tools based on IEC 62305-2, the authors conducted a formal risk analysis that identified the need for a Class IV LPS and Class III–IV Surge Protective Devices (SPDs). The LPS was designed as a passive protection scheme consisting of Franklin-type air terminals, multiple down conductors, and a comprehensive grounding system with equipotential bonding throughout the structure. The installation phase involved the application of different electrode configurations, including conventional ground rods, parallel rods, and the use of the building’s steel foundation as part of the grounding network. Post-installation validation employed standard testing methods, including the two-point dead-earth method and the 62 percent fall-of-potential method in accordance with IEEE 81 and BS 7430, to measure grounding resistance. Equipotential bonding continuity was verified using a calibrated METREL MI3250 instrument with 10 A current injection. The measurements revealed significant variations in resistance, ranging from more than 21 ohms for non-optimized single electrodes to 1.29 ohms when utilizing the tower foundation, demonstrating the critical impact of electrode integration and soil conditions. Equipotential bonding achieved milliohm-level continuity throughout the structure, confirming electrical integrity. This work provides not only an engineering blueprint but also a rare real-world validation of IEC 62305 implementation. By presenting field data applicable to simulation models, regulatory compliance, and future LPS design, the study fills an important gap in the technical literature and contributes to enhanced safety in energy-sensitive environments.