Rolling Sphere | Method Calculator

For decades, the protection of structures against direct lightning strikes has relied on a few key geometric models. Among them, the stands out as the most intuitive and physically accurate representation of how lightning intercepts a structure. Unlike the older "cone of protection" method, RSM accounts for the actual striking distance of lightning, making it indispensable for protecting complex or sensitive facilities like substations, data centers, petrochemical plants, and tall buildings.

: Using the formula, the maximum distance is ≈ 18.7 m. rolling sphere method calculator

| Protection Level | Peak Current (kA) | Rolling Sphere Radius (r) | | :--- | :--- | :--- | | Level I (Highest) | 3 kA | 20 m (66 ft) | | Level II | 5 kA | 30 m (98 ft) | | Level III | 10 kA | 45 m (148 ft) | | Level IV (Lowest) | 16 kA | 60 m (197 ft) | For decades, the protection of structures against direct