Rolling Sphere Method Calculator [hot] Direct

The sphere’s radius is not arbitrary. It is derived from the formula, which relates to the peak lightning current. The most common standard (IEC 62305 and NFPA 780) defines protection levels (I to IV) with corresponding sphere radii:

[ d \leq \sqrtr^2 - (h - r)^2 - \sqrtr^2 - (H - r)^2 ] rolling sphere method calculator

: The tool instantly shows that at 19 m separation, the top 0.8 m of the arrester remains exposed. You then add a second mast, and the overlapping spheres create full protection up to 28 m separation. The sphere’s radius is not arbitrary

: How far can the arrester be from the mast? You then add a second mast, and the

: Never trust manual approximations for critical infrastructure. Run the rolling sphere simulation, verify the red zones, and then build with confidence. About the author: This article is based on principles from IEC 62305 and IEEE 998. Always consult local codes and a licensed engineer for final designs.

Introduction