External Lightning Protection System Lecture 1: Basics of Air Termination System 

This lecture provides a basic understanding of the air termination system as per IEC 62305-3(external LPS design). It provides an overview of the rolling sphere method (RSM) and protection angle method. Furthermore, it explains how the protection angle method is a mathematical simplification of RSM and provides what angles are to be considered for different heights of rods and class of LPS. It explains that 45 degrees of protection angle that we consider is not in accordance with IEC 62305-3.