This paper explains the inefficiency of Surge Arresters in protecting distribution transformers during lightning, due to the wrong installation of surge arrestors. Transformers with a primary voltage up to 33kV are considered in this paper. CEA Regulations (Measures relating to Safety and Electric Supply) on protection against lightning is explained, then the typical installation practices are studied and correct installation as per IS 15086: Part 5: 2020 and IEEE 142 are explained. The conclusion is drawn from the effectiveness of the regulation and recommendations are given.
