Power transformers. Part 3 : Insulation levels and dielectric tests

This technical document serves as an amendment to the foundational set of requirements governing power transformers. Specifically, it addresses the third section, which focuses on insulation levels and dielectric performance tests. The content establishes essential guidelines for determining the withstand capabilities of transformer insulation systems under various electrical stress conditions. It outlines procedures for conducting critical tests to ensure the device can maintain integrity during operation and transient events. The amendment introduces refinements to previously established test methods, aiming to enhance the precision and reliability of assessment protocols. By defining specific voltage parameters and test sequences, it supports the verification of safety margins for high-voltage equipment. This document complements the broader framework for transformer design and manufacturing, ensuring consistency in how insulation properties are evaluated globally. It provides technical clarity for manufacturers and testing laboratories involved in the certification process, facilitating the exchange of equipment across international markets by harmonizing test criteria.