scope:

This guide is written primarily for power transformers, but it is also generally applicable to distribution and instrument transformers. Other standards, plus the purchaser's specifications, already determine the specific requirements for impulse tests. The purpose of this guide is not to change these standards in anyway, but to add background information that will aid in the interpretation and application of these standards. These alternates have been developed by different testing laboratories with consideration for their individual problems of transformer design, test facilities, etc. It is the objective of this guide to discuss these differences and to show how effective failure detection can be achieved with the testing techniques employed.