This guide recommends a procedure to be used to perform a failure analysis.
Although the procedure may be used for an investigation into any ac transformer failure, it is primarily focused on power transformers used on electric utility systems.
IEEE Std C57.125-1991 history
2015IEEE Std C57.125-2015 Guide for Failure Investigation, Documentation, Analysis, and Reporting for Power Transformers and Shunt Reactors
1991IEEE Std C57.125-1991 Guide for failure investigation, documentation, and analysis for power transformers and shunt reactors