IEEE C57.119-2001

Write Recommended Practice for performing Temperature Rise Tests on Power Transformers for the purpose of: A. Determining the Thermal Characteristics of a transformer required to calculate the Thermal Performance of a Transformer loaded at Loads other than name plate rating. B. Verify that a Transformer can be loaded with a specified load profile without exceeding specified Temperature Rises. C. Asses a Transformer performance during loading simulating A LOAD CYCLE including loads in excess of nameplate rating. Present Standard Temperature Rise Tests, to verify the rating, do not provide adequate data to evaluate transformer temperature rises at load cycles beyond Nameplate Ratings. This recommended practice document provides the additional data required for assessing transformer temperature under time-varying loads. New IEEE Standard - Superseded. Reaffirmed 2008. Recommendations are made, where possible, regarding the performance and evaluation of temperature rise tests on oil-immersed power transformers beyond nameplate ratings. The intent is to assist power transformer manufacturers, and the ultimate users, in evaluating thermal performance of the transformers under varying loads.