IEEE C57.119-2018 PDF
This recommended practice covers temperature rise test procedures for determining those thermal characteristics of power transformers needed to appraise the transformer’s load carrying capabilities at specific loading conditions other than rated load.
These recommended test procedures for performing temperature rise tests on power transformers are for the purpose of the following: a) Determining the thermal characteristics of a transformer needed to appraise the thermal performance of a transformer at loads other than nameplate rating b) Verifying that a transformer can be loaded with a specified load profile without exceeding specified temperature rise c) Assessing a transformer’s performance during transient loading, simulating a load cycle that includes loads in excess of nameplate rating
Revision Standard – Active. Recommendations are made, where possible, regarding the performance and evaluation of temperature rise tests on liquid-immersed power transformers beyond nameplate ratings in this recommended practice. The intent is to assist power transformer manufacturers, and the ultimate users, in evaluating thermal performance of the transformers under varying loads.