Methodologies for determination of the steady-state winding hottest-spot temperature in dry-type distribution and power transformers with ventilated, sealed, solid cast, and encapsulated windings built in accordance with IEEE Std C57.12.01(TM) and IEC 60726 are described in this guide. Converter transformers are not included in this guide.

This guide describes methodologies for determination of the steady-state winding hottest-spot temperature in dry-type distribution and power transformers with ventilated, sealed, solid cast, and encapsulated windings built in accordance with IEEE Std C57.12.01(TM) and IEC 60076-11. Converter transformers are not included in this guide.

Assumptions regarding the relation of winding hottest-spot temperature rise to average winding temperature rise are not representative of all dry-type transformer constructions and winding size. A uniform methodology for determination of winding hottest-spot temperature will provide consistency in testing and calculations for manufacturers' verification of the winding hottest-spot temperature to the user, and for validation and review of winding hottest-spot temperature limits.