IEEE C57.12.01-2015

This standard describes electrical and mechanical requirements of single and polyphase ventilated, nonventilated, and sealed dry-type distribution and power transformers or autotransformers, with a voltage of 601 V or higher in the highest voltage winding. This standard applies to all dry-type transformers, including those with solid cast and/or resin-encapsulated windings except as follows: a) Instrument transformers; b) Step- and induction-voltage regulators; c) Arc-furnace transformers; d) Rectifier transformers; e) Specialty and general-purpose transformers; f) Mine transformers; g) Testing transformers; h) Welding transformers. NOTE–Where IEEE standards do not exist for the transformers mentioned above or for other special transformers, this standard may be applicable as a whole or in parts subject to agreement between the parties responsible for the application and for the design of the transformer.