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.1 Purpose This standard is intended to serve as a basis for the establishment of performance and interchangeability requirements of equipment described@ and for assistance in the proper selection of such equipment.