Electrical, mechanical, and safety requirements are set forth for liquid-immersed distribution and power transformers, and autotransformers and regulating transformers; single and polyphase, with voltages of 601 V or higher in the highest voltage winding. This standard is the basis for the establishment of performance, limited electrical and mechanical interchangeability, and safety requirements of equipment described; and for assistance in the proper selection of such equipment. The requirements in this standard apply to all liquid-immersed distribution, power, and regulating transformers except the following: instrument transformers; step-voltage and induction voltage regulators; arc furnace transformers; rectifier transformers; specialty transformers; grounding transformers, mobile transformers; and mine transformers.

This standard is a basis for the establishment of performance, limited electrical and mechanical interchangeability, and safety requirements of equipment described. It is also a basis for assistance in the proper selection of such equipment.This standard describes electrical, mechanical, and safety requirements of liquid-immersed distribution and power transformers, and autotransformers and regulating transformers, single and polyphase, with voltages of 601 V or higher in the highest voltage winding.This standard applies to all liquid-immersed distribution, power, and regulating transformers except as indicatedbelow:1) Instrument transformers2) Step voltage and induction voltage regulators3) Arc furnace transformers4) Rectifier transformers5) Specialty transformers6) Grounding transformers7) Mobile transformers8) Mine transformersWhen this standard is used on a mandatory basis, the words shall and must indicate mandatory requirements. The words should and may refer to matters that are recommended or permissive, but not mandatory.