IEEE C57.12.51:2019

Revision Standard - Active.
Characteristics of ventilated dry-type transformers relating to performance, limited electrical and mechanical interchangeability, as well as recommended practice for installation of equipment are set forth in this guide. Specific rating combinations are described up to 7500 kVA high-voltage class from 1.2 kV to 36 kV inclusive, and low voltage class up to 5 kV. This guide also describes certain electrical and mechanical requirements and takes into consideration certain desirable features of 60 Hz, two-winding, three-phase, ventilated dry-type transformers. Clause 9 through Clause 11 describe other requirements or alternatives that may be specified for some applications.

This guide sets forth characteristics of ventilated dry-type transformers relating to performance, limited electrical and mechanical interchangeability, as well as recommended practice for installation of the equipment described, and to assist in the proper selection of such equipment. Specific rating combinations are described up to a base of 7500 kVA inclusive, high-voltage class from 1.2 kV to 36 kV inclusive, and low-voltage class up to 5 kV. This guide does not apply to other types of transformers such as specialty, sealed dry-type, pad-mounted drytype, instrument, step and induction voltage regulators, arc-furnace, mining, testing, welding, and rectifier transformers.