IEEE C57.12.90:1993

Revision Standard - Superseded.
Replaced by IEEE Std C57.12.90-1999 (SH/SS94778) Abstract: Methods for performing tests specified in IEEE Std C57.12.00-1993, IEEE Standard General Requirements for Liquid-Immersed Distribution, Power, and Regulating Transformers, and other standards applicable to liquid-immersed distribution, power, and regulating transformers are described. Instrument transformers, step-voltage and induction voltage regulators, arc furnace transformers, rectifier transformers, specialty transformers, grounding transformers, and mine transformers are excluded. This standard covers resistance measurement, polarity and phase-relation tests, ratio tests, no-load-loss and excitation current measurements, impedance and loadloss measurements, dielectric tests, temperature tests, short-circuit tests, and audible-sound-level measurements.

This standard describes methods for performing tests specified in IEEE Std C57.12.00-1993 and other standards applicable to liquid-immersed distribution, power, and regulating transformers. It is intended for use as a basis for performance, safety, and the proper testing of such transformers. This standard applies to all liquid-immersed transformers except instrument transformers, step-voltage and induction voltage regulators, arc furnace transformers, rectifier transformers, specialty transformers, grounding transformers, and mine transformers. When this standard is used on a mandatory basis, the words shall and must indicate mandatory requirements; and the words should or may refer to matters that are recommended or permitted, but not mandatory.
The purpose of this standard is to provide test procedure information. Transformer requirements and specific test criteria are not a part of this standard but are contained in appropriate standards, such as IEEE Std C57.12.00-1993, ANSI Std C57.12.10-1987, ANSI Std C57.12.20-1988, ANSI Std C57.12.40-1990, or in user specifications.