IEEE C37.234-2021

Concepts of power bus protection are discussed in this guide. Consideration is given to availability and location of breakers, current sensing devices, and disconnect switches, as well as bus-switching scenarios, and their impact on the selection and application of bus protection. A number of bus protection schemes are presented; their adequacy, complexity, strengths, and limitations with respect to a variety of bus arrangements are discussed; specific application guidelines are provided. Breaker failure (BF) protection is discussed as pertaining to bus protection. Means of securing bus protection schemes against corrupted relay input signals are also included.

The purpose of the guide is to assist utility engineers and industrial and commercial plant engineers in selecting and engineering proper bus protection.

Revision Standard - Active. Principles of power bus protection are discussed. The availability and location of breakers, current sensing devices, and disconnect switches are addressed, as well as bus configurations and switching schemes and their impact on the selection and application of bus protection. Bus protection schemes are presented, and their characteristics, strengths, and limitations are examined. Bus protection applications are presented.