Superseded Standard

IEEE 421-1972

IEEE Standard Criteria and Definitions for Excitation Systems for Synchronous Machines

This document presents criteria, essential elements, and new and revised definitions for excitation systems as applied to electric utility synchronous machines with particular emphasis given to the application of solid-state devices and to terminology common to feedback control systems.

Status
Superseded Standard
Superseded by
421.1-1986
Board Approval
1971-12-02
History
Published:
1972-12-08

Working Group Details

Other Activities From This Working Group

Current projects that have been authorized by the IEEE SA Standards Board to develop a standard.


No Active Projects

Standards approved by the IEEE SA Standards Board that are within the 10-year lifecycle.


No Active Standards

These standards have been replaced with a revised version of the standard, or by a compilation of the original active standard and all its existing amendments, corrigenda, and errata.


No Superseded Standards

These standards have been removed from active status through a ballot where the standard is made inactive as a consensus decision of a balloting group.


No Inactive-Withdrawn Standards

These standards are removed from active status through an administrative process for standards that have not undergone a revision process within 10 years.


No Inactive-Reserved Standards
Subscribe to our Newsletter

Sign up for our monthly newsletter to learn about new developments, including resources, insights and more.