Superseded Standard

IEEE C37.121-2012

IEEE Guide for Switchgear - Unit Substation - Requirements

The basis for the coordination of equipment in unit substations by assisting in the selection of components is intended as the use of this guide. A variety of designs for unit substations are possible using various combinations of incoming sections, transformer sections, outgoing sections, and transition sections. It is intended that the incoming, outgoing, transformer, and transition sections included in a unit substation meet the basic requirements of applicable industry standards for those sections. This guide covers three-phase unit substations for stepdown operation in the range of 112.5 kVA or greater at primary voltages of 601 V through 38 kV.

Sponsor Committee
PE/SWG - Switchgear
Learn More About PE/SWG - Switchgear
Status
Superseded Standard
PAR Approval
2011-09-10
Superseded by
C37.121-2020
Superseding
C37.121-1989
Board Approval
2012-12-05
History
ANSI Approved:
2014-10-28
Published:
2013-02-22

Working Group Details

Society
IEEE Power and Energy Society
Learn More About IEEE Power and Energy Society
Sponsor Committee
PE/SWG - Switchgear
Learn More About PE/SWG - Switchgear
Working Group
SA/C37.121 - C37.121 - Guide for Switchgear-Unit Substation--Requirements
IEEE Program Manager
Jennifer Santulli
Contact Jennifer Santulli
Working Group Chair
Darryl Moser

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.


C37.121-2020

IEEE Guide for Switchgear--Unit Substation--Requirements

The basis for the coordination of equipment in unit substations by assisting in the selection of components is intended as the use of this guide. A variety of designs for unit substations are possible using various combinations of incoming sections, transformer sections, outgoing sections, and transition sections. It is intended that the incoming, outgoing, transformer, and transition sections included in a unit substation meet the basic requirements of applicable industry standards for those sections. This guide covers three-phase unit substations for step-down operation in the range of 112.5 kVA or greater at primary voltages of 601 V through 52 kV.

Learn More About C37.121-2020

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.


C37.121-1989

American National Standard for Switchgear - Unit Substations - Requirements

This standard covers the requirements for three-phase unit substations for step-down operation in the range of 112.5 kVA through 10 000 kVA at primary voltages of 601 volts through 38 kilovolts. The standard is intended for use as the basis for the coordination of equipment by assisting in the selection of components. A variety of designs for unit substations are possible using various combinations of incoming sections, transformer sections, outgoing sections, and transition (throat) sections. Since the transformer section determines the kVA and voltage capabilities of a unit substation, the ratings of the various types of unit substations are described in terms of transformer capability.

Learn More About C37.121-1989

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.