The National Electrical Manufacturers Association (NEMA) has published one amendment, errata, and seven reaffirmations to the ANSI C37 series for switchgear. These standards are maintained by NEMA’s Switchgear Section, and the series provides conformance test procedures for circuit breakers and switchgear used in electrical distribution systems.
ANSI C37.51a-2010 Metal-Enclosed Low-Voltage AC Power Circuit Breaker Switchgear Assemblies—Conformance Test Procedures—Amendment 1: Short-Time Withstand Current Tests amends ANSI C37.51. It was developed to coordinate selected conformance tests and procedures with ANSI/IEEE C37.20.1-2002 and to recognize that standard’s amendment, ANSI/IEEE C37.20.1a-2005. This publication provides modifications to referenced standards and information on circuit breaker compartments.
Errata were published to ANSI C37.51 to correct a typographical error in clause 5.8.2, Cycles of Operation.
In addition, the following standards were reaffirmed:
- ANSI C37.50-1989 (R1995, R2000, R2010) Low-Voltage AC Power Circuit Breakers Used in Enclosures—Test Procedures
- ANSI C37.51-2003 (R2010) Metal-Enclosed Low-Voltage AC Power Circuit Breaker Switchgear Assemblies—Conformance Test Procedures
- ANSI C37.54-2002 (R2010) Indoor Alternating Current High-Voltage Circuit Breakers Applied as Removable Elements in Metal-Enclosed Switchgear—Conformance Test Procedures
- ANSI C37.55-2002 (R2010) Medium-Voltage Metal-Clad Assemblies—Conformance Test Procedures
- ANSI C37.57-2003 (R2010) Metal-Enclosed Interrupter Switchgear Assemblies—Conformance Testing
- ANSI C37.58-2003 (R2010) Indoor AC Medium-Voltage Switches for Use in Metal-Enclosed Switchgear—Conformance Test Procedures
- ANSI C37.85-2002 (R2010) Alternating-Current High-Voltage Power Vacuum Interrupters—Safety Requirements for X-Radiation Limits
ANSI C37.51a may be downloaded at no charge, or a hardcopy purchased for $20, by visiting www.nema.org/stds/c37-51a.cfm. For ANSI C37.51, which may be downloaded at no charge or a hardcopy purchased for $61, go to www.nema.org/stds/c37-51.cfm. To learn more about the rest of the ANSI C37 series and other NEMA standards, visit www.nema.org/stds/. NEMA standards may also be purchased by contacting IHS at 800-854-7179 (within the U.S.), 303-397-7956 (international), 303-397-2740 (fax), or global.ihs.com.