Preface
This is the harmonized ANCE, CSA, and UL standard for Busways. It is the third edition of NMX-J-148-ANCE, the sixth edition of CSA C22.2 No. 27, and the thirteenth edition of UL 857. This edition of CSA C22.2 No. 27 supersedes the previous edition published in 2000. This harmonized standard has been jointly revised on December 9, 2011. For this purpose, CSA and UL are issuing revision pages dated December 9, 2011, and ANCE is issuing a new edition dated December 9, 2011.
This harmonized standard was prepared by the Association of Standardization and Certification (ANCE), the Canadian Standards Association (CSA), and Underwriters Laboratories Inc., (UL). The efforts and support of the CANENA Busway Technical Harmonization Committee are gratefully acknowledged.
This Standard is considered suitable for use for conformity assessment within the stated scope of the Standard.
The present Mexican Standard was developed by the CT CDI from the Comite de Normalizacion de la Asociacion de Normalizacion y Certificacion, A.C., CONANCE, with the collaboration of the busway manufacturers and users.
This standard was reviewed by the CSA Subcommittee on Busways, under the jurisdiction of the CSA Technical Committee on Industrial Products and the CSA Strategic Steering Committee on Requirements for Electrical Safety, and has been formally approved by the CSA Technical Committee.
This standard has been approved by the American National Standards Institute (ANSI) as an American National Standard.
Where reference is made to a specific number of samples to be tested, the specified number is to be considered a minimum quantity.
Note: Although the intended primary application of this standard is stated in its scope, it is important to note that it remains the responsibility of the users of the standard to judge its suitability for their particular purpose.
Scope
1.1.1
This Standard applies to service-entrance, feeder, and branch-circuit busways and associated fittings rated at 600 V or less, 6 000 A or less, and intended for use in accordance with the Canadian Electrical Code, Part I (CE Code, Part I), the National Electrical Code (NEC), NFPA 70, and the Mexican Standard for Electrical Installations (Utility), NOM-001-SEDE, (see Annex B, Reference Item No. 1).
These requirements do not apply to metal enclosed bus intended for connecting switchgear assemblies for use in prefabricated electric distribution systems.
1.1.2
For the purpose of these requirements, a busway is considered to be a grounded metal enclosure containing factory mounted conductors that are usually copper or aluminum bars, rods, or tubes.
1.1.3
Values stated without parentheses are the requirement. Values in parentheses are explanatory or approximate information.
1.1.4
Unless otherwise indicated, all voltage and current values mentioned in this Standard are root-mean-square (rms).