CSA C22.2 No. 244:19

National Standard of Canada

Switchboards

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  CSA C22.2 No. 244:19

  July 2019

  
  

  Title: Switchboards

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National Standard of Canada

CSA C22.2 No. 244:19

Switchboards

®A trademark of the Canadian Standards Association, operating as “CSA Group”

ICS 29.130.01

JULY 19, 2019 tr1

Standard for Safety for Switchboards Dated July 19, 2019

Summary of Topics

This new edition covers switchboards nominally rated at 1 000 V or less and intended for use in accordance with CSA C22.1, Canadian Electrical Code, Part I (CE Code, Part I), the National Electrical Code (NEC), ANSI/NFPA 70, and the Mexican Standard for Electrical Installations (Utility), NOM-001-SEDE.

tr2 JULY 19, 2019

No Text on This Page

Association of Standardization and Certification NMX-J-118/2-ANCE-2019

Fourth Edition

CSA Group

CSA C22.2 No. 244:19

Second Edition

Underwriters Laboratories Inc. UL 891

Twelfth Edition

Switchboards

July 19, 2019

ANSI/UL 891-2019

Commitment for Amendments

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JULY 19, 2019

NMX-J-118/2-ANCE-2019 ♦ CSA C22.2 No. 244:19 ♦ UL

891 3

CONTENTS

Preface 5

1. General 7

   1. Scope and object 7

2. General 7

   1. Undated references 7

   2. Multiple countries codes 7

   3. Products for Canada 7

   4. Components 7

3. Definitions 8

4. Units of measurement 12

5. Electrical characteristics of assemblies 12

   1. General 12

   2. Rated voltages 12

   3. Continuous current rating 12

   4. Short-circuit current rating 13

   5. Rated peak withstand current (Ipk) (of a circuit of an assembly) 13

   6. Rated conditional short-circuit current (Icc) (of a circuit of an assembly) 13

   7. Rated fused short-circuit current (Icf) (of a circuit of an assembly) 13

   8. Rated diversity factor 13

   9. Rated frequency 13

6. Information to be given regarding the assembly 13

   1. Nameplates 13

   2. Markings 14

   3. Instructions for installation, operation and maintenance 26

7. Service conditions 27

   1. Normal service conditions 27

   2. Special service conditions 28

   3. Conditions during transport, storage, and erection 28

8. Design and construction 28

   1. Mechanical design 28

   2. Enclosure and degree of protection 42

   3. Temperature rise 45

   4. Protection against electric shock 45

   5. Short-circuit protection and short-circuit withstand strength 52

   6. Switching devices and components installed in assemblies 53

   7. Internal separation of assemblies by barriers or partitions 64

   8. Electrical connections inside an assembly: bars and insulated conductors. 66

   9. Requirements for electronic equipment supply circuits 81

   10. Electromagnetic compatibility 81

9. Test specifications 81

   1. Classification of tests 81

   2. Type tests. 82

   3. Routine tests 97

10. Tables 98

11. Figures 121

Annex A (Informative) Standards for Components

Annex B (Normative) Standards Referenced in the Trinational Switchboard Standard

NMX-J-118/2-ANCE-2019 ♦ CSA C22.2 No. 244:19 ♦ UL

4 891 JULY 19, 2019

Annex C (Informative) Markings Required to be Translated and Suggested French Translations

Annex D (Informative) Example of Series Short-Circuit Current Rating Marking

Annex E (Informative) Example of Terminal Torque Marking

Annex F (normative) Short-Circuit Test at Reduced Voltage

F1 Voltage 146

F2 Current 146

Annex G (normative) Maximum 100 000 Ampere Short-Circuit Current Rating Without Short-Circuit Test

G1 Scope 152

G2 Glossary 152

G3 Construction 152

G3.1 General 152

G3.2 Spacings 166

G3.3 Supports 167

G4 Performance 167

G4.1 General 167

G4.2 Tensile 167

G4.3 Cantilever 169

G5 Marking 169

Supplement SA Use of Components Not UL Listed or Recognized (For U.S. Only)

SA1 Scope 171

SA2 Conditions of Use 171

SA3 Overcurrent Protections 174

SA4 Circuit Breaker and Ground Fault Circuit Interrupter 174

SA5 Tests and Records By the Manufacturer 175

JULY 19, 2019

NMX-J-118/2-ANCE-2019 ♦ CSA C22.2 No. 244:19 ♦ UL

891 5

Preface

This is the harmonized ANCE, CSA Group, and UL standard for Switchboards. It is the Fourth edition of NMX-J-118/2-ANCE, the Second edition of CSA C22.2 No. 244, and the Twelfth edition of UL 891. This edition of NMX-J-118/2-ANCE supersedes the previous edition published on October 31, 2012. This edition of CSA C22.2 No. 244 supersedes the previous edition published on July 26, 2005. This edition of UL 891 supersedes the previous edition published on July 26, 2005.

This harmonized standard was prepared by the Association of Standardization and Certification, (ANCE), CSA Group and Underwriters Laboratories Inc. (UL). The efforts and support of the Technical Harmonization Subcommittee, 17D – Panelboard and Switchboard on the Harmonization of Electrotechnical Standards of the Nations of the Americas (CANENA), 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 Control y Distribucion Industrial from the Comite de Normalizacion de la Asociacion de Normalizacion y Certificacion, A. C., CONANCE, with the collaboration of the switchboard manufacturers and users.

This standard was reviewed by the CSA Integrated Committee on Switchgear Products, 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 Com m ittee.This standard has been developed in com pliance with Standards Council of Canada requirements for National Standards of Canada. It has been published as a National Standard of Canada by CSA Group.

Application of 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.

Level of harmonization

This standard is published as an equivalent standard for ANCE, CSA Group and UL.

An equivalent standard is a standard that is substantially the same in technical content, except as follows: Technical national differences are allowed for codes and governmental regulations as well as those recognized as being in accordance with NAFTA Article 905, for example, because of fundamental climatic, geographical, technological, or infrastructural factors, scientific justification, or the level of protection that the country considers appropriate. Presentation is word for word except for editorial changes.

Interpretations

The interpretation by the standards development organization of an identical or equivalent standard is based on the literal text to determine compliance with the standard in accordance with the procedural rules of the standards development organization. If more than one interpretation of the literal text has been identified, a revision is to be proposed as soon as possible to each of the standards development organizations to more accurately reflect the intent.

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6 891 JULY 19, 2019

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JULY 19, 2019

NMX-J-118/2-ANCE-2019 ♦ CSA C22.2 No. 244:19 ♦ UL

891 7

Switchboards

1. General

   
   

   1. Scope and object

      
      

      1. This Standard applies to switchboards nominally rated at 1 000 V or less and intended for use in accordance with the Canadian Electrical Code, Part I (CE Code, Part I), the National Electrical Code (NEC), ANSI/NFPA 70, and the Mexican Standard for Electrical Installations (Utility), NOM-001-SEDE.

         
         

      2. In this standard the term switchboard is intended to refer to a dead-front switchboard.

         
         

      3. These requirements do not cover the following switchboard types: preset and dimmer control (theater), live front, railway control or electrification; or constructions intended only for receiving motor control center units.

         
         

      4. These requirements cover switchboards for use on circuits having available short-circuit currents of not more than 200 000 A.

         
         

      5. These requirements do not cover switchboards with short-time current ratings.

         
         

2. General

   
   

   1. Undated references

      
      

      1. For undated references to standards, such reference shall be considered to refer to the latest edition and all revisions to that edition up to the time when this standard was approved. For dated references to standards, such reference shall be considered to refer to the dated edition and all revisions published to that edition up to the time the standard was approved. See Annex B.

         
         

   2. Multiple countries codes

      
      

      1. When compliance with multiple countries' codes or Standards is required, but the product is not intended for use in all three countries, the product need only comply with the codes or Standards for the country or countries in which it is intended to be used.

2.3 Products for Canada

2.3.1 For products intended for use in Canada general requirements are given in Reference Item No. 15 of Annex B.

2.4 Components

2.4.1 A component of a product covered by this standard shall comply with the requirements for that component. See Annex A for a list of Standards covering components generally used in the products covered by this Standard. A component shall comply with the Underwriters Laboratories Inc. Standards, the ANCE Standards, and the Canadian Standards Association Standards for the component. When a product is not intended for use in all three countries, a component need only comply with the component Standards for the country or countries in which it is intended to be used.

2.4.1.1 A component need not comply if it is: