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  • UL 857:13ED 2009-03

    Current The latest, up-to-date edition.

    Busways

    Available format(s):  Hardcopy

    Language(s):  English

    Published date:  25-03-2009

    Publisher:  Underwriters Laboratories

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    Table of Contents - (Show below) - (Hide below)

    FOREWORD
    INTRODUCTION
    1. Scope
    2. General
    CONSTRUCTION
    ALL PRODUCTS
    3. General
    4. Enclosure
    5. Grounding
    6. Busway Supports
    7. Transverse Barriers
    8. Bus Bar Supports
    9. Current-Carrying Parts
    10. Bus Bar Coverings
    11. Wiring Terminals
    12. Spacings
    13. Wiring Space
    VENTILATED BUSWAY
    14. Enclosure
    15. Bus Bar Coverings
    16. Spacings
    UNVENTILATED BUSWAY
    17. Enclosure
    TROLLEY BUSWAY
    18. General
    19. Enclosure
    PLUG-IN BUSWAY AND FITTINGS
    20. General
    21. Enclosure
    OUTDOOR BUSWAY AND FITTINGS
    22. General
    23. Enclosure
    FITTINGS
    24. General
    25. Fittings Suitable for Use as Service Equipment
    26. Enclosure
    27. Live Parts
    28. Spacings
    SHORT-RUN BUSWAY
    29. General
    30. Enclosure
    31. Busway Supports
    32. Bus Bar Supports
    33. Current Carrying Parts
    34. Spacings
    35. Ratings
    36. Markings
    PERFORMANCE
    37. Heating Test
    38. Endurance Test of Trolley Busway
    39. Electrical Conductivity Test
    40. Enclosure Joint Short-Time Fault Current Test
    41. Overload and Endurance Tests
    42. Resistance to Aging Test
    43. Dielectric Voltage-Withstand Tests
    44. Resistance to Impact Test
    45. Resistance to Bending Test
    46. Resistance to Crushing Test
    47. Bus-Bar Pullout Test
    48. Strain Relief Test
    49. Metallic Coating Thickness Test
    50. Insulation Resistance And Dielectric Voltage-Withstand
         after Exposure to Rain Tests
    51. Short Circuit Test
    52. Short Circuit Test at Reduced Voltage
    53. Strength of Insulating Base and Support Test
    RATINGS
    54. General
    MARKINGS
    55. General
    56. Permanence of Marking
    INSTALLATION INSTRUCTIONS
    57. Field Testing of Ground Fault Protection of Equipment
    APPENDIX A
    Standards for Components

    Abstract - (Show below) - (Hide below)

    This revision of ANSI/UL 857 dated April 9, 2021 is being issued to update the title page to reflect the most recent designation as a Reaffirmed American National Standard (ANS).

    Scope - (Show below) - (Hide below)

    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).

    General Product Information - (Show below) - (Hide below)

    Development Note Supersedes NEMA BU 2. (08/2001) Also numbered as CSA C22.2.27 & ANCE NMX-J-148. (03/2009)
    Document Type Standard
    Publisher Underwriters Laboratories
    Status Current
    Supersedes

    Standards Referenced By This Book - (Show below) - (Hide below)

    IEEE C37.23-2003 IEEE Standard for Metal-Enclosed Bus
    NFPA 70B:2023 Standard for Electrical Equipment Maintenance
    NEMA BU 1.2:2002(R2013) Application Information for Busway Rated 600 V or Less
    IEEE 141 : 1993 IEEE Recommended Practice for Electric Power Distribution for Industrial Plants
    NEMA BU 2 : 1996 MAJOR REQUIREMENTS RELATED TO THE APPLICATION AND TESTING OF LOW VOLTAGE BUSWAY
    UL 183:4ED 2009-09 Manufactured Wiring Systems
    NFPA 70 : 2017 NATIONAL ELECTRICAL CODE
    IEEE 241 : 1990 ELECTRIC POWER SYSTEMS IN COMMERCIAL BUILDINGS
    IEEE 3001.5-2013 IEEE Recommended Practice for the Application of Power Distribution Apparatus in Industrial and Commercial Power Systems
    IEEE 242-2001 IEEE Recommended Practice for Protection and Coordination of Industrial and Commercial Power Systems (IEEE Buff Book)

    Standards Referencing This Book - (Show below) - (Hide below)

    UL 50:13ED 2015-10 Enclosures for Electrical Equipment, Non-Environmental Considerations
    UL 977:5ED 2012-04 Fused Power-Circuit Devices
    UL 248-8:3ED 2011-05 Low-Voltage Fuses - Part 8: Class J Fuses
    UL 869A:4ED 2006-11 Standard for Reference Standard for Service Equipment
    UL 83:16ED 2017-07 Standard for Thermoplastic-Insulated Wires and Cables
    UL 248-12:3ED 2011-05 Low-Voltage Fuses - Part 12: Class R Fuses
    UL 248-4:2ED 2000-08 Low-Voltage Fuses - Part 4: Class CC Fuses
    UL 248-10:3ED 2011-05 Low-Voltage Fuses - Part 10: Class L Fuses
    UL 746A:6ED 2012-09 Polymeric Materials - Short Term Property Evaluations
    UL 248-1 : 3 LOW-VOLTAGE FUSES - PART 1: GENERAL REQUIREMENTS
    UL 1332:5ED 2016-02 Standard for Organic Coatings for Steel Enclosures for Outdoor Use Electrical Equipment
    UL 4248-15:1ED 2007-02 Fuseholders - Part 15: Class T
    UL 4248-4:1ED 2007-02 Fuseholders - Part 4: Class CC
    UL 414:9ED 2016-01 Meter Sockets
    UL 248-5:2ED 2000-08 Standard for Low-Voltage Fuses - Part 5: Class G Fuses
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