UL 5085-1
Low Voltage Transformers - Part 1: General Requirements

DETAILS
Edition Number:1SCC Approved:--
Edition Date:2006-04-17DOD Approved: --
Price Code:CANSI Approved: 2013-12-06
Type:ulcsa

  • SCOPE

    1 Scope

    1.1 These requirements cover the following types of transformers:

    a)    Air-cooled transformers and reactors for general use;

    b)    General purpose autotransformers;

    c)    Ferroresonant transformers;

    d)    Class 2 and Class 3 transformers (which are evaluated in accordance with Part 3);

    e)    Cord-connected transformers (which are evaluated in accordance with Part 2);

    f)    Transformers incorporating overcurrent or over-temperature protective devices, transient voltage surge protectors, or capacitors; and

    g)    Permanently-connected transformers.

    1.2 These transformers are intended to be used in accordance with the National Electrical Code, ANSI/NFPA 70, or CSA C22.1, the Canadian Electrical Code, Part I. The Canadian Electrical Code defines low voltage as any voltage from 31 to 750 V inclusive and high voltage as any voltage above 750 V. The National Electrical Code, ANSI/NFPA 70, defines low voltage as any voltage up to 600 V, nominal. Therefore, low voltage transformers intended for use in Canada may be rated above 600 V up to 750 V. Low voltage transformers intended for use in the United States are rated up to 600 V. Where information in clauses and tables in this standard reference voltage ranges, the limit of 600 V applies in the United States, while the limit of 750 V applies in Canada.

    1.3 The standard does not cover the following transformers:

    a)    Direct plug-in types;

    b)    Neon;

    c)    Liquid-immersed;

    d)    Variable voltage (Variac);

    e)     Low voltage landscape;

    f)    Swimming pool and spa:

    g)    Ignition;

    h)    High intensity lighting;

    i)    Toy;

    j)    Fluorescent lamp types;

    k)    Transformers for welders;

    l)    Distribution;

    m)    Transformers intended for use in the United States with a nominal primary rating of more than 600 V;

    n)    Transformers incorporating rectifying or waveshaping circuitry;

    o)    Transformers for use with radio- and television-type appliances;

    p)    Transformers intended for use in the United States having overvoltage taps rated over 660 V;

    q)    Autotransformers used in industrial control equipment, which are evaluated in accordance with the requirements of the Standard for Industrial Control Equipment, UL 508, or CSA C22.2 No. 14,  Industrial Control Equipment; and

    r)    Other special types of transformers covered in requirements for other electrical devices or appliances.

    1.4 Part 1, as well as Part 2 and Part 3, establish the characteristics, construction, operating conditions, markings, and test conditions for each type of transformer.

    1.5 The requirements in this standard may be modified by requirements in an end product standard if a transformer is intended for use only as a component in other equipment.

  • TABLE OF CONTENTS
    Expand All

    • Cover
    • Transmittal
    • UL Harmonized Standard Title Page
    • Table of Contents
      • PART 1: GENERAL REQUIREMENTS
        • 1 Scope
        • 2 Definitions
        • 3 General
          • 3.1 Components
          • 3.2 Reference Publications
          • 3.3 Units of Measurement
        • 4 Construction
        • 5 Mechanical Assembly
        • 6 Enclosures
          • 6.1 General
          • 6.2 Nonmetallic enclosures
          • 6.3 Enclosures – specific environmental conditions
          • 6.4 Mounting
          • 6.5 Openings
          • 6.6 Barriers for openings
          • 6.7 Covers
        • 7 Corrosion Resistance
        • 8 Connections
          • 8.1 General
          • 8.2 Wiring terminals
          • 8.3 Wire-binding screws and studs
          • 8.4 Pressure terminal connectors
          • 8.5 Leads
        • 9 Internal Wiring
        • 10 Grounding
        • 11 Spacings and Insulation
          • 11.1 General
          • 11.2 Insulating material for mounting of low voltage live parts
          • 11.3 Coil insulation
          • 11.4 Insulation used in lieu of spacings
          • 11.5 Double insulation
        • 12 Switches, Protective Devices, and Wiring Devices
          • 12.1 General
          • 12.2 Switches
          • 12.3 Protective devices
        • 13 Current-Carrying Parts
        • 14 Cord-Connected Transformers
        • 15 Strain Relief
        • 16 Bushings for Low Voltage Wiring
        • 17 Markings
          • 17.1 General
          • 17.2 Miscellaneous
        • 18 Tests
        • 19 Insulating Barriers Test
        • 20 Pullout, Bending, and Twisting Tests
        • 21 Bonding Conductor Test
        • 22 Moisture Absorption Test
        • 23 Hot, Flaming Oil Test
        • 24 Enclosure Tests
          • 24.1 General
          • 24.2 Compression test
          • 24.3 Outlet box cover support and impact tests
          • 24.4 Polymeric enclosure impact test
        • 25 Induced Potential
        • 26 Temperature (Heating) Test
    • Annex A (Informative)
    • Annex B (Informative)
    • Annex C (Informative)