UL 1971
Standard for Signaling Devices for the Hearing Impaired

DETAILS
Edition Number:3SCC Approved:--
Edition Date:2002-11-29DOD Approved: --
Price Code:AANSI Approved: 2018-08-29
Type:ulstd

  • SCOPE

    1 Scope

    1.1 These requirements cover emergency-signaling devices for the hearing impaired. The devices and/or systems covered by this standard are suitable for use in a controlled environment, or in an uncontrolled environment as indicated in the product marking. These devices are to be used in accordance with the requirements of the National Fire Alarm Code, NFPA 72.

    1.2 A signaling device as covered by these requirements consists of a unit assembly of electrical parts having provision for the connection of power supply circuits routed through the equipment by a prescribed scheme of circuiting. Also included are circuits that extend to separate devices by which additional units are actuated for signals. An installation wiring diagram attached to the product, or referenced in the product marking, indicates the devices and circuits that are acceptable for connection to the signaling device.

    1.3 These requirements are to evaluate visible signaling appliances for public mode operation. These appliances are designed to alert occupants or inhabitants within the protected area. These requirements do not cover lights intended for private mode fire alarm signaling, lights intended for non-fire-alarm signaling applications, manual boxes, automatic fire detectors, or other initiating devices; nor do they cover bells, registers, or other indicating devices not provided as part of the product.

    1.4 Deleted

  • TABLE OF CONTENTS
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    • Cover
    • Transmittal
    • Table of Contents
    • UL Foreword
      • Body
        • INTRODUCTION
          • 1 Scope
          • 2 General
            • 2.1 Components
            • 2.2 Units of measurement
            • 2.3 Undated references
          • 3 Glossary
          • 4 Instructions and Drawings
        • CONSTRUCTION
          • 5 Enclosures
            • 5.1 General
            • 5.2 Cast metal
            • 5.3 Sheet metal
            • 5.4 Plastic
            • 5.5 Wood
          • 6 Covers
            • 6.1 General
            • 6.2 Transparent covers
          • 7 Ventilating Openings
          • 8 Corrosion Protection
          • 9 Insulating Materials
          • 10 Mounting of Parts
          • 11 Operating Mechanisms
          • 12 Field-Wiring Connections – Permanently-Connected Products
            • 12.1 General
            • 12.2 Field-wiring terminal connections
            • 12.3 Field-wiring terminals and leads
            • 12.4 Identified terminal and leads
          • 13 Field-Wiring Connections – Cord-Connected Products
            • 13.1 General
            • 13.2 Cords and plugs
            • 13.3 Strain relief
            • 13.4 Bushings
          • 14 Polarization
          • 15 Current-Carrying Parts
          • 16 Internal Wiring
            • 16.1 General
            • 16.2 Splices and connections
          • 17 Interconnecting Cords and Cables
          • 18 External Circuit Connections
            • 18.1 Separation of circuits
            • 18.2 Terminal and connectors
          • 19 Printed-Circuit Boards
          • 20 Motor Overcurrent Protection
          • 21 Grounding for Products Connected to the Branch Circuit
          • 22 Class 2 Power Units
          • 23 Spacings
          • 24 Servicing Protection
            • 24.1 General
            • 24.2 Electric shock
        • PERFORMANCE
          • 25 General
          • 26 Normal Operation and Electrical Supervision Tests
          • 27 Signal Strength and Format Test
            • 27.1 General
            • 27.2 Light output measurements
            • 27.3 Optional black box test procedure
            • 27.4 Quadrant vector alignment
          • 28 Synchronization of Light Output Test
          • 29 Electrical Measurements
          • 30 Variable Voltage Operation Test
          • 31 Component Temperature Test
          • 32 Environmental Tests
          • 33 Overload Test
            • 33.1 Signaling devices
            • 33.2 Signaling systems
          • 34 Endurance Test
            • 34.1 Signaling devices
            • 34.2 Signaling systems
          • 35 Transient Tests
            • 35.1 General
            • 35.2 Supply line transients
            • 35.3 Internally induced transients
            • 35.4 Signal circuit transients
          • 36 Vibration Test
          • 37 Electric Shock Current Test
          • 38 Leakage Current Test
          • 39 Dielectric Voltage-Withstand Test
          • 40 Component Failure Test
          • 41 Abnormal Operation and Burnout Test
          • 42 Drop Test
          • 43 Impact Test
          • 44 Crush Test
          • 45 Strain Relief Test
          • 46 Indoor Corrosion Test
          • 47 Special Terminal Assemblies Tests
        • INSTALLATION AND OPERATING INSTRUCTIONS
          • 48 General
        • MARKINGS
          • 49 General
          • 50 Permanence of Marking
    • APPENDIX A