UL 1008A
Transfer Switch Equipment, Over 1000 Volts

DETAILS
Edition Number:2SCC Approved:--
Edition Date:2017-09-05DOD Approved: --
Price Code:BANSI Approved: 2017-09-05
Type:ulcsa

  • SCOPE

    1 Scope

    1.1 These requirements cover automatic, non-automatic, and manual transfer switches, operating at voltages of greater than 1000 Vac, and intended for use in non-hazardous locations in accordance with Annex b, Item 1, the National Electrical Code, ANSI/NFPA 70, or the Canadian Electrical Code, CSA C22.1, Part 1, to provide for power as follows:

    a)    Automatic transfer switches for use in emergency systems in:

    1)    Emergency systems in accordance with the Standard for Emergency Electrical Power Supply for Buildings, CSA C282-15;

    2)    Health care facilities in accordance with Rule 24-304 of the Canadian Electrical Code (CEC) Part I;

    3)    Articles 517, Health Care Facilities, and 700, Emergency Systems, of the National Electrical Code, ANSI/NFPA 70 (refer to Annex b, Item 1); and

    4)    The Health Care Facilities Code, ANSI/NFPA 99, (refer to Annex b, Item 12).



    Note: Transfer switches for optional standby systems are not recognized in Canada.

    b)    Transfer switches for use in optional standby systems in accordance with Article 702 of the National Electrical Code, ANSI/NFPA 70 (refer to Annex b, Item 1). Note: Automatic transfer switches for optional standby systems are not recognized in Canada.

    c)    In legally required standby systems in accordance with Article 701 of the National Electrical Code, ANSI/NFPA 70(refer to Annex b, Item 1). Note: Legally-required standby systems are not recognized in Canada.

    d)    Automatic transfer switches for use in accordance with the Standard for the Installation of Stationary Pumps for Fire Protection, ANSI/NFPA 20 or the Standard for Fire Pump Controllers, CSA C22.2 No. 263, (refer to Annex b, Item 2).

    1.2 These requirements cover transfer switches rated greater than 1000 V to 46 kV.

    1.3 These requirements cover transfer switches together with their associated control devices including, but not limited to, voltage sensing relays, frequency sensing relays, and time delay relays.

    1.4 An automatic transfer switch as covered by these requirements is a device that automatically transfers a common load from a normal supply to an alternate supply in the event of failure of the normal supply, and automatically returns the load to the normal supply when the normal supply is restored. An automatic transfer switch can be provided with a logic control circuit that inhibits automatic operation of the device from either a normal to an alternate supply, or from an alternate to a normal supply when the switch reverts to automatic operation upon loss of power to the load.

    1.5 A non-automatic transfer switch as covered by these requirements is a device, operated manually by a physical action, or electrically by a remote control, for transferring a common load between a normal and alternate supply.

    1.6 These requirements only cover completely enclosed transfer switches.

  • TABLE OF CONTENTS
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    • Cover
    • Transmittal
    • UL Harmonized Standard Title Page
    • Table of Contents
      • Body
        • INTRODUCTION
          • 1 Scope
          • 2 General Requirements
          • 3 Units of Measurement
          • 4 Reference Publications
          • 5 Definitions
        • CONSTRUCTION
          • 6 General
          • 7 Enclosure
          • 8 Insulating Material
          • 9 Mounting of Parts
          • 10 Guarding and Accessibility of Live Parts
          • 11 Current-Carrying Parts
          • 12 Field Wiring Terminals for Control Circuits
          • 13 Internal Wiring
            • 13.1 General
            • 13.2 Barriers defining wireways
            • 13.3 Wiring in circuits below 1000 V
            • 13.4 Wiring in circuits operating at 1000 V and higher
          • 14 Isolation
            • 14.1 Isolating means
            • 14.2 Isolation of circuits
          • 15 Grounding and Bonding
            • 15.1 Terms
            • 15.2 Grounding of exposed metal parts
            • 15.3 Ground bus
            • 15.4 Provision for ground termination
            • 15.5 Grounding of drawout elements
            • 15.6 Grounding of instrument and control circuits
            • 15.7 Grounding and bonding of neutral circuits for service entrance transfer switches
          • 16 Operating Mechanism
            • 16.1 General
            • 16.2 Transfer switch operator interlocks
            • 16.3 Location and protection of transfer control circuits
            • 16.4 Transfer switches for emergency use
          • 17 Overcurrent and Ground-Fault Protection
            • 17.1 Overcurrent protection
            • 17.2 Ground-fault protection
          • 18 Receptacles
          • 19 Spacings
            • 19.1 General
            • 19.2 Spacings on printed-wiring boards operating at 1500 V or less
          • 20 Wiring Space
          • 21 Interlocking
          • 22 Transfer Switches for Service Equipment Use – Requirements for All Countries
          • 23 Service Equipment for Use in the United States
            • 23.1 Service disconnecting means
            • 23.2 Grounding and bonding of neutral circuits
          • 24 Service Equipment for Use in Canada
            • 24.1 Service disconnecting means
            • 24.2 Grounding and bonding of neutral circuits
          • 25 Transfer Switches Comprised of Circuit Breakers in Switchgear
          • 26 Transfer Switches Comprised of Contactors
          • 27 Transfer Switches Comprised of Load Interrupter Switches in Metal Enclosed Switchgear
        • PERFORMANCE
          • 28 General
          • 29 Transfer Switches Comprised of Circuit Breakers in Switchgear
          • 30 Transfer Switches Comprised of Contactors
          • 31 Transfer Switches Comprised of Load Interrupting Switches in Metal Enclosed Switchgear
          • 32 Other Transfer Switches
          • 33 Operations Tests
            • 33.1 Normal operational tests
            • 33.2 Closed transition switch normal operation test
          • 34 Overvoltage Test
          • 35 Undervoltage Test
          • 36 Range of Operating Voltages
          • 37 Overload Test
          • 38 Electrical Endurance Test
          • 39 Temperature Test
          • 40 Mechanical Endurance Tests
          • 41 Dielectric Voltage-Withstand Test
            • 41.5 Test Across Isolating Distance
          • 42 Partial Discharge Testing Procedures
            • 42.2 Test procedure
          • 43 Dielectric Voltage-Withstand Test (Repeated)
          • 44 Withstand Test
          • 45 Closing Test
          • 46 Short-Time Current Rating Test
          • 47 Momentary Withstand Current Test
            • 47.1 General
            • 47.2 Momentary tests on primary bus and connections
            • 47.3 Momentary tests on ground bus
          • 48 Dielectric Voltage-Withstand Test (Reduced Level)
          • 49 Switching Capacity Test – Isolating Means
          • 50 Isolating Means Interlock Integrity Test
          • 51 Transfer Switch Operator Interlock Integrity Test
          • 52 Impulse Voltage Withstand Tests
            • 52.7 Test across isolating distance
          • 53 Enclosure Ground Integrity Test
        • RATINGS
          • 54 Ratings
        • MANUFACTURING AND PRODUCTION TESTS
          • 55 Power-Frequency Voltage Withstand Test
            • 55.1 General
            • 55.2 Tests at the "Common value" test voltage specified in Table , Column 2
            • 55.3 Tests at the "Across the isolating distance" voltage specified in Table , Column 3
        • MARKINGS
          • 56 Markings
            • 56.4 Marking of adjustable and nonadjustable features
          • 57 Service Equipment Markings
            • 57.1 Markings for service equipment in the United States
            • 57.2 Markings for service equipment in Canada
          • 58 Permanence of Marking
          • 59 Installation Test Procedures
          • 60 Transfer Switches for Fire Pump Service
        • TABLES
        • FIGURES
    • Annex A (Informative) Standards for Components
    • Annex B(Normative) References
    • ANNEX C(Normative)Bypass Transfer Switches
    • ANNEX D(Informative)French Translations of Markings