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| Introduction | |
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| General | |
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| Definitions | |
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| General | |
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| Over 600 Volts, Nominal | |
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| Requirements for Electrical Installations | |
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| General | |
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| 600 Volts, Nominal, or Less | |
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| Over 600 Volts, Nominal | |
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| Tunnel Installations Over 600 Volts, Nominal | |
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| Wiring and Protection | |
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| Use and Identification of Grounded Conductors | |
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| Branch Circuits | |
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| General Provisions | |
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| Branch-Circuit Ratings | |
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| Required Outlets | |
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| Feeders | |
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| Branch-Circuit, Feeder, and Service Calculations | |
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| General | |
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| Feeders and Services | |
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| Optional Calculations for Computing Feeder and Service Loads | |
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| Method for Computing Farm Loads | |
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| Outside Branch Circuits and Feeders | |
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| General | |
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| More than One Building or Other Structure | |
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| Over 600 Volts | |
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| Services | |
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| General | |
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| Overhead Service-Drop Conductors | |
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| Underground Service-Lateral Conductors | |
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| Service-Entrance Conductors | |
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| Service Equipment -- General | |
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| Service Equipment -- Disconnecting Means | |
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| Service Equipment -- Overcurrent Protection | |
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| Services Exceeding 600 Volts, Nominal | |
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| Overcurrent Protection | |
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| General | |
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| Location | |
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| Enclosures | |
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| Disconnecting and Guarding | |
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| Plug Fuses, Fuseholders, and Adapters | |
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| Cartridge Fuses and Fuseholders | |
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| Circuit Breakers | |
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| Supervised Industrial Installations | |
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| Overcurrent Protection Over 600 Volts, Nominal | |
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| Grounding | |
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| General | |
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| Circuit and System Grounding | |
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| Grounding Electrode System and Grounding electrode Conductor | |
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| Enclosure, Raceway, and Service Cable Grounding | |
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| Bonding | |
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| Equipment Grounding and Equipment Grounding Conductors | |
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| Methods of Equipment Grounding | |
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| Direct-Current Systems | |
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| Instruments, Meters, and Relays | |
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| Grounding of Systems and Circuits of 1 kV and Over (High Voltage) | |
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| Surge Arresters | |
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| General | |
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| Installation | |
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| Connecting Surge Arresters | |
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| Wiring Methods and Materials | |
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| Wiring Methods | |
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| General Requirements | |
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| Requirements for Over 600 Volts, Nominal | |
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| Temporary Wiring | |
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| Conductors for General Wiring | |
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| Cable Trays | |
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| Open Wiring on Insulators | |
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| Messenger Supported Wiring | |
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| Concealed Knob-and-Tube Wiring | |
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| Integrated Gas Spacer Cable | |
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| General | |
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| Installation | |
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| Construction Specifications | |
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| Medium Voltage Cable | |
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| Flat Conductor Cable | |
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| General | |
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| Installation | |
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| Construction | |
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| Mineral-Insulated, Metal-Sheathed Cable | |
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| General | |
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| Installation | |
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| Construction Specifications | |
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| Electrical Nonmetallic Tubing | |
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| General | |
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| Installation | |
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| Construction Specifications | |
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| Armored Cable | |
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| General | |
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| Installation | |
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| Construction Specifications | |
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| Metal-Clad Cable | |
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| General | |
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| Installation | |
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| Construction Specifications | |
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| Nonmetallic-Sheathed Cable | |
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| General | |
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| Installation | |
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| Construction Specifications | |
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| Service-Entrance Cable | |
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| Underground Feeder and Branch-Circuit Cable | |
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| Power and Control Tray Cable | |
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| Nonmetallic Extensions | |
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| Nonmetallic Underground Conduit with Connectors | |
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| General | |
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| Installation | |
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| Construction | |
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| Intermediate Metal Conduit | |
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| General | |
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| Installation | |
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| Construction Specifications | |
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| Rigid Metal Conduit | |
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| General | |
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| Installation | |
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| Construction Specifications | |
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| Rigid Nonmetallic Conduit | |
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| Installations | |
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| Construction Specifications | |
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| Electrical Metallic Tubing | |
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| General | |
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| Installation | |
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| Construction Specifications | |
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| Flexible Metallic Tubing | |
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| General | |
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| Construction and Installation | |
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| Flexible Metal Conduit | |
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| General | |
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| Installation | |
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| Liquidtight Flexible Metal Conduit and Liquidtight Flexible Nonmentallic Conduit | |
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| Liquidtight Flexible Metal Conduit | |
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| Liquidtight Flexible Nonmetallic Conduit | |
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| Surface Metal Raceways and Surface Nonmetallic Raceways | |
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| Surface Metal Raceways | |
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| Surface Nometallic Raceways | |
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| Strut-Type Channel Raceway | |
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| Multioutlet Assembly | |
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| Underfloor Raceways | |
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| Cellular Metal Floor Raceways | |
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| Installation | |
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| Construction Specifications | |
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| Cellular Concrete Floor Raceways | |
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| Metal Wireways and Nonmetallic Wireways | |
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| Metal Wireways | |
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| Nonmetallic Wireways | |
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| Flat Cable Assemblies | |
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| Busways | |
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| General Requirements | |
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| Requirements for Over 600 Volts, Nominal | |
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| Cablebus | |
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| Outlet, Device, Pull and Junction Boxes, Conduit Bodies and Fittings | |
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| Scope and General | |
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| Installation | |
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| Construction Specifications | |
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| Manholes and Other Electric Enclosures Intended for Personnel Entry | |
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| Pull and Junction Boxes for Use on Systems Over 600 Volts, Nominal | |
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| Cabinets, Cutout Boxes, and Meter Socket Enclosures | |
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| Installation | |
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| Construction Specifications | |
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| Auxiliary Gutters | |
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| Switches | |
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| Installation | |
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| Construction Specifications | |
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| Switchboards and Panelboards | |
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| General | |
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| Switchboards | |
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| Panelboards | |
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| Construction Specifications | |
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| Equipment for General Use | |
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| Flexible Cords and Cables | |
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| General | |
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| Construction Specifications | |
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| Portable Cables Over 600 Volts, Nominal | |
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| Fixture Wires | |
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| Lighting Fixtures, Lampholders, Lamps, and Receptacles | |
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| General | |
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| Fixture Locations | |
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| Provisions at Fixture Outlet Boxes, Canopies, and Pans | |
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| Fixture Supports | |
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| Grounding | |
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| Wiring of Fixtures | |
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| Construction of Fixtures | |
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| Installation of Lampholders | |
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| Construction of Lampholders | |
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| Lamps and Auxiliary Equipment | |
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| Receptacles, Cord Connectors, and Attachment Plugs (Caps) | |
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| Special Provisions for Flush and Recessed Fixtures | |
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| Construction of Flush and Recessed Fixtures | |
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| Special Provisions for Electric-Discharge Lighting Systems of 1000 Volts or Less | |
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| Special Provisions for Electric-Discharge Lighting Systems of More Than 100 Volts | |
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| Lighting Track | |
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| Lighting Systems Operating at 30 Volts or Less | |
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| Appliances | |
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| General | |
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| Installation | |
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| Disconnecting Means | |
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| Construction | |
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| Marking | |
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| Fixed Electric Space-Heating Equipment | |
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| General | |
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| Installation | |
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| Control and Protection of Fixed Electric Space-Heating Equipment | |
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| Marking of Heating Equipment | |
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| Electric Space-Heating Cables | |
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| Duct Heaters | |
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| Resistance-Type Boilers | |
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| Electrode-Type Boilers | |
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| Electric Radiant Heating Panels and Heating Panel Sets | |
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| Fixed Outdoor Electric Deicing and Snow-Melting Equipment | |
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| General | |
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| Installation | |
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| Resistance Heating Elements | |
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| Impedance Heating | |
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| Skin-Effect Heating | |
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| Control and Protection | |
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| Fixed Electric Heating Equipment for Pipelines and Vessels | |
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| General | |
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| Installation | |
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| Resistance Rating Elements | |
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| Induction Heating | |
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| Skin-Effect Heating | |
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| Control and Protection | |
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| Motors, Motor Circuits, and Controllers | |
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| General | |
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| Motor Circuit Conductors | |
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| Motor and Branch-Circuit Overload Protection | |
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| Motor Branch-Circuit Short-Circuit and Ground-Fault Protection | |
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| Motor Feeder Short-Circuit and Ground-Fault Protection | |
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| Motor Control Circuits | |
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| Motor Controllers | |
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| Motor Control Centers | |
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| Disconnecting Means | |
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| Over 600 Volts, Nominal | |
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| Protection of Live Parts -- All Voltages | |
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| Grounding -- All Voltages | |
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| Tables | |
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| Air-Conditioning and Refrigeration Equipment | |
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| General | |
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| Disconnecting Means | |
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| Branch-Circuit Short-Circuit and Ground-Fault Protection | |
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| Branch-Circuit Conductors | |
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| Controllers for Motor-Compressors | |
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| Motor-Compressor and Branch-Circuit Overload Protection | |
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| Provisions for Room Air Conditioners | |
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| Generators | |
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| Transformers and Transformer Vaults (Including Secondary Ties) | |
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| General Provisions | |
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| Specific Provisions Applicable to Different Types of Transformers | |
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| Transformer Vaults | |
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| Phase Converters | |
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| General | |
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| Specific Provisions Applicable to Different Types of Transformers | |
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| Capacitors | |
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| 600 Volts, Nominal, and Under | |
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| Over 600 Volts, Nominal | |
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| Resistors and Reactors | |
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| 600 Volts, Nominal, and Under | |
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| Over 600 Volts, Nominal | |
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| Storage Batteries | |
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| Equipment, Over 600 Volts, Nominal | |
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| General | |
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| Equipment -- Specific Provisions | |
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| Equipment -- Metal-Enclosed Power Switchgear and Industrial Control Assemblies | |
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| Mobile and Portable Equipment | |
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| Electrode-Type Boilers | |
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| Special Occupancies | |
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| Hazardous (Classified) Locations, Classes I, II, and III, Divisions 1 and 2 | |
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| Class I Locations | |
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| Class II Locations | |
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| Class III Locations | |
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| Intrinsically Safe Systems | |
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| Class I, Zone 0, 1, and 2 Locations | |
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| Hazardous (Classified) Locations -- Specific | |
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| Commercial Garages, Repair and Storage | |
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| Aircraft Hangars | |
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| Gasoline Dispensing and Service Stations | |
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| Bulk Storage Plants | |
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| Spray Application, Dipping, and Coating Processes | |
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| Health Care Facilities | |
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| General | |
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| Wiring and Protection | |
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| Essential Electrical System | |
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| Inhaiation Anesthetizing Locations | |
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| X-Ray Installations | |
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| Communications, Signaling Systems, Data Systems, Fire Alarm Systems, and Systems Less than 120 Volts, Nominal | |
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| Isolated Power Systems | |
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| Places of Assembly | |
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| Theaters, Audience Areas of Motion Picture and Television Studios, and Similar Locations | |
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| General | |
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| Fixed Stage Switchboards | |
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| Fixed Stage Equipment Other than Switchboards | |
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| Portable Switchboards on Stage | |
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| Portable Stage Equipment Other than Switchboards | |
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| Dressing Rooms | |
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| Grounding | |
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| Carnivals, Circuses, Fairs, and Similar Events | |
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| General Requirements | |
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| Installation | |
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| Grounding and Bonding | |
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| Disconnecting Means | |
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| Attractions Utilizing Pools, Fountains, and Similar Installations with Contained Volumes of Water | |
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| Motion Picture and Television Studios and Similar Locations | |
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| General | |
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| Stage or Set | |
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| Dressing Rooms | |
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| Viewing, Cutting, and Patching Tables | |
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| Cellulose Nitrate Film Storage Vaults | |
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| Substations | |
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| Separately Derived Systems with 60 Volts to Ground | |
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| Motion Picture Projectors | |
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| General | |
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| Definitions | |
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| Equipment and Projectors of the Professional Type | |
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| Nonprofessional Projectors | |
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| Audio Signal Processing, Amplification, and Reproduction Equipment | |
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| Manufactured Building | |
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| General | |
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| Agricultural Buildings | |
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| Mobile Homes, Manufactured Homes, and Mobile Home Parks | |
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| General | |
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| Mobile Homes | |
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| Services and Feeders | |
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| Recreational Vehicles and Recreational Vehicle Parks | |
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| General | |
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| Low-Voltage Systems | |
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| Combination Electrical Systems | |
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| Other Power Sources | |
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| Norminal 120-Volt or 120/240-Volt Systems | |
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| Factory Tests | |
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| Recreational Vehicle Parks | |
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| Park Trailers | |
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| General | |
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| Low-Voltage Systems | |
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| Combination Electrical Systems | |
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| Nominal 120-Volt or 120/240-Volt Systems | |
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| Factory Tests | |
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| Floating Buildings | |
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| General | |
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| Services and Feeders | |
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| Grounding | |
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| Marinas and Boatyards | |
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| Special Equipment | |
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| Electric Signs and Outline Lighting | |
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| General | |
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| Field-Installed Skeleton Tubing | |
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| Manufactured Wiring Systems | |
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| Office Furnishings (Consisting of Lighting Accessories and Wired Partitions) | |
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| Cranes and Hoists | |
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| General | |
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| Wiring | |
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| Contact Conductors | |
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| Disconnecting Means | |
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| Overcurrent Protection | |
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| Control | |
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| Grounding | |
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| Elevators, Dumbwaiters, Escalators, Moving Walks, Wheelchair Lifts, and Stairway Chair Lifts | |
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| General | |
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| Conductors | |
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| Wiring | |
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| Installation of Conductors | |
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| Traveling Cables | |
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| Disconnecting Means and Control | |
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| Overcurrent Protection | |
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| Machine Room | |
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| Grounding | |
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| Emergency and Standby Power Systems | |
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| Electric Vehicle Charging System Equipment | |
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| General | |
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| Wiring Methods | |
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| Equipment Construction | |
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| Control and Protection | |
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| Electric Vehicle Supply Equipment Locations | |
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| Electric Welders | |
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| General | |
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| Are Welders | |
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| Resistance Welders | |
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| Welding Cable | |
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| Audio Signal Processing Araplification, and Reproduction Equipment | |
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| General | |
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| Permanent Audio System Installations | |
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| Portable and Temporary Audio System Installations | |
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| Information Technology Equipment | |
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| Pipe Organs | |
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| X-Ray Equipment | |
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| General | |
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| Control | |
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| Transformers and Capacitors | |
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| Guarding and Grounding | |
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| Induction and Dielectric Heating Equipment | |
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| General | |
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| Guarding, Grounding, and Labeling | |
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| Motor-Generator Equipment | |
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| Equipment Other than Motor-Generators | |
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| Electrolytic Cells | |
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| Electroplating | |
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| Industrial Machinery | |
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| Electrically Driven or Controlled Irrigation Machines | |
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| General | |
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| Center Pivot Irrigation Machines | |
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| Swimming Pools, Fountains, and Similar Installations | |
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| General | |
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| Permanently Installed Pools | |
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| Storable Pools | |
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| Spas and Hot Tubs | |
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| Fountains | |
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| Pools and Tubs for Therapeutic Use | |
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| Hydromassage Bathtubs | |
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| Integrated Electrical Systems | |
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| General | |
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| Orderly Shutdown | |
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| Solar Photovoltaic Systems | |
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| General | |
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| Circuit Requirements | |
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| Disconnecting Means | |
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| Wiring Methods | |
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| Grounding | |
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| Marking | |
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| Connection to Other Sources | |
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| Storage Batteries | |
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| Systems Over 600 Volts | |
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| Fire Pumps | |
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| Special Conditions | |
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| Emergency Systems | |
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| General | |
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| Circuit Wiring | |
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| Sources of Power | |
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| Emergency System Circuits for Lighting and Power | |
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| Control -- Emergency Lighting Circuits | |
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| Overcurrent Protection | |
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| Legally Required Standby Systems | |
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| General | |
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| Circuit Wiring | |
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| Sources of Power | |
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| |
| Overcurrent Protection | |
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| Optional Standby Systems | |
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| General | |
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| Circuit Wiring | |
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| Interconnected Electrical Power Production Sources | |
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| |
| Circuits and Equipment Operating at Less than 50 Volts | |
| |
| |
| Class 1, Class 2, and Class 3 Remote-Control, Signaling, and Power-Limited Circuits | |
| |
| |
| General | |
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| |
| Class 1 Circuits | |
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| Class 2 and Class 3 Circuits | |
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| |
| Instrumentation Tray Cable: Type ITC | |
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| |
| Fire Alarm Systems | |
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| General | |
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| Nonpower-Limited Fire Alarm (NPLFA) Circuits | |
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| Power-Limited Fire Alarm (PLFA) Circuits | |
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| Optical Fiber Cables and Raceways | |
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| General | |
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| Protection | |
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| Cables Within Buildings | |
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| Closed-Loop and Programmed Power Distribution | |
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| Communications Systems | |
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| Communications Circuits | |
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| General | |
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| Conductors Outside and Entering Buildings | |
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| Protection | |
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| Grounding Methods | |
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| Communications Wires and Cables Within Buildings | |
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| Radio and Television Equipment | |
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| General | |
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| Receiving Equipment -- Antenna Systems | |
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| Amateur Transmitting and Receiving Stations -- Antenna Systems | |
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| Interior Installation -- Transmitting Stations | |
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| Community Antenna Television and Radio Distribution Systems | |
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| General | |
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| Cables Outside and Entering Buildings | |
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| Protection | |
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| Grounding Methods | |
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| Cables Within Buildings | |
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| Network-Powered Broadband Communications Systems | |
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| General | |
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| Cables Outside and Entering Buildings | |
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| Protection | |
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| Grounding Methods | |
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| Network-Powered Broadband Communications Systems Wiring Methods Within Buildings | |
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| Tables | |
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| Percent of Cross Section of Conduit and Tubing for Conductors | |
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| Dimensions and Percent Area of Conduit and Tubing | |
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| Dimensions of Insulated Conductors and Fixture Wires | |
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| Compact Aluminum Building Wire Nominal Dimensions and Areas | |
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| Conductor Properties | |
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| Alternating-Current Resistance and Reactance for 600-Volt Cables, 3-Phase, 60 Hz, 75[ch]C (167[ch]F) -- Three Single Conductors in Conduit | |
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| Class 2 and Class 3 Alternating-Current Power Source Limitations | |
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| Class 2 and Class 3 Direct-Current Power Source Limitations | |
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| PLFA Alternating-Current Power Source Limitations | |
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| PLFA Direct-Current Power Source Limitations | |
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| Appendix A | |
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| Appendix B | |
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| Appendix C | |
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| Appendix D | |
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| Appendix E | |
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| Index | |