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TOC
1.1 GENERAL
1.2 APPLICATION
1.3 DEFINITIONS
1.4 REFERENCED DOCUMENTS
1.5 DESCRIPTION
1.5.1 Facility Ground System
1.5.2 Grounding and Power Distribution Systems
1.5.3 Electrical Noise in Communications Systems
1.6 BONDING, SHIELDING, AND GROUNDING RELATIONSHIP
1.7 GROUNDING SAFETY PRACTICES
CHAPTER 2 – EARTHING AND EARTH ELECTRODE SUBSYSTEM
2.1 OBJECTIVES
2.1.1 Lightning Discharge
2.1.2 Fault Protection
2.1.3 Noise Reduction
2.1.4 Summary of Requirements
2.2 RESISTANCE REQUIREMENTS
2.2.1 General
2.2.2 Resistance to Earth
2.2.3 Lightning Requirements
2.3 SOIL RESISTIVITY
2.3.1 General
2.3.2 Typical Resistivity Ranges
2.3.3 Environmental Effects
2.4 MEASUREMENT OF SOIL RESISTIVITY
2.4.1 General
2.4.2 Measurement Techniques
2.4.2.1 One-Electrode Method
2.4.2.2 Four-Terminal Method
2.5 TYPES OF EARTH ELECTRODE SUBSYSTEMS
2.5.1 General
2.5.2 Ground Rods
2.5.3 Buried Horizontal Conductors
2.5.4 Grids
2.5.5 Plates
2.5.6 Metal Frameworks of Buildings
2.5.7 Water Pipes
2.5.8 Incidental Metals
2.5.9 Well Casings
2.6 RESISTANCE PROPERTIES
2.6.1 Simple Isolated Electrodes
2.6.1.1 Driven Rod
2.6.1.2 Other Commonly Used Electrodes
2.6.2 Resistance of Multiple Electrodes
2.6.2.1 Two Vertical Rods in Parallel
2.6.2.2 Square Array of Vertical Rods
2.6.2.3 Horizontal Grid (Mesh)
2.6.2.4 Vertical Rods Connected by a Grid
2.6.3 Transient Impedance of Electrodes
2.6.4 Effects of Nonhomogeneous (Layered) Earth
2.6.4.1 Hemispherical Electrode
2.6.4.2 Vertical Rod
2.6.4.3 Grids
2.7 MEASUREMENT OF RESISTANCE-TO-EARTH OF ELECTRODES
2.7.1 Introduction
2.7.2 Fall-of-Potential Method
2.7.2.1 Probe Spacing
2.7.2.2 Extensive Electrode Subsystems
2.7.2.3 Test Equipments
2.7.3 Three-Point (Triangulation) Method
2.8 OTHER CONSIDERATIONS
2.8.1 Surface Voltages Above Earth Electrodes
2.8.1.1 Step Voltage Safety Limit
2.8.1.2 Step Voltages for Practical Electrodes
2.8.1.2.1 Flush Vertical Rod
2.8.1.2.2 Buried Vertical Rod
2.8.1.2.3 Buried Horizontal Grid
2.8.1.3 Minimizing Step Voltage
2.8.2 Heating of Electrodes
2.8.2.1 Steady State Current
2.8.2.2 Transient Current
2.8.2.3 Minimum Electrode Size
2.9 ELECTRODE ENHANCEMENT
2.9.1 Introduction
2.9.2 Water Retention
2.9.3 Chemical Salting
2.9.4 Electrode Encasement
2.9.5 Salting Methods
2.10 CATHODIC PROTECTION
2.10.1 Introduction
2.10.2 Protection Techniques
2.10.3 Sacrifical Anodes
2.10.4 Corrosive Atmospheres
2.11 GROUNDING IN ARCTIC REGIONS
2.11.1 Soil Resistivity
2.11.2 Improving Electrical Grounding in Frozen Soils
2.11.2.1 Electrode Resistance
2.11.2.2 Installation and Measurement Methods
CHAPTER 3 – LIGHTNING PROTECTION SUBSYSTEM
3.1 THE PHENOMENON OF LIGHTNING
3.2 DEVELOPMENT OF A LIGHTNING FLASH
3.3 INFLUENCE OF STRUCTURE HEIGHT
3.4 STRIKE LIKELIHOOD
3.5 ATTRACTIVE AREA
3.5.1 Structures Less Than 100 Meters High
3.5.2 Cone of Protection
3.6 LIGHTNING EFFECTS
3.6.1 Flash Parameters
3.6.2 Mechanical and Thermal Effects
3.6.3 Electrical Effects
3.6.3.1 Conductor Impedance Effects
3.6.3.2 Induced Voltage Effects
3.6.3.3 Capacitively-Coupled Voltage
3.6.3.4 Earth Resistance
3.7 BASIC PROTECTION REQUIREMENTS
3.8 DETERMINING THE NEED FOR PROTECTION
3.8.1 Strike Likelihood
3.8.2 Type of Construction
3.8.3 Criticalness to System Mission
3.9 APPLICABLE CODES
CHAPTER 4 -FAULT PROTECTION SUBSYSTEM
4.1 FAULT PROTECTION
4.1.1 Power System Faults
4.1.2 Ground-Fault-Circuit-Interrupter (GFCI)
4.2 EARTH CONNECTION
4.3 AC POWER LINE GROUND
4.4 TEST EQUIPMENT
CHAPTER 5 – GROUNDING OF SIGNAL REFERENCE SUBSYSTEM
5.1 INTRODUCTION
5.2 CONDUCTOR CONSIDERATIONS.
5.2.1 Direct Current Resistance
5.2.2 Alternating Current Impedance
5.2.2.1 Skin Effect.
5.2.2.2 AC Resistance
5.2.2.3 Reactanc e
5.2.2.4 Proximity Effect
5.2.3 Resistance Properties vs Impedance Properties
5.2.4 Effects of Geometry
5.2.4.1 Stranded Cables
5.2.4.2 Rectangular Conductors
5.2.4.3 Tubular Conductors
5.2.4.4 Structural Steel Members
5.3 SIGNAL REFERENCE SUBSYSTEM NETWORK CONFIGURATIONS
5.3.1 Floating Ground
5.3.2 Single-Point Ground (for Lower Frequencies)
5.3.3 Multipoint Ground (for Higher Frequencies)
5.3.4 Floating System
5.4 SITE APPLICATIONS
5.4.1 Lower Frequency Network
5.4.2 Higher Frequency Network
5.4.3 Frequency Limits
CHAPTER 6 – INTERFERENCE COUPLING AND REDUCTION
6.1 INTRODUCTION
6.2 COUPLING MECHANISMS
6.2.1 Conductive Coupling
6.2.2 Free-Space Coupling
6.2.2.1 Near-Field Coupling
6.2.2.2 Inductive Coupling
6.2.2.3 Capacitive Coupling
6.2.2.4 Far-Field Coupling
6.3 COMMON-MODE NOISE
6.3.1 Basic Theory of Common-Mode Coupling
6.3.2 Differential Amplifier
6.4 MINIMIZATION TECHNIQUES
6.4.1 Reduction of Coupling
6.4.1.1 Reference Plane Impedance Minimization
6.4.1.2 Spatial Separation
6.4.1.3 Reduction of Circuit Loop Area
6.4.1.4 Shielding
6.4.1.5 Balanced Lines
6.4.2 Alternate Methods
6.5 FACILITY AND EQUIPMENT REQUIREMENTS
CHAPTER 7 – BONDING
7.1 DEFINITION OF BONDING
7.2 PURPOSES OF BONDING
7.3 RESISTANCE CRITERIA
7.4 DIRECT BONDS
7.4.1 Contact Resistance
7.4.1.1 Surface Contaminants
7.4.1.2 Surface Hardness
7.4.1.3 Contact Pressure
7.4.1.4 Bond Area
7.4.2 Direct Bonding Techniques
7.4.2.1 Welding
7.4.2.2 Brazing
7.4.2.3 Soft Solder
7.4.2.4 Bolts
7.4.2.5 Rivets
7.4.2.6 Conductive Adhesive
7.4.2.7 Comparison of Techniques
7.5 INDIRECT BONDS
7.5.1 Resistance
7.5.2 Frequency Effects
7.5.2.1 Skin Effect
7.5.2.2 Bond Reactance
7.5.2.3 Stray Capacitance
7.6 SURFACE PREPARATION
7.6.1 Solid Materials
7.6.2 Organic Compounds
7.6.3 Platings and Inorganic Finishes
7.6.4 Corrosion By-Products
7.7 COMPLETION OF THE BOND
7.8 BOND CORROSION
7.8.1 Chemical Basis of Corrosion
7.8.1.1 Electrochemical Series
7.8.1.2 Galvanic Series
7.8.2 Relative Area of Anodic Member
7.8.3 Protective Coatings
CHAPTER 8 – SHIELDING
8.1 FUNCTION OF AN ELECTROMAGNETIC SHIELD
8.2 BASIC SHIELDING THEORY
8.2.1 Oppositely Induced Fields
8.2.2 Transmission Line Analogy
8.2.3 Nonuniform Shielding
8.3 SHIELDING EFFECTIVENESS OF CONTINUOUS SINGLE-THICKNESS SHIELDS.
8.3.1 Absorption Loss
8.3.2 Reflection Loss
8.3.3 Re-Reflection Correction Factor
8.3.4 Total Shielding Effectiveness
8.3.4.1 Measured Data
8.4 SHIELDING EFFECTIVENESS OF OTHER SHIELDS
8.4.1 Multiple Solid Shields
8.4.2 Coatings and Thin-Film Shields
8.4.3 Screens and Perforated Metal Shields
8.5 SHIELD DISCONTINUITY EFFECTS (APERTURES)
8.5.1 Seams Without Gaskets
8.5.2 Seams With Gaskets
8.5.3 Penetration Holes
8.6 SELECTION OF SHIELDING MATERIALS
8.7 USE OF CONVENTIONAL BUILDING MATERIALS
8.7.1 Concrete
8.7.2 Reinforcing Steel (Rebar)
8.8 CABLE AND CONNECTOR SHIELDING
8.8.1 Cable Shields
8.8.2 Terminations and Connectors
8.9 SHIELDED ENCLOSURES (SCREEN ROOMS)
8.9.1 Demountable (Modular) Enclosures
8.9.2 Custom Built Rooms
8.9.3 Foil Room Liners
8.10 TESTING OF SHIELDS
8.10.1 Low Impedance Magnetic Field Testing Using Small Loops
8.10.2 Additional Test Methods
8.11 PERSONNEL PROTECTION SHIELDS
8.12 DETERMINATION OF SHIELDING REQUIREMENTS
8.12.1 Equipment Disturbances
8.12.2 Electromagnetic Environmental Survey
8.12.3 Equipment EMI Properties
8.13 SYSTEM DESIGN CONSIDERATIONS
CHAPTER 9 – PERSONNEL PROTECTION
9.1 ELECTRIC SHOCK
9.1.1 Levels of Electric Shock
9.1.2 Shock Prevention
9.2 STATIC ELECTRICITY
9.3 RADIO FREQUENCY (RF) RADIATION HAZARDS
9.4 LASER HAZARDS
9.5 X-RAY RADIATION
9.6 REFERENCES
CHAPTER 10 – NUCLEAR EMP EFFECTS
10.1 INTRODUCTION
10.2 EMP GENERATION
10.2.1 High-Altitude EMP (HEMP)
10.2.1.1 Early-Time HEMP
10.2.1.2 Late-Time HEMP (MHDEMP)
10.2.1.3 Intermediate-Time HEMP
10.2.2 Surface-Burst EMP
10.2.3 Other EMP Phenomena
10.2.4 Comparison With Lightning
10.3 HEMP INTERACTION WITH SYSTEMS
10.3.1 Current in Long Lines
10.3.1.1 Long Overhead Lines
10.3.1.2 Long Buried Lines
10.3.1.3 Vertical Structures
10.3.2 HEMP Interaction With Local Structure
10.3.2.1 Shields
10.3.2.2 Penetrating Conductors
10.3.2.3 Apertures
10.4 PROTECTION AGAINST HEMP
10.4.1 HEMP Barrier
10.4.1.1 Shield
10.4.1.2 Penetrating Conductors
10.4.1.3 Apertures
10.4.2 Allocation of Protection
10.4.2.1 Amount of Protection Needed
10.4.2.2 Where Protection is Applied
10.4.2.3 Terminal Protection Devices
10.4.2.4 Waveguide Penetration of Facility Shield
CHAPTER 11 – NOTES
11.1 SUBJECT TERM (KEY WORD) LISTING
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