Principles of Electrical Safety.pdf
Principles of Electrical Safety discusses current issues in electrical safety, which are accompanied by series' of practical applications that can be used by practicing professionals, graduate students, and researchers. . * Provides extensive introductions to important topics in electrical safety * Comprehensive overview of inductance, resistance, and capacitance as applied to the human body * Serves as a preparatory guide for today's practicing engineers
Peter E. Sutherland serves as lead consultant at GE Energy Services, in Schenectady, New York. He has a PhD in Electric Power Engineering from Rensselaer Polytechnic Institute. He is a well-respected industry expert who has taught several courses on the topic. He is a fellow of IEEE.
Preface 1 Introduction 2 Mathematics used in Electromagnetism 2.1 Introduction 2.2 Numbers 2.3 Mathematical Operations with Vectors 2.4 Calculus with Vectors -- The Gradient 2.5 Divergence, Curl and Stokes' Theorem 2.6 Maxwell's Equations 3 Electrical Safety Aspects of the Resistance Property of Materials 3.1 Introduction 3.2 Hazards Caused by Electrical Resistance 3.3 Resistance and Conductance 3.4 Example - trunk of a human body 3.5 Example - limb of a human body 3.6 Power and Energy Flow 3.7 Sheet Resistivity 3.8 Example - square of dry skin 3.9 Spreading Resistance 3.10 Example - circle of dry skin 3.11 Particle Conductivity 3.12 Examples -- Potassium, Sodium and Chlorine Ions 3.13 Cable Resistance 4 Capacitance Phenomena 4.1 Fundamentals of Capacitance 4.2 Capacitance and Permittivity 4.3 Capacitance in Electrical Circuits 4.4 Capacitance of Body Parts 4.5 Electrical Hazards of Capacitance 5 Inductance Phenomena 5.1 Inductance in electrical theory 5.2 Inductance of Wires 5.3 Example -- Inductance of a Conductor 5.4 Example -- Inductance of Trunk and Limb 5.5 Inductors or Reactors 5.6 Skin Effect 5.7 Cable Inductance 5.8 Surge impedance 5.9 Bus Bar Impedance Calculations 6 Circuit model of human body 6.1 Calculation of Electrical Shock Using Circuit Model Of Body 6.2 Frequency Response Of The Human Body 7 Effect of Current on the Human Body 7.1 Introduction to Electrical Shock 7.2 Human and Animal Sensitivities to Electric Current 7.3 Human Body Impedance 7.4 Effects of Various Exposure Conditions 7.5 Current Paths through the Body 7.6 Human Response to Electrical Shock Varies with Exposure Conditions, Current Magnitude and Duration 7.7 Medical imaging and simulations 8 Fundamentals of Ground Grid Design 8.1 Introduction to Ground Grid Design 8.2 Summary of Ground Grid Design Procedures 8.3 Example Design from IEEE Standard 80 9 Safety Aspects of Ground Grid Operation and maintenance 9.1 Introduction 9.2 Effects of High Fault Currents 9.3 Reduction in electrical safety: Increased step and touch potentials 9.4 Damage or failure of grounding equipment 9.5 Recommendations 10 Grounding of Distribution Systems 10.1 Stray Currents in Distribution Systems 10.2 Three Phase Multigrounded Neutral Distribution Line 10.3 Secondary systems: 120/240V Single Phase 10.4 Remediation of Stray Current Problems 10.5 Grounding and Overvoltages in Distribution Systems 10.6 High Resistance Grounding of Distribution Systems 11 Arc Flash Hazard Analysis 11.1 Introduction to Arc Flash Hazards 11.2 Factors affecting the severity of arc flash hazards 11.3 Example Arc Flash Calculations 11.4 Remediation of Arc Flash Hazards 11.5 Coordination of Low Voltage Breaker Instantaneous Trips for Arc Flash Hazard Reduction 11.6 Low voltage transformer secondary arc flash protection using fuses 12 Effect of high fault currents on protection and metering 12.1 Introduction 12.2 Current transformer saturation 12.3 Saturation of Low Ratio CTs 12.3 Effect of high fault currents on coordination 12.4 Effect of high fault currents on coordination 12.5 Protective relay ratings and settings 12.6 Effects of Fault Currents on Protective Relays 12.7 Methods for upgrading protection systems 13 Effects of High Fault Currents on Circuit Breakers 13.1 Insufficient Interrupting Capability 13.2 Air Circuit Breakers 13.3 Vacuum Circuit Breakers 13.4 SF6 Circuit Breakers 13.5 Loss of Interruption Medium 13.6 Interrupting ratings of switching devices. 13.7 Circuit Breakers 13.8 Fuses 13.9 Case Studies 13.10 Low Voltage Circuit Breakers 13.11 Testing of Low Voltage Circuit Breakers 13.12 Testing of High Voltage Circuit Breakers 14 Mechanical forces and Thermal Effects in substation equipment due to high fault currents 14.1 Introduction 14.2 Definitions 14.3 Short circuit mechanical forces on rigid bus bars 14.4 Short circuit thermal effects 14.5 Flexible Conductor Buses 14.6 Force Safety Devices 14.7 Substation Cable and Conductor Systems 14.8 Distribution line conductor motion 14.9 Effects of High Fault Currents on Substation Insulators 14.10 Effects of High Fault Currents on Gas Insulated Substations (GIS) 15 Effect of High Fault Currents on Transmission Lines 15.1 Introduction 15.2 Effect of High Fault Current on Non-Ceramic Insulators (NCI) 15.3 Conductor Motion due to Fault Currents 15.4 Calculation of fault current motion for horizontally spaced conductors 15.5 Effect of conductor shape 15.6 Conductor equations of motion 15.7 Effect of conductor stretch 15.8 Calculation of fault current motion for vertically spaced conductors 15.9 Calculation procedure 15.10 Calculation of tension change with motion 15.11 Calculation of mechanical loading on phase-to-phase spacers 15.12 Effect of Bundle Pinch on Conductors and Spacers 16 Lightning and Surge Protection 16.1 Surge Voltage Sources and Waveshapes 16.2 Surge Propagation, Refraction and Reflection 16.3 Insulation Withstand Characteristics and Protection 16.4 Surge Arrester Characteristics 16.5 Surge Arrester Application References