176 pages | 104 B/W Illus.
Learn the theory behind grounding systems and bonding equipotential connections from a worldwide expert. Through mathematical analysis, comprehensive explanations and detailed figures, Analysis of Grounding and Bonding Systems explains the theory and the reasons behind basic ground electrodes (i.e., the sphere, the ground-rod, and the horizontal ground-wire), and more complex grounding systems (i.e., ground-grids), buried in uniform and non-uniform soils.
Through calculations and explanatory diagrams, this comprehensive guide provides code-complying solutions for the safety against electric shock provided by equipontential bonding connections between exposed conductive parts, such as equipment enclosures, and metalwork. Details on the calculation of step and touch voltages in different types of system grounding (i.e., TT, TN and IT) are provided, also with the aid of solved problems.
Readers will learn how to minimize hazardous interactions between grounding systems, cathodically protected pipelines, and heat networks. The analysis of the effectiveness of bonding systems against electric shock in the case of contact with electric vehicles during charge in the event of ground-faults, which is an upcoming issue challenging our safety, is included.
1. Grounding Systems and Safety
1.2 System ground
1.3 Protective and functional grounding.
1.4 Temporary ground.
1.5 Protective function of the ground grid
1.6 Ground-Fault currents
1.7 Electrical Safety-By-Design
1.7.1 Design of the ground-grid
1.8 Transferred potential from high-voltage systems to low-voltage systems
1.9 The Earth as the sole ground-fault current return path
1.10 Grounding and protective conductors as the ground-fault current return path.
1.11 Overhead ground wire of transmission line as the ground-fault current return path.
1.12 Medium-voltage systems grounded via neutral grounding resistors
2.1 The Ground Potential
2.2 Ground-resistance and Ground-impedance
2.3 Ground-electrodes connected in parallel
2.4 Ground-electrodes connected in series
2.5 Prospective Touch and Step Voltages
2.6 Resistance of the human body
2.7 Resistance-to-Ground of the human body
2.8 The Effective Touch Voltage
2.9 The Effective Step Voltage
2.10 Permissible values VTp of the effective touch voltage
2.10 Permissible values VSTp of the prospective touch voltage
2.11 Touch Currents
2.12 Interconnection of grounding systems
2.13 Separation of grounding systems
Ch. 3 Types of System Grounding and Safety Requirements
3.2 TT System Grounding
3.2.1 Faulty neutral conductor in TT systems
3.2.2 Electric shock hazard in TT systems in the event of line-to-PE short circuit
3.2.2 Factors affecting ground and touch potentials within buildings in TT systems
3.3 TN System Grounding
3.3.1 Interruption of the PE in TN-S systems
3.3.2 Protection against electric shock in TN-S systems
3.3.3 Fault-loop Impedance
18.104.22.168 Fault-loop resistance
22.214.171.124 Fault-loop reactance
3.3.4 The PEN conductor
3.3.5 Accidental interruption of the PEN conductor in TN-C-S systems
3.3.6 Prospective touch voltages in TN systems in ground-fault conditions
3.3.7 Prospective touch voltages in TN systems in fault-free conditions
3.3.8 Supplementary Equipotential Bonding Connections
3.4 IT system grounding
3.6 Sizing of protective conductors
3.6.1 Calculation of the k factor
3.7 Residual Current Devices and d.c. components of ground-fault current
Ch. 4 Analysis of Basic Ground-Electrodes
4.1 Spherical electrode buried in boundless and uniform medium
4.2 Principle of Images
4.3 Spherical electrode buried at depth h
4.3.1 The ground potential rise VG
4.3.2 Influence of the depth of burial on RG
4.3.3 Prospective touch and step voltages induced by spherical electrodes
4.4 Ground-wire embedded in boundless and uniform medium
4.5 Ground-wire buried at depth h
4.5.1 Ground potential
4.6 Ground-rod buried at depth h
4.6.1 Ground potentials
4.8 Principle of Images in multi-layered soils
4.8.1 Ground-rod in two-layer soil
Ch. 5 Analysis of Complex Grounding Systems
5.3 Square ground-grid
5.3.1 Ground-potential profiles
5.4 Square ground-grid with ground-rods at corners
5.4.1 Ground-potential profiles
5.5 Ground-grid with meshes of equal area
5.5.1 Ground-potential profiles
5.6 Ground-grid with meshes and ground-rods.
5.6.1 Ground-potential profiles
Ch. 6 Interferences Phenomena between ground-grids
6.2 Analysis of interferences between ground-grids
6.3 Transferred potentials
6.3.1 Pipes and rails
Ch. 7 Global Grounding System
7.2 Interconnection of grounding systems of substations
7.3 Proximity of grounding systems of substations
7.4 Quasi-equipotential region in GGSs
7.5 Identification of a Global Grounding System
Ch. 8 Grounding and Bonding Systems and interactions with cathodically protected pipelines
8.2 Ground-grids and interactions in normal operating conditions
8.3 Ground-grids and interactions in the event of low-voltage ground-faults
8.4 Ground-grids and interactions in the event of high-voltage ground-faults
8.5 Ground-grids and interactions in TT systems
Ch. 9 Grounding systems and interaction with heat networks
9.2 Electric conductivity of water
9.3 Insulating joints
9.2 Equivalent circuits in the event of ground-faults
Ch. 10 Bonding systems for Electric Road Vehicles
10.2 The Basic Protection of the EV during charge and in motoring mode
10.3 The Fault Protection of the EV in motoring mode.
10.4 The Fault Protection of the EV during charge.
10.5 Class II Chargers.
10.6 Extra-Low-Voltage Chargers