• The Protection of Telecommunication Lines and Equipment against Lightning Discharges
  • CHAPTER 1 – INTRODUCTION
    • 1. General
    • 2. Aims and limits of protection against lightning
    • 3. Definitions
      • 3.1 Thunderstorm day
      • 3.2 Isokeraunic line
      • 3.3 Impulse current
      • 3.4 Impulse and surge voltages
      • 3.5 Protective devices against surges
      • 3.6 Earthing network
      • 3.7 Diffusion impedance of an earthing network
      • 3.8 Transfer (or coupling) impedance of a metal cable sheath
      • 3.9 Quality factor of a metal-sheathed cable (resistivity factor for lightning voltages)
      • 3.10 Screening factor 1 of a metal cable sheath
  • CHAPTER 2 – ATMOSPHERIC DISCHARGES AND RESULTANT PHYSICAL PHENOMENA
    • 1. Electrical charge distribution and resultant physical phenomena
    • 2. Characteristics of discharge phenomena
    • 3. Frequency of lightning strokes
    • 4. Impulse breakdown of dielectrics
    • APPENDIX (to Chapter 2) – Waveform of impulses simulating lightning discharge currents
      • 1. Theoretical simulated impulse
      • 2. Practical simulated impulse
      • 3. Equivalent diagram of the lightning current circuit
  • CHAPTER 3 – THE ATMOSPHERIC ELECTRIC FIELDS ASSOCIATED WITH THUNDERSTORMS AND LIGHTNING DISCHARGES AND THEIR EFFECTS
    • 1. General
      • 1.1 Factors affecting the voltage in an overhead line conductor
    • 2. Electric field strength in the atmosphere
      • 2.1 Field when there is no lightning 1
      • 2.2 Field when lightning occurs
    • 3. Voltages in a horizontal, overhead conductor
      • 3.1 Lightning discharges to earth within about 3 km of a conductor and assuming a perfectly conducting earth
      • 3.2 Lightning discharges to earth within about 3 km of a conductor, when the earth resistance is not zero
      • 3.3 Lightning discharges more than 3 km away from a conductor and cloud discharges
    • 4. Effects produced in the ground by lightning strokes
    • 5. Other effects caused by lightning discharges
      • 5.1 Effects on metal conductors
      • 5.2 Effects on non-conducting material
    • APPENDIX (to Chapter 3) – Critical distance from the point of impact for cables with an insulating covering
  • CHAPTER 4 – THE EFFECTS OF LIGHTNING DISCHARGES TO OVERHEAD AND UNDERGROUND TELECOMMUNICATION LINES
    • 1. Lightning strokes which terminate on an overhead route
      • 1.1 The propagation and reflection of lightning surges and the effects on a multi-pair overhead route
      • 1.2 The effects on aerial cables
    • 2. Lightning strokes which terminate in the vicinity of a buried telecommunication cable
      • 2.1 Effects on cables with metal sheaths
      • 2.2 Effects on cables with an insulating covering over the metal sheath
      • 2.3 Effects on cables with non-metallic sheaths
      • 2.4 Effects on cables connected to overhead lines
      • 2.5 Effects on cables to mountain top radio stations
      • 2.6 Effects on cable conductors and associated insulation
    • APPENDIX 1 (to Chapter 4) – Propagation of lightning currents on an overhead line
    • APPENDIX 2 (to Chapter 4) – Simplified formula for the impulse voltage between conductors and metal sheath at the point of entry of the lightning current
  • CHAPTER 5 – PROTECTIVE DEVICES
    • 1. General
    • 2. Types of lightning protectors
      • 2.1 Air gap protectors
      • 2.2 Gas-filled protectors
    • 3. Junction diodes
    • 4. Fuses
    • 5. Coupling coils
    • 6. Choke coils in series
    • 7. Transverse protectors
    • 8. Forward protectors
    • 9. Shields or guards
      • 9.1 Shield wires placed above an open-wire line
      • 9.2 Shield-wires above buried cables
    • 10. Iron pipes (for underground cables)
    • 11. Cables of special design
      • 11.1 Transfer impedance of the metallic sheath
      • 11.2 Insulation of the conductors
      • 11.3 Quality factor
      • 11.4 Equipments connected to cables of special design
    • 12. Code, construction and protection of plastic-sheathed or plastic-covered cables
    • 13. Specification for transformers with high dielectric strength used in conjunction with cables of special design
    • APPENDIX (to Chapter 5) – Calculation of cable characteristics with increased resistance to lightning currents and with layer sheaths
      • 1. General
      • 2. Calculation (see Figure 5.3)
      • 3. Composition of the cable
      • 4. Example of calculation
      • 5. Cable behaviour in practice
      • 6. Use of cables with layer sheath in case of induced voltages