Introduction
1 Scope
2 Normative references
3 Terms and definitions
to continue
4 Description of technologies
  4.1 Voltage-limiting devices
      4.1.1 Clamping-type
      4.1.2 Switching-type
  4.2 Current-limiting devices
      4.2.1 Current-interrupting type
      4.2.2 Current-reducing type
      4.2.3 Current-diverting type
5 Parameters for selection of SPDs and appropriate
  tests from EN 61643-21
  5.1 Controlled and uncontrolled environments
      5.1.1 Controlled environments
      5.1.2 Uncontrolled environments
  5.2 SPD parameters that may affect normal system operation
6 Risk management
  6.1 Risk analysis
  6.2 Risk identification
  6.3 Risk treatment
7 Application of SPDs
  7.1 General
to continue
  7.2 Coupling mechanisms
  7.3 Application, selection and installation of surge
      protective devices (SPDs)
      7.3.1 Application requirements for SPDs
      7.3.2 SPD installation cabling considerations
8 Multiservice surge protective devices
9 Coordination of SPDs/ITE
Annex A (informative) Voltage-limiting devices
      A.1 Voltage-clamping devices
          A.1.1 Metal oxide varistor (MOV)
          A.1.2 Silicon semiconductors
      A.2 Voltage-switching devices
          A.2.1 Gas discharge tube (GDT)
          A.2.2 Air gaps
          A.2.3 Thyristor surge suppressor (TSS) -
                Fixed voltage types (self-gating)
          A.2.4 Thyristor surge suppressor (TSS) -
                Gated types
Annex B (informative) Current-limiting devices
      B.1 Current-interrupting devices
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          B.1.1 Fusible resistor
          B.1.2 Fuses
          B.1.3 Thermal fuses
      B.2 Current-reducing devices
          B.2.1 Polymer PTC (positive temperature coefficient
                resistor)
          B.2.2 Ceramic PTC
          B.2.3 Electronic current limiters
      B.3 Current-diverting devices
          B.3.1 Heat coils
          B.3.2 Gated thyristor, current operated
          B.3.3 Thermal switch
Annex C (informative) Risk management
      C.1 Risk due to lightning discharges
          C.1.1 Risk assessment
          C.1.2 Risk analysis
          C.1.3 Risk evaluation
          C.1.4 Risk treatment
      C.2 Risk due to power line faults
          C.2.1 AC power systems
to continue
          C.2.2 DC power systems
      C.3 Earth potential rise
Annex D (informative) Transmission characteristics related
                      to IT systems
      D.1 Telecommunications systems
      D.2 Signalling, measurement and control systems
      D.3 Cable TV systems
Annex E (informative) Coordination of SPDs/ITE
      E.1 Determination of UIN and IIN
      E.2 Determine the output protective voltage and current
          waveforms for SPD 1
      E.3 Compare SPD 1 and SPD 2 values
      E.4 Necessity of verification of the
          coordination by testing