Electrical installations of buildings - Part 5-53: Selection and erection of electrical equipment - Isolation, switching and control - Section 534: Devices for protection against over
534.1 General
This Part contains provisions for the application of voltage limitation to obtain an insulation coordination in the bases described in IEC 60364-4-44 Low-voltage Electrical Installations - Part 4-44: Protection for Safety - Protection against Voltage Disturbances and Electromagnetic Disturbances, IEC 60664-1 Insulation Coordination for Equipment within Low-voltage Systems - Part 1: Principles, Requirements and Tests, IEC 61312-2 Protection Against Lighting Electromanegetic Impulse (LEMP) - Shielding of Structures, Bonding inside Structures and Earthing and IEC 61643-12 Surge Protective Devices Connected to Low-voltage Power Distribution Systems - Requirements and Tests.
This Part gives the requirements for the selection and erection of surge protective devices (SPDs):
- Surge protective devices (SPDs) for the electrical installations of buildings to obtain a limitation of transient overvoltages of atmospheric origin transmitted via the supply distribution system and against switching overvoltage;
- SPDs for the protection against transient overvoltages caused by direct lighting strikes or lightning strokes in the vicinity of buildings, protected by a lightning protection system.
This Part does not take into account surge protective components which may be incorporated in the appliances connected with electrical installations. The presence of such components may modify the behavior of main surge protective devices of electrical installations and may need additional coordination.
This Part applies to AC power circuit. For DC power circuit, the requirements as described in this Part may be applied as far as is useful. For special applications, other or additional requirements may be necessary in relevant chapters and sections of Part 7 of IEC 60364.
534.2 Selection and Erection of SPDs in Electrical Installations of Buildings
534.2.1 Use of SPDs
Section 443 of IEC 60364-4-44 includes protection against overvoltages of atmospheric origin (caused by indirect, distant lightning strokes) and switching overvoltages. This protection is normally provided by the installation of test class II SPDs and if necessary test class III SPDs.
Foreword I
534.1 General
534.2 Selection and Erection of SPDs in Electrical Installations of Buildings
Appendix A (Informative) Installation of SPDs in TN Systems
Appendix B (Informative) Installation of SPDs in TT Systems
Appendix C (Informative) Installation of SPDs in TT Systems
Appendix D (Informative) Installation of Class I, II and III tested SPDs, for Example in TN-C-S Systems
