IEC_62305-3_Ed._1.0.pdf

FORM FDIS(IEC)/FORMULAIRE FDIS(CEI)2002-08-08 81/264/FDISFINAL DRAFT INTERNATIONAL STANDARDPROJET FINAL DE NORME INTERNATIONALEProject number Numro de projet IEC 62305-3 Ed.1.0 IEC/TC or SC CEI/CE ou SC 81 Secretariat/Secrtariat Italy Submitted for parallel voting in CENELEC Soumis au vote parallle au CENELEC Distributed on/Diffus le 2005-08-19 Voting terminates on/Vote clos le 2005-10-21 Also of interest to the following committees Intresse galement les comits suivants 37A,64,77 Supersedes document Remplace le document 81/240/CDV -81/247A/RVC Functions concerned Fonctions concernes Safety Scurit EMC CEM Environment Environnement Quality assurance Assurance de la qualit INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION LECTROTECHNIQUE INTERNATIONALE THIS DOCUMENT IS A DRAFT DISTRIBUTED FOR APPROVAL.IT MAY NOT BE REFERRED TO AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL,TECHNOLOGICAL,COMMERCIAL AND USER PURPOSES,FINAL DRAFT INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME STANDARDS TO WHICH REFERENCE MAY BE MADE IN NATIONAL REGULATIONS.CE DOCUMENT EST UN PROJET DIFFUS POUR APPROBATION.IL NE PEUT TRE CIT COMME NORME INTERNATIONALE AVANT SA PUBLICATION EN TANT QUE TELLE.OUTRE LE FAIT DTRE EXAMINS POUR TABLIR SILS SONT ACCEPTABLES DES FINS INDUSTRIELLES,TECHNOLOGIQUES ET COMMERCIALES,AINSI QUE DU POINT DE VUE DES UTILISATEURS,LES PROJETS FINAUX DE NORMES INTERNATIONALES DOIVENT PARFOIS TRE EXAMINS EN VUE DE LEUR POSSIBILIT DE DEVENIR DES NORMES POUVANT SERVIR DE RFRENCE DANS LES RGLEMENTATIONS NATIONALES.Title IEC 62305-3 Ed.1.0:Protection against lightning Part 3:Physical damage to structures and life hazard Titre CEI 62305-3 Ed.1.0:Protection contre la foudre Partie 3:Dommages physiques sur les structures et risques humains ATTENTION VOTE PARALLLE CEI CENELEC Lattention des Comits nationaux de la CEI,membres du CENELEC,est attire sur le fait que ce projet final de Norme internationale est soumis au vote parallle.Un bulletin de vote spar pour le vote CENELEC leur sera envoy par le Secrtariat Central du CENELEC.ATTENTION IEC CENELEC PARALLEL VOTING The attention of IEC National Committees,members of CENELEC,is drawn to the fact that this final Draft International Standard(DIS)is submitted for parallel voting.A separate form for CENELEC voting will be sent to them by the CENELEC Central Secretariat.Copyright 2005 International Electrotechnical Commission,IEC.All rights reserved.It is permitted to download this electronic file,to make a copy and to print out the content for the sole purpose of preparing National Committee positions.You may not copy or mirror the file or printed version of the document,or any part of it,for any other purpose without permission in writing from IEC.62305-3/FDIS IEC 2 CONTENTS FOREWORD.6 INTRODUCTION.8 1 Scope.9 2 Normative references.9 3 Terms and definitions.10 4 Lightning protection system(LPS).13 4.1 Class of LPS.13 4.2 Design of the LPS.14 4.3 Continuity of steelwork in reinforced concrete structures.14 5 External lightning protection system.15 5.1 General.15 5.2 Air-termination systems.15 5.3 Down-conductor systems.19 5.4 Earth-termination system.22 5.5 Components.24 5.6 Materials and dimensions.26 6 Internal lightning protection system.29 6.1 General.29 6.2 Lightning equipotential bonding.29 6.3 Electrical insulation of the external LPS.32 7 Maintenance and inspection of an LPS.33 7.1 Application of inspections.33 7.2 Order of inspections.33 7.3 Maintenance.33 8 Protection measures against injury to living beings due to touch and step voltages.34 8.1 Protection measures against touch voltages.34 8.2 Protection measures against step voltages.34 Annex A(normative)Positioning the air-termination system.35 Annex B(normative)Minimum cross-section of the entering cable screen in order to avoid dangerous sparking.41 Annex C(informative)Partitioning of the lightning current amongst down-conductors.42 Annex D(informative)Additional information for LPS in the case of structures with a risk of explosion.46 Annex E(informative)Guidelines for the design,construction,maintenance and inspection of lightning protection systems.52 Bibliography.154 62305-3/FDIS IEC 3 Figure 1 Loop in a down-conductor.20 Figure 2 Minimum length l1 of each earth electrode according to the class of LPS.22 Figure A.1 Volume protected by a vertical air-termination rod.35 Figure A.2 Volume protected by a vertical air-termination rod.36 Figure A.3 Volume protected by a wire air-termination system.36 Figure A.4 Volume protected by isolated wires combined in a mesh according to the protective angle method and rolling sphere method.37 Figure A.5 Volume protected by non-isolated wires combined in a mesh according to the mesh method and the protective angle method.38 Figure A.6 Design of an air-termination system according to the rolling sphere method.39 Figure C.1 Values of coefficient kc in