C.D.U./U.D.C.: 621.316.31:744.4 5 COMMISSION ELECTROTECHNIQUEINTERNATIONALE (affliee a I'Organisation Internationale de Normalisation -IsO) RECOMMANDATION DE LA CEI INTERNATIONAL ELECTROTECHNICAL COMMISSION (affiliated to the International Organization for Standardization - isO) IECRECOMMENDATION Publication 113-3 Premiere édition - First edition 1974 Schemas, diagrammes, tableaux Troisieme partie: Recommandations generales pour I'etablissement des schemas Diagrams, charts, tables Part 3: General recommendations for the preparation of diagrams Droits de reproduction reserves Copyright -all rights reserved Aucunepartie de cette pubilication ne peut stre reproduiteniutilisee sous No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying quelque forme que ce soit et par aucun procede, electronique ou méca- and microfilm, without permission in writing from the publisher. nique, y compris la photocopie et les microfilms, sans I'accord ecrit de I'editeur. Bureau Central de la Commission Electrotechnique Internationale 1, rue de Varembe Geneve,Suisse IEC Prix Fr. s. VOL.10 32. Price S. Fr. CONTENTS Page FOREWORD 5 PREFACE 5 Clause 1.Introduction 7 2. Drawing sizes 7 3. Application of graphical symbols 7 3.i Different kinds of graphical symbols 7 3.2 Combinations and composition of symbols 9 3.3 Choice of symbols for a diagram 9 3.4 Symbol size, line thicknesses 11 3.5 Orientation of symbols 15 3.6 Representation of terminals 15 3.7 Representation of conductors 15 4. Connecting lines 17 4.1 Identification of connecting lines 17 4.2 Multi-line representation 17 4.3 Single-line representation 17 4.4Omitting lines 19 4.5 Number of conductors 21 5. Application of single-line representation to apparatus 21 6. Methods of indicating symbol location 25 7.Operational state to be represented 27 INTERNATIONAL ELECTROTECHNICAL COMMISSION DIAGRAMS, CHARTS, TABLES Part 3: General recommendations for the preparation of diagrams FOREWORD I) The formal decisions or agreements of the IEC on technical matters, prepared by Technical Committees on which all the National Committees having a special interest therein are represented, express, as nearly as possible, an international consensusofopiniononthe subjectsdealtwith. 2) They have the form of recommendations for international use and they are accepted by the National Committees in that sense 3) In order to promote international unification, the IEC expresses the wish that all National Committees should adopt the text of the IEC recommendation for their national rules in so far as national conditions will permit. Any divergence between the IEC recommendations and the corresponding national rules should, as far as possible, be clearly indicated in the latter. PREFACE This recommendation has been prepared by Sub-Committee 3B, Preparation of Diagrams, Charts and Tables. Item Designation, of IEC Technical Committee No. 3, Graphical Symbols. Two drafts were discussed at the meeting held in Paris in 1972. As a result of this meeting, a combined new draft, document 3B(Central Office)8, was submitted to the National Committees for approval under the Six Months'Rule in February 1973. The following countries voted explicitly in favour of publication of Part 3: Australia Japan Netherlands Austria Belgium Portugal Denmark Romania Egypt South Africa (Republic of) Finland Sweden France Switzerland Germany Turkey Israel United Kingdom Italy United States of America