C.D.U./U.D.C.: 003.62:681.325.6.004.14 744.423:681.3.056 24 COMMISSIONEI.ECTROTECHNIQUEINTERNATIONALE NORME DELACEI INTERNATIONALELECTROTECHNICALCOMMISSION IECSTANDARD Publication 113-7 Premiere edition --- First edition 1981 Schernas, diagrammes, tableaux Septieme partie: Etablissement des logigrammes Diagrams, charts, tables Part 7: Preparation of logic diagrams Mots cles: symboles d'operateurs logiques: Keywords:symbolsforlogicelements; etablissementdes schemas. preparation of diagrams. Droits de reproduction reserves --- Copyright - all rights reserved No partofthis pubication may be reproduced orutilized inanyform orby Aucune partie de cette publication ne peut etre reproduite ni utilisee sous quelque fomquecesitraunproed,etroueumanuempri any means, electronicor mechanical, including photocopying and microfm photocopie et les microfilms, sans I'accord ecrit tle I'éditeur. without permission in writing from the publisher. Bureau Central de la Commission Electrotechnique Internationale 1, rue de Varembe IEC Geneve, Suisse VoL.I0 CONTENTS Page FOREWORD 5 PREFACE 5 Clause 1. Scope 7 2. Related publications 7 3. Symbols . 4. Logic conventions 11 5.Contentsofalogicdiagram 11 6. Layout of a diagram 11 7. Unused elements 13 8. Distributed connections 13 9. Complex logic units 13 10. Symbols for logic elements 13 11. Labelling of lines 13 12. Use of waveforms 25 13. Tabular information 25. 14. Representation of a pin connection acting at different times as either an input or an output . 25 15.Interactionoflogicelements andotherdevices 25 26 16.Examplesoflogicdiag,rams ApPENDIxACommonlyused.mnemonics 30 ApPENDIx B -- Guide to the meaning, interpretation and selection of logic symbols 35 INTERNATIONALELECTROTECHNICALCOMMISSION DIAGRAMS, CHARTS, TABLES Part 7: Preparation of logic diagrams FOREWORD I) The formal decisions or agreemients 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 consensus of opinionon the sutbjects dealt with. 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 the latter. PREFACE This standard has been prepared by Sub-Committee 3B: Preparation of Diagrams, Charts and Tables. Item Designation, of IEC Technical Committee No. 3: Graphical Symbols. Drafts were discussed at the meetings held in Milan in 1975 and in Oslo in 1976. As a result of this latter meeting, a draft, December1976. The National Committees of the following countries voted explicitly in favour of publication: Australia France Spain Austria Israel Sweden Belgium Japan Switzerland Canada Korea (Republic of) Turkey Denmark Netherlands United Kingdom Egypt SouthAfrica (Republic of) Yugoslavia Finland The document was not published at that time, however, as, during the preparatory work, it was realized that additional material would be needed. A first draft for this supplement, comprising Clauses 11, 14, 15 and Appendices A and B, was discussed at the meeting held in Paris in 1978. As a result of this meeting, a combined draft, Document 3B(Central Office)22, which included the contents of Document 3B(Central Office)19 and the text of the draft supplement, was submitted to the National Committees for approval under the Six Months' Rule in May 1979. TheNational Committeesofthefollowingcountriesvotedexplicitlyinfavourofpublicationof thedraft supplement： Australia Germany Sweden Austria Israel Switzerland Belgium Italy Turkey Canada Japan Unionof Soviet Egypt Norway Socialist Republics Finland South Africa (Republic of) UnitedKingdom Other IEC publications quoted in this standard: Publications N