1、C.D.U./U.D.C.:003.62:681.325.6.004.14 744.423:681.3.05629COMMISSION ELECTROTECHNIQUE INTERNATIONALENORME DE LA CEIINTERNATIONAL ELECTROTECHNICAL COMMISSIONIEC STANDARDPublication 113-7Premiere edition-First edition1981Schemas,diagrammes,tableauxSeptieme partie:Etablissement des logigrammesDiagrams,c
2、harts,tablesPart 7:Preparation of logic diagramsMots cles:symboles doperateurs logiques;Key words:symbols for logic elements;etablissement des schemas.preparation of diagrams.Droits de reproduction reserves-Copyright-all rights reservedAucune partie de cette publication ne peut tre reproduite ni uti
3、lise sous quelque No part of this publication may be reproduced or utilized in any form or byforme que ce soit et par aucun procede,lectronique ou mcanique,y compris la any means,electronic or mechanical,including photocopying and microfilm,photocopie et les microfilms,sans laccord ecrit le Iediteur
4、.without permission in writing from the publisher.Bureau Central de la Commission Electrotechnique Internationale1,rue de VarembeIECGeneve,SuisseVOL.10irs.65.一-3-CONTENTSPageFOREWORD.5PREFACE.Clause71.Scope.72.Related publications.3.Symbols.4.Logic conventions.115.Contents of a logic diagram.116.Lay
5、out of a diagram.117.Unused elements.138.Distributed connections.139.Complex logic units.1310.Symbols for logic elements.1311.Labelling of lines.1312.Use of waveforms.2513.Tabular information.2514.Representation of a pin connection acting at different times as either an input or an output.2515.Inter
6、action of logic elements and other devices.2516.Examples of logic diagrams.26APPENDIX A-Commonly used mnemonics.30APPENDIX B-Guide to the meaning,interpretation and selection of logic symbols.355-INTERNATIONAL ELECTROTECHNICAL COMMISSIONDIAGRAMS,CHARTS,TABLESPart 7:Preparation of logic diagramsFOREW
7、ORD1)The formal decisions or agreements of the IEC on technical matters,prepared by Technical Committees on which all theNational Committees having a special interest therein are represented,express,as nearly as possible,an internationalconsensus of opinion on the subjects dealt with.2)They have the
8、 form of recommendations for international use and they are accepted by the National Committees in thatsense.3)In order to promote international unification,the IEC expresses the wish that all National Commitees should adopt thetext of the IEC recommendation for their national rules in so far as nat
9、ional conditions will permit.Any divergencebetween the IEC recommendation and the corresponding national rules should,as far as possible,be clearly indicated inthe latter.PREFACEThis standard has been prepared by Sub-Committee 3B:Preparation of Diagrams,Charts and Tables.Item Designation,ofIEC Techn
10、ical 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,Document 3B(Central Office)19,was submitted to the National Committees for approval under the Six Months Rule inDecember 1976.The National
11、Committees of the following countries voted explicitly in favour of publication:AustraliaFranceSpainAustriaIsraelSwedenJapanSwitzerlandBelgiumCanadaKorea(Republic of)TurkeyUnited KingdomDenmarkNetherlandsSouth Africa(Republic of)YugoslaviaEgyptFinlandThe document was not published at that time,howev
12、er,as,during the preparatory work,it was realized that additionalmaterial would be needed.A first draft for this supplement,comprising Clauses 11,14,15 and Appendices A and B,wasdiscussed at the meeting held in Paris in 1978.As a result of this meeting,a combined draft,Document 3B(Central Office)22,
13、which included the contents of Document 3B(Central Office)19 and the text of the draft supplement,was submitted to theNational Committees for approval under the Six Months Rule in May 1979.The National Committees of the following countries voted explicitly in favour of publication of the draft suppl
14、ement:SwedenAustraliaGermanyIsraelSwitzerlandAustriaItalyTurkeyBelgiumJapanUnion of SovietCanadaNorwaySocialist RepublicsEgyptUnited KingdomFinlandSouth Africa(Republic of)Other IEC publications quoted in this standard:Publications Nos.113-3:Diagrams,Charts,Tables,Part 3:General Recommendations for
15、the Preparation ofDiagrams.113-4:Part 4:Recommendations for the Preparation of Circuit Diagrams.117-15:Recommended Graphical Symbols,Part 15:Binary Logic Elements.617-12:Graphical Symbols for Diagrams,Part 12:Binary Logic Elements(in preparation).Until thisstandard is published reference should be m
16、ade to Publication 117-15,quoted above.7DIAGRAMS,CHARTS,TABLESPart 7:Preparation of logic diagrams1.ScopeThis standard gives additional recommendations for the preparation of diagrams with respectto the use of symbols for logic elements.2.Related publicationsThe other parts of IEC Publication 113*ar
17、e concerned with matters of drawing practice andprovide additional guidance.Graphical symbols for diagrams are given in the relevant parts of IEC Publication 117:Recommended Graphical Symbols,and IEC Publication 617:Graphical Symbols forDiagrams*.3.Symbols3.1 GeneralSymbols for binary logic elements
18、 and some rules for the use of the symbols are given inIEC Publication 617-12.In accordance with Sub-clause 3.4 of IEC Publication 113-3,their size should be governedby the space necessary for internal annotations and the length of the side needed to accom-modate input and output lines at an accepta
19、ble spacing.Input and output lines are preferably placed on opposite sides of the symbol and should jointhe outline of the symbol at right angles.A symbol for a binary logic element may have anynumber of inputs and outputs provided that the symbol definition requirements as contained inIEC Publicati
20、on 617-12 are met.The special rules for complex elements must be observed.Most logic diagrams will also require the use of symbols drawn from some of the other partsof IEC Publications 117 and 617.3.2 Combination of symbolsRules for combining symbols for basic operations are given in IEC Publication
21、 617-12.Symbols representing hardware elements which are contained in one physical package may alsobe combined providing the interconnections are not accessible to the user and the rulesmentioned above are applied.See inside back cover93.3 Symbol orientationThe symbols contained in IEC Publication 6
22、17-12 have been designed so that inputs appearon the left and outputs on the right,and this orientation is preferred.However,the other symbolorientation in which inputs appear at the top and outputs at the bottom may also be used,provided the following rules are observed:a)In general,outputs appear
23、on the opposite side of the symbols from the inputs.b)The rules for the placement of the qualifying symbol(s)for the device function given in I ECPublication 617-12 are obeyed.c)Sufficient space is provided to avoid confusion between the qualifying symbol(s)for thefunction and the input and output l
24、abels.d)Strings of characters,forming qualifying symbols or labels,should preferably appear innormal reading order.Each input(output)label is centred with respect to its input(output)line.e)The orientation of qualifying symbols for negation,polarity,grouping dynamic input,inhibit and amplification with respect to the connection lines is unchanged.Table I gives examples of symbol orientation.TABLE IPreferred orientationOther permitted orientationD11J$&1JsL&ClL&R1J1K&1K7RC2+CIV RLiD2D2D2D2DC1C22D2D C11C1C1C1C172D C12D C11
