1、C.D.U./U.D.C.:621.3.061.001.13 744.423COMMISSION ELECTROTECHNIQUE INTERNATIONALE(afiliee a IOrganisation Internationale de Normalisation-ISO)NORME DE LA CEIINTERNATIONAL ELECTROTECHNICAL COMMISSION(affiliated to the International Organization for Standardization-ISO)IEC STANDARDPublication113-4Premi
2、ere edition-First edition1975Schemas,diagrammes,tableauxQuatrieme partie:Recommandations pour ltablissement des schemas des circuitsDiagrams,charts,tablesPart 4:Recommendations for the preparation of circuit diagramsFOR REFERENCE ONLYSTANDARDS AND SAFETY SFCTIONNATIONAL FNERGY ATHOBITYDroits de repr
3、oduction reserves-Copyright-all rights reservedAucune partie de cette publication ne peut tre reproduite ni utilisee sous No part of this publication may be reproduced or utilized in anyquelque forme que ce soit et par aucun procde,lectronique ou mca-form or by any means,electronic or mechanical,inc
4、luding photocopyingnique,y compris la photocopie et les microfilms,sans Iaccord crit de Iditeur.and microfilm,without permission in writing from the publisher.Bureau Central de la Commission Electrotechnique Internationale1,rue de VarembeGeneve,SuisseIECVOL.10Prix Fr.s.Price S.Fr.70.50-3CONTENTSPage
5、s5FOREWORD5PREFACEClause71.Scope72.Purpose of a circuit diagram.13.Contents of a circuit diagram4.General guiding principles.4.1 Layout.94.2 Functional grouping95.Arrangement of symbols on diagrams.5.1 Methods for indicating symbol location95.2 Methods of circuit representation.5.3 Separation of sym
6、bols in detached representation.115.4 Methods of referencing parts in the case of detached representation155.5 Representation of unused elements175.6 Representation of contacts.216.Representation of circuits6.1 General.6.2 Representation of supply6.3 Representation of main circuits.6.4 Detailed reco
7、mmendations.11136.5 Simplifications.:39D6.6 Recommended layout for some fundamental circuits.7.Markings and designations7.1 Item designation457.2 Designation of terminals and junctions458.Explanatory notes459.Inscription of technical data.10.Examples of complete circuit diagrams50F1 GURES37to48.1-5I
8、NTERNATIONAL ELECTROTECHNICAL COMMISSIONDIAGRAMS,CHARTS,TABLESPart 4:Recommendations for the preparation of circuit diagramsFOREWORD1)The formal decisionis or agreements of the IEC on technical matters,prepared by Technical Committees on which all the NationalCommittees having a special interest the
9、rein are represented,express,as nearly as possible,an international consensus of opinion on2)They have the form of recommendations for international use and they are accepted by the National Committees in that sense.the subjects dealt with.3)In order to promote international unification,the IEC expr
10、esses the wish that all National Committees should adopt the text of theIEC recommendation for their national rules in so far as national conditions will permit.Any divergence between the IEC recom-mendation and the corresponding national rules should,as far as possible,be clearly indicated in the l
11、atter.PREFACEThis recommendation has been prepared by Sub-Committee SC 3B,Preparation of Diagrams,Charts andTables.Item Designation,of IEC Technical Committee No.3,Graphical Symbols.A first draft,prepared by the Secretariat of SC 3B,was discussed at the meeting held in Helsinki in 1971and a second d
12、raft was discussed at the meeting held in Paris in 1972.The draft was submitted to the NationalCommittees for approval under the Six MonthsRule in April 1973.The following countries voted explicitly in favour of publication of Part 4:NetherlandsAustraliaPortugalAustriaRomaniaBelgiumSouth Africa(Repu
13、blic of)DenmarkSwedenFinlandSwitzerlandFranceTurkeyGermanyUnited KingdomItalyUnited States of AmericaJapan9Lines representing conductors on a diagram should be straight with a minimum of cross-overs and changes ofdirection.Individual circuits should preferably be arranged vertically as shown in Figu
14、re 1 or horizontally asshown in Figure 2.In Figures 1 to 36,T-junctions are shown without a dot.In accordance with IEC Publication 117,Recom-mended Graphical Symbols,it is equally permissible to draw T-junctions with a dot or a circle.One of the threemethods should be used consistently in each diagr
15、am or set of diagrams.48674487174FIGURE 1FIGURE 24.2 Functional groupingIt is recommended that symbols for circuit elements performing a basic function,not necessarily in the sameconstructional unit,be grouped together.Whenever possible,functional groups should be arranged so that thesequence of eve
16、nts or signal flow are clear,with other elements also arranged to serve this purpose.Circuits shouldpreferably be drawn so that this sequence is shown from left to right or from top to bottom.5.Arrangement of symbols on diagrams5.1 Methods for indicating symbol location5.1.1 Grid reference systemThe
17、 grid reference system is described in IEC Publication 113-3.For examples,see:Figure 38(pages 51 and 52),using references with sheet numbers and row designations,Figure 39(page 53),using references with column designations,Figures 43(page 60)and 44(page 62),using references with rectangular zone des
18、ignations.5.1.2 Tabular systemAlong a horizontal edge of the drawing,the item designations are repeated above or below the correspondingsymbols.These item designations are usually arranged in rows,a row for capacitors,a row for resistors,etc.See Figure 47(page 65).A similar vertical arrangement is also permissible.5.1.3 Circuit reference systemCircuits such as shown in Figures I and 2 may be identified by circuit numbers.For example,see Figure 40,page 54.
