1、NEMA Standards PublicationNational Electrical Manufacturers AssociationNEMA IA 2.3-2005Programmable Controllers Part 3: Programming LanguagesNEMA Standards Publication IA 2.3-2005 (Adoption of IEC Publication 61131-3) Programmable Controllers Part 3: Programming Languages Published by: National Elec
2、trical Manufacturers Association 1300 North 17th Street, Suite 1752 Rosslyn, Virginia 22209 www.nema.org Copyright 2005 by the National Electrical Manufacturers Association. All rights including translation into other languages, reserved under the Universal Copyright Convention, the Berne Convention
3、 for the Protection of Literary and Artistic Works, and the International and Pan American Copyright Conventions. NOTICE AND DISCLAIMER The information in this publication was considered technically sound by the consensus of persons engaged in the development and approval of the document at the time
4、 it was developed. Consensus does not necessarily mean that there is unanimous agreement among every person participating in the development of this document. The National Electrical Manufacturers Association (NEMA) standards and guideline publications, of which the document contained herein is one,
5、 are developed through a voluntary consensus standards development process. This process brings together volunteers and/or seeks out the views of persons who have an interest in the topic covered by this publication. While NEMA administers the process and establishes rules to promote fairness in the
6、 development of consensus, it does not write the document and it does not independently test, evaluate, or verify the accuracy or completeness of any information or the soundness of any judgments contained in its standards and guideline publications. NEMA disclaims liability for any personal injury,
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8、ccuracy or completeness of any information published herein, and disclaims and makes no warranty that the information in this document will fulfill any of your particular purposes or needs. NEMA does not undertake to guarantee the performance of any individual manufacturer or sellers products or ser
9、vices by virtue of this standard or guide. In publishing and making this document available, NEMA is not undertaking to render professional or other services for or on behalf of any person or entity, nor is NEMA undertaking to perform any duty owed by any person or entity to someone else. Anyone usi
10、ng this document should rely on his or her own independent judgment or, as appropriate, seek the advice of a competent professional in determining the exercise of reasonable care in any given circumstances. Information and other standards on the topic covered by this publication may be available fro
11、m other sources, which the user may wish to consult for additional views or information not covered by this publication. NEMA has no power, nor does it undertake to police or enforce compliance with the contents of this document. NEMA does not certify, test, or inspect products, designs, or installa
12、tions for safety or health purposes. Any certification or other statement of compliance with any health or safetyrelated information in this document shall not be attributable to NEMA and is solely the responsibility of the certifier or maker of the statement. NEMA IA 2.3-2005 Page i CONTENTS Page F
13、oreword ii Referenced Standards iv Amendments . v IEC 61131-3 1 NEMA IA 2.3-2005 Page ii Foreword This Standards Publication is a NEMA Adoptive Standard based on Part 3 of IEC 61131, Programmable Controllers. This Standards Publication was prepared by a technical committee of the NEMA Automation Pro
14、ducts and Systems Section. It was approved in accordance with the bylaws of NEMA and supersedes NEMA Standards Publication ICS 3-1988, Part 3-304. This Standards Publication provides practical information concerning ratings, construction, test, performance, and manufacture of industrial control equi
15、pment. These standards are used by the electrical industry to provide guidelines for the manufacture and proper application of reliable products and equipment and to promote the benefits of repetitive manufacturing and widespread product availability. NEMA Standards represent the result of many year
16、s of research, investigation, and experience by the members of NEMA, its predecessors, its Sections and Committees. They have been developed through continuing consultation among manufacturers, users, and national engineering societies and have resulted in improved serviceability of electrical produ
17、cts with economies to manufacturers and users. One of the primary purposes of this Standards Publication is to encourage the production of reliable control equipment which, in itself, functions in accordance with these accepted standards. Some portions of these standards, such as electrical spacings
18、 and interrupting ratings, have a direct bearing on safety; almost all of the items in this publication, when applied properly, contribute to safety in one way or another. Properly constructed industrial control equipment is, however, only one factor in minimizing the hazards which may be associated
19、 with the use of electricity. The reduction of hazard involves the joint efforts of the various equipment manufacturers, the system designer, the installer, and the user. Information is provided herein to assist users and others in the proper selection of control equipment. The industrial control ma
20、nufacturer has limited or no control over the following factors which are vital to safe installation: null environmental conditions null system design null equipment selection and application null installation null operating practices null maintenance This publication is not intended to instruct the
21、 user of control equipment with regard to these factors except insofar as suitable equipment to meet needs can be recognized in this publication and some application guidance is given. This Standards Publication is necessarily confined to defining the construction requirements for industrial control
22、 equipment and to providing recommendations for proper selection for use under normal or certain specific conditions. Since any piece of industrial control equipment can be installed, operated, and maintained in such a manner that hazardous conditions may result, conformance with this publication do
23、es not by itself assure a safe installation. When, however, equipment conforming with these standards is properly selected and is installed in accordance with the National Electrical Code and properly maintained, the hazards to persons and property will be reduced. NEMA IA 2.3-2005 Page iii To conti
24、nue to serve the best interests of users, NEMA is actively cooperating with other standardization organizations in the development of simple and more universal metrology practices. In this Standards Publication, the U.S. customary units are gradually being supplemented by those of the modernized met
25、ric system known as the International Systems of Units (SI). This transition involves no changes in standard dimensions, tolerances, or performance specifications. NEMA Standards Publications are subject to periodic review. They are revised frequently to reflect user input and to meet changing condi
26、tions and technical progress. Users should secure the latest editions. Inquiries, comments, and proposed or recommended revisions should be submitted to the concerned NEMA product subdivision by contacting the: Vice President, Technical Services National Electrical Manufacturers Association 1300 Nor
27、th 17th Street Rosslyn, Virginia 22209 NEMA IA 2.3-2005 Page iv Referenced Standards The following standards contain provisions which, through reference in this text, constitute provisions of this NEMA Standards Publication. At the time of publication, the editions indicated were valid. All standard
28、s are subject to revision, and parties to agreements based on this Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. International Electrotechnical Commission 1, rue de Varemb Geneva, Switzerland IEC 61131-3 Programmable Con
29、trollersPart 3: Programming Languages NEMA IA 2.3-2005 Page v Amendments IEC 61131-3, Programmable ControllersPart 3: Programming Languages, is adopted in its entirety. NEMA Adoptive Standard Where a conflict exists between the provisions of IA 2.3 and other NEMA Standards Publications, the provisio
30、ns of IA 2.3 shall govern in the area of programmable controllers and their associated peripherals. NEMA Standard NEMA IA 2.3-2005 Page vi INTERNATIONAL STANDARD IEC61131-3Second edition2003-01Programmable controllers Part 3: Programming languages Automates programmables Partie 3: Langages de progra
31、mmation Reference number IEC 61131-3:2003(E) Publication numbering As from 1 January 1997 all IEC publications are issued with a designation in the 60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1. Consolidated editions The IEC is now publishing consolidated versions of its publ
32、ications. For example, edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the base publication incorporating amendment 1 and the base publication incorporating amendments 1 and 2. Further information on IEC publications The technical content of IEC publications is kept un
33、der constant review by the IEC, thus ensuring that the content reflects current technology. Information relating to this publication, including its validity, is available in the IEC Catalogue of publications (see below) in addition to new editions, amendments and corrigenda. Information on the subje
34、cts under consideration and work in progress undertaken by the technical committee which has prepared this publication, as well as the list of publications issued, is also available from the following: IEC Web Site (www.iec.ch) Catalogue of IEC publications The on-line catalogue on the IEC web site
35、(http:/www.iec.ch/searchpub/cur_fut.htm) enables you to search by a variety of criteria including text searches, technical committees and date of publication. On-line information is also available on recently issued publications, withdrawn and replaced publications, as well as corrigenda. IEC Just P
36、ublished This summary of recently issued publications (http:/www.iec.ch/online_news/ justpub/jp_entry.htm) is also available by email. Please contact the Customer Service Centre (see below) for further information. Customer Service Centre If you have any questions regarding this publication or need
37、further assistance, please contact the Customer Service Centre: Email: custserviec.ch Tel: +41 22 919 02 11 Fax: +41 22 919 03 00 INTERNATIONAL STANDARD IEC61131-3Second edition2003-01Programmable controllers Part 3: Programming languages Automates programmables Partie 3: Langages de programmation I
38、EC 2003 Copyright - all rights reserved No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. International Electrotechnical Commission, 3, rue de Varemb
39、, PO Box 131, CH-1211 Geneva 20, SwitzerlandTelephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmailiec.ch Web: www.iec.ch For price, see current catalogue PRICE CODE Commission Electrotechnique InternationaleInternational Electrotechnical Commission XE 2 61131-3 IEC:2003(E) CONTENTS FOR
40、EWORD 8 1 General9 1.1 Scope.9 1.2 Normative references 9 1.3 Definitions9 1.4 Overview and general requirements .14 1.4.1 Software model.14 1.4.2 Communication model16 1.4.3 Programming model .18 1.5 Compliance19 1.5.1 System compliance 20 1.5.2 Program compliance.22 2 Common elements .23 2.1 Use o
41、f printed characters 23 2.1.1 Character set 23 2.1.2 Identifiers 23 2.1.3 Keywords24 2.1.4 Use of white space 24 2.1.5 Comments 24 2.1.6 Pragmas .25 2.2 External representation of data .25 2.2.1 Numeric literals.25 2.2.2 Character string literals 26 2.2.3 Time literals 28 2.2.3.1 Duration .28 2.2.3.
42、2 Time of day and date.29 2.3 Data types .29 2.3.1 Elementary data types30 2.3.2 Generic data types .31 2.3.3 Derived data types32 2.3.3.1 Declaration 32 2.3.3.2 Initialization33 2.3.3.3 Usage .35 2.4 Variables36 2.4.1 Representation .36 2.4.1.1 Single-element variables .36 2.4.1.2 Multi-element var
43、iables .38 2.4.2 Initialization.38 2.4.3 Declaration .39 2.4.3.1 Type assignment .41 2.4.3.2 Initial value assignment .42 2.5 Program organization units .45 2.5.1 Functions 45 2.5.1.1 Representation 46 2.5.1.2 Execution control.49 2.5.1.3 Declaration 50 2.5.1.4 Typing, overloading, and type conversi
44、on.52 2.5.1.5 Standard functions.55 2.5.1.5.1 Type conversion functions55 2.5.1.5.2 Numerical functions56 2.5.1.5.3 Bit string functions 59 2.5.1.5.4 Selection and comparison functions.59 2.5.1.5.5 Character string functions 62 2.5.1.5.6 Functions of time data types 64 2.5.1.5.7 Functions of enumera
45、ted data types66 61131-3 IEC:2003(E) 3 2.5.2 Function blocks.662.5.2.1 Representation 672.5.2.1a) Use of EN and ENO in function blocks 682.5.2.2 Declaration 692.5.2.3 Standard function blocks.772.5.2.3.1 Bistable elements .772.5.2.3.2 Edge detection782.5.2.3.3 Counters .782.5.2.3.4 Timers.812.5.2.3.
46、5 Communication function blocks832.5.3 Programs832.6 Sequential Function Chart (SFC) elements.842.6.1 General.842.6.2 Steps.842.6.3 Transitions 862.6.4 Actions892.6.4.1 Declaration 892.6.4.2 Association with steps .912.6.4.3 Action blocks .922.6.4.4 Action qualifiers .932.6.4.5 Action control.942.6.
47、5 Rules of evolution.992.6.6 Compatibility of SFC elements.1072.6.7 SFC Compliance requirements 1082.7 Configuration elements1082.7.1 Configurations, resources, and access paths 1102.7.2 Tasks 1143 Textual languages 1233.1 Common elements 1233.2 Instruction list (IL) 1233.2.1 Instructions .1233.2.2
48、Operators, modifiers and operands1243.2.3 Functions and function blocks1263.3 Structured Text (ST)1293.3.1 Expressions 1293.3.2 Statements .1313.3.2.1 Assignment statements .1333.3.2.2 Function and function block control statements 1333.3.2.3 Selection statements .1333.3.2.4 Iteration statements.134
49、4 Graphic languages .1354.1 Common elements 1354.1.1 Representation of lines and blocks .1354.1.2 Direction of flow in networks.1354.1.3 Evaluation of networks .1364.1.4 Execution control elements 1384.2 Ladder diagram (LD) .1394.2.1 Power rails1394.2.2 Link elements and states1394.2.3 Contacts .1404.2.4 Coils1404.2.5 Functions and function blocks1404.2.6 Order of network evaluation .1414.3 Function Block Diagram (FBD)1434.3.1 General.1434.3.2 Combination of elements1434.3.3 Order of network evaluation .14
