1、 ANSI/IEEE Std 280-1985(R2003)(Revision of IEEE Std 280-1968and ANSI Y10.5-1968)An American National StandardIEEE Standard Letter Symbols for Quantities Used in Electrical Science and Electrical EngineeringSponsorIEEE Standards Coordinating Committee 14, Graphic Symbols and DesignationsApproved Sept
2、ember 23, 1982Reaffirmed March 20, 2003IEEE Standards BoardApproved May 15, 1984Reaffirmed August 20, 1997American National Standards InstituteAbstract: This standard provides letter symbols to represent various quantities (but not units) used inelectrical science and technology. The standard is com
3、patible with IEC Publication 27, Letter Symbols to beUsed in Electrical Technology. Copyright 1984 byThe Institute of Electrical and Electronics Engineers, Inc345 East 47th Street, New York, NY 10017, USANo part of this publication may be reproduced in any form, in an electronic retrieval system or
4、otherwise, without theprior written permission of the publisher.iiCopyright 1998 IEEE All Rights ReservedDesignation (Variable) HeaderTitleLeft (Variable)ACCEPTANCE NOTICEThe above Non-Government standardization document was adopted 12 December 1984 and is approved for use by theDoD. The indicated i
5、ndustry group has furnished the clearances required by existing regulations. Copies of thedocument are stocked by DoD Single Stock Point, Naval Publications and Forms Center, Philadelphia. PA, 19:120 forissue to DoD activities only. Contractors and industry groups may obtain copies directly from The
6、 Institute ofElectrical and Electronics Engineers, Inc, 345 East 47th Street, New York, NY 10017.Title of Document: IEEE Standard Letter Symbols for Quantities Used in Electrical Science and ElectricalEngineeringDocument No: ANSI/IEEE Std 280-1985 Date of Specic Issue Adopted: 12 December 1984Releas
7、ing Industry Group: The Institute of Electrical and Electronics Engineers, IncorporatedNOTICE: When reafrmation, amendment, revision, or cancellation of this standard is initially proposed, the industrygroup responsible for this standard shall inform the military coordinating activity of the propose
8、d change and requestparticipation.Custodians: Military Coordinating Activity:Army AR Army ARNavy SHAir Force 11User Activities: Project Number DRPR-0254Army ME, MI, ATNavy OS, MC, AS, YDiiiIEEE Standards documents are developed within the Technical Committees of the IEEE Societies and the StandardsC
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12、cted to review at least once every ve years for revision or reafrmation. When a document ismore than ve years old, and has not been reafrmed, it is reasonable to conclude that its contents, although still ofsome value, do not wholly reect the present state of the art. Users are cautioned to check to
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14、te supporting comments.Interpretations: Occasionally questions may arise regarding the meaning of portions of standards as they relate tospecic applications. When the need for interpretations is brought to the attention of IEEE, the Institute will initiateaction to prepare appropriate responses. Sin
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16、ion requestsexcept in those cases where the matter has previously received formal consideration.Comments on standards and requests for interpretations should be addressed to:Secretary, IEEE Standards Board345 East 47th StreetNew York, NY 10017USAAbstractThis standard provides letter symbols to repre
17、sent various quantities (but not like) used in electrical science andtechnology. The standard is compatible with IEC Publication 27, Letter Symbols to be Used in Electrical Technology.ivForeword(This Foreword is not a part of ANSI/IEEE Std 280-1985, IEEE Standard Letter Symbols for Quantities Used i
18、n Electrical Scienceand Electrical Engineering.)This standard was developed from three separate standards, ASA Z10.5-1949, Letter Symbols for ElectricalQuantities, ASA Y10.9-1953, Letter Symbols for Radio, and 57IRE21S1, Letter Symbols and Mathematical Signs.The rst edition of this standard was issu
19、ed as USAS Y10.5-1968 IEEE Std 280-1968, Standard Letter Symbols forQuantities Used in Electrical Science and Electrical Engineering. In the development of this standard the InternationalElectrotechnical Commission Publication 27, Letter Symbols to be Used in Electrical Technology, has been followed
20、closely.In this revision the following changes and additions have been made:1) A new section, Scope, has been added.2) A new section, References has been added.3) Section 3.2 on typography has been expanded and claried.4) Text concerning unit symbols has been expanded and text on the SI system of un
21、its added; these now parallelthe statements in ANSI/IEEE 268-1982 , American National Standard Metric Practice. All units (for example,temperature, pressure, conductance) have been revised to agree with current SI practice.Celsius temperaturereplaces the former terms temperatureand customary tempera
22、tureReciprocal degree Celsiusreplaces reciprocal kelvinReferences to cycle per secondhave been deletedIn Table 6, 6.59, Subscripts, Semiconductor Devices, the terms drain terminal and source terminalwere added.In Table 8 the values of the physical constants have been revised to agree with current in
23、formation.Attention is called to the following related standards:ANSI Y10.20-1975, Mathematical Signs and Symbols for Use in Physical Science and Technology.ANSI/IEEE Std 260-1978, IEEE Standard Letter Symbols for Units of Measurement (SI Units, Customary Inch-Pound Units, and Certain Other Units).A
24、NSI/IEEE Std 268-1982, American National Standard Metric Practice.When this standard was approved the IEEE Standards Coordinating Committee on Quantities and Units,Subcommittee SCC14.3 on Letter Symbols had the following membership:Sidney V. Soanes, Chair Bruce B. Barrow Chester H. Page Conrad R. Mu
25、llerThe IEEE Standards Coordinating Committee on Quantities and Units, SCC14 had the following membership:Bruce B. Barrow, Chair Conrad R. Muller, Secretary Louis E. BarbrowRobert C. Benoit, Jr Andrew F. DunnElwood K. GannettTruman S. GrayHarry HesseWilliam R. KruesiJack M. LoudonChester H. PageDece
26、asedvWhen the IEEE Standards Board approved this standard on September 23, 1982, it had the following membership:Irvin N. Howell, Jr, Chair Edward Chelotti, Vice Chair Sava I. Sherr, Secretary G. Y. R. AllenJ. J. ArchambaultJames H. BeallJohn T. BoettgerJ. V. BonucchiEdward J. CohenLen S. CoreyDonal
27、d C. FleckensteinJay ForsterKurt GreeneJoseph L. KoepfingerIrving KolodnyJohn E. MayDonald T. Michael*A. R. ParsonsJohn P. RiganatiFrank L. RoseRobert W. SeelbachJay A. StewartClifford O. SwansonRobert E. Weiler* Member emeritusviCLAUSE PAGE1. Scope.12. References.13. General Principles of Letter Sy
28、mbol Standardization.13.1 Letter Symbols . 13.2 Alphabets and Typography 23.3 Quantity Symbols. 33.4 Unit Symbols 33.5 The International System of Units (SI) 44. Special Principles for Quantity Symbols in Electrical Science and Electrical Engineering.64.1 Phasor Quantities . 64.2 Conventions . 65. I
29、ntroduction to the Tables .86. Symbols for Quantities9Copyright 1984 IEEE All Rights Reserved1An American National StandardIEEE Standard Letter Symbols for Quantities Used in Electrical Science and Electrical Engineering1. ScopeThis standard covers letter symbols used to represent physical quantitie
30、s in the eld of electrical science and electricalengineering. These symbols are independent of the units (see ANSI/IEEE Std 260-1978 21) employed or specialvalues assigned. Also included are selected symbols for mathematics and for physical constants.2. ReferencesWhen the following American National
31、 Standards referred to in this standard are superseded by a revision approved bythe American National Standards Institute, the latest vision shall be used.1 ANSI Y10.17-1961 (R1973), American National Standard Guide for Selecting Greek Letters Used as LetterSymbols for Engineering Mathematics.2 ANSI
32、/IEEE Std 260-1978, IEEE Standard Letter Symbols for Units of Measurement.3 ANSI/IEEE Std 268-1982, American National Standard Metric Practice.3. General Principles of Letter Symbol Standardization3.1 Letter SymbolsLetter symbols2include symbols for physical quantities (quantity symbols) and symbols
33、 for the units in which thesequantities are measured (unit symbols).A quantity symbol is, in general, a single letter3(for example, Ifor electric current) specied as to general form oftype, and modied when appropriate by one or more subscripts or superscripts. In a given work the same letter symbol1
34、The numbers in brackets correspond to those of the references in Section 22Letter symbolas a technical term does not have the same meaning as either name or abbreviation. An abbreviation is a letter or a combination ofletters (plus sometimes an apostrophe or a full stop) which by convention represen
35、ts a wordor a namein a particular language; hence anabbreviation may be different in a different language. A symbol represents a quantityor a unitand is, therefore, independent of language.EXAMPLE: For electromotive force, the symbol is E, whereas the abbreviation is emf in English, fern in French,
36、and EMK in German. The wordampereis sometimes abbreviated amp; the symbol for this unit is A.3Symbols comprising two letters are sometimes used for numerical transport parameters such as Reynolds number Re.2Copyright 1984 IEEE All Rights ReservedIEEE Std 280-1985 IEEE STANDARD LETTER SYMBOLS FOR QUA
37、NTITIES USEDshould appear throughout for the same physical quantity, regardless of the units employed or of special valuesassigned.A unit symbol4is a letter or group of letters (for example, mm for millimeter), or in a few cases a special sign, that maybe used in place of the name of a unit.3.2 Alph
38、abets and TypographyLetter symbols are mainly restricted to the English and Greek alphabets.5The type families that are used for text inmodern book and journal publishing all include italic (sloping) type faces and related roman (upright) type faces. Theformer are used for quantity symbols, and the
39、latter, for unit symbolsthe distinctions are discussed more fully in thefollowing paragraphs. (In the context of this standard, the term romanis used simply to mean upright in contrast withsloping and carries no connotation regarding serifs, line widths, or the like.) In situations where roman and i
40、talic arenot both available, care shall be taken to avoid confusion between quantities and units. For example, an underline isfrequently used to indicate italic type, and where an underline can be provided, as in manual typewriting, this practiceis often helpful.Unconventional type faces should gene
41、rally not be used for letter symbols. Script and Old English faces, for example,are not appropriate for unit symbols. Such special faces have seen limited use for quantity symbols, but good modernpractice avoids them (see 3.3, last paragraph).Symbols for physical quantities, mathematical variables,
42、indices, and general functions6are printed in italic (sloping)type. For example,A, Aareaecharge of an electronx, y, zCartesian coordinatesi, j, k, nindicesf(x)function of xSymbols for physical units, mathematical constants, specic mathematical functions, operators, and numbers used asindices are pri
43、nted in roman type. For example,cm centimetere base of natural logarithmssin xsine of xJ2(z), Jn(z) Bessel functionsdxdifferential of xSubscripts and superscripts are governed by the above principles. Those that are letter symbols for quantities or forindices are printed in italic type, while all ot
44、hers are printed in roman type, for example,Cpheat capacity at constant pressure paij, a45matrix elementsIi, Ioinput current, output currentxavaverage value of xFor indicating the vector character of a quantity, boldface italic type is used. For example,4Formerly it was common to treat unit symbols
45、in the same manner as general abbreviations, but the current recommendations of the InternationalOrganization for Standardization (ISO), and of many other international and national bodies concerned with standardization, emphasize thesymbolic character of these designations and rigidly prescribe the
46、 manner in which they shall be treated. The concept of the unit symbol is thereforeadopted in this standard.5Greek letters that are easily confused with English letters are avoided. See ANSI Y10.17-1961 (1973), 1.6The term general functionsis used here to contrast with specific mathematical function
47、s, for which roman type is to be used.Copyright 1984 IEEE All Rights Reserved3IN ELECTRICAL SCIENCE AND ELECTRICAL ENGINEERING IEEE Std 280-1985FforceHmagnetic eld strengthOrdinary italic type is used to represent the magnitude of a vector quantity. It is also commonly used for a vectorquantity when
48、 there is no need to draw attention to the vector character of the quantity.When tensor quantities of second or higher order are to be represented by a single letter, sans-serif type should be used(for example, A, B).3.3 Quantity SymbolsQuantity symbols may be used in mathematical expressions in any
49、 way consistent with good mathematical usage. Theproduct of two quantities a, b, is indicated by writing ab. The quotient may be indicated by writing.If more than one solidus (/) is used in any algebraic term, parentheses shall be inserted to remove any ambiguity. Thusone may write (a/b)/c, or a/(b/c), but not a/b/c.Subscripts and superscripts are widely used with quantity symbols. Several subscripts or superscripts, sometimesseparated by commas, may be attached to a single letter. But, so far as logical clarity permits, subscripts andsuper
