1、Designation: E 230 03An American National StandardStandard Specification andTemperature-Electromotive Force (EMF) Tables forStandardized Thermocouples1This standard is issued under the fixed designation E 230; the number immediately following the designation indicates the year oforiginal adoption or
2、, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.NoteParagraph 1.1, and Tables 7, 13, 19, 21, and 46 were editorially corrected and the yea
3、r date changed on Sept. 23, 2003.1. Scope1.1 This specification contains reference tables (Tables825) that give temperature-electromotive force (emf) relation-ships for Types B, E, J, K, N, R, S, T, and C thermocouples.2These are the thermocouple types most commonly used inindustry.1.2 Also included
4、 are lists of standard and special toleranceson initial values of emf versus temperature for thermocouples(Table 1), thermocouple extension wires (Table 2), and com-pensating extension wires for thermocouples (Table 3).1.3 Tables 45, included herein, give data on insulationcolor coding for thermocou
5、ple and thermocouple extensionwires as customarily used in the United States.1.4 Recommendations regarding upper temperature limitsfor the thermocouple types referred to in 1.1 are given in Table6.1.5 Tables 2645 give temperature-emf data for single-legthermoelements referenced to platinum (NIST Pt
6、67). Thetables include values for Types BP, BN, JP, JN, KP (same asEP), KN, NP, NN, TP, and TN (same as EN).1.6 Tables for Types RP, RN, SP, and SN thermoelementsare not included since, nominally, Tables 1821 represent thethermoelectric properties of Type RP and SP thermoelementsreferenced to pure p
7、latinum. Tables for the individual thermo-elements of Type C are not included because materials for TypeC thermocouples are normally supplied as matched pairs only.1.7 Polynomial coefficients that may be used for computa-tion of thermocouple emf as a function of temperature aregiven in Table 7. Coef
8、ficients for the emf of each thermocouplepair as well as for the emf of most individual thermoelementsversus platinum are included. Coefficients for type RP and SPthermoelements are not included since they are nominally thesame as for the types R and S thermocouples, and coefficientsfor type RN or S
9、N relative to the nominally similar Pt-67would be insignificant. Coefficients for the individual thermo-elements of type C are not established.1.8 Coefficients for sets of inverse polynomials are given inTable 44. These may be used for computing a close approxi-mation of temperature (C) as a functio
10、n of thermocouple emf.Inverse functions are provided only for thermocouple pairs andare valid only over the emf ranges specified.1.9 This specification is intended to define the thermoelec-tric properties of materials that conform to the relationshipspresented in the tables of this standard and bear
11、 the letterdesignations contained herein. Topics such as ordering infor-mation, physical and mechanical properties, workmanship,testing, and marking are not addressed in this specification. Theuser is referred to specific standards such as SpecificationsE 235, E 574, E 585, E 608, E 1159, or E 1223,
12、 as appropriate,for guidance in these areas.1.10 The temperature-emf data in this specification areintended for industrial and laboratory use.2. Referenced Documents2.1 ASTM Standards:E 235 Specification for Thermocouples, Sheathed, Type K,for Nuclear or for Other High-Reliability Applications3E 574
13、 Specification for Duplex, Base-Metal ThermocoupleWire with Glass Fiber or Silica Fiber Insulation3E 585 Specification for Sheathed Base-Metal Thermo-couple Materials3E 608 Specification for Metal-Sheathed Base-Metal Ther-mocouples3E 1159 Specification for Thermocouple Materials,Platinum-Rhodium All
14、oys, and Platinum3E 1223 Specification for Type N Thermocouple Wire32.2 NIST Monograph:NIST Monograph 175 Temperature-Electromotive ForceReference Functions and Tables for the Letter-DesignatedThermocouple Types Based on the ITS-9041These tables are under the jurisdiction of ASTM Committee E20 on Te
15、mpera-ture Measurement and are the direct responsibility of Subcommittee E20.04 onThermocouples.Current edition approved September 23, 2003. Published September 2003.Originally approved in 1963 . Last previous edition approved in 2002 as E 230 02.2These temperature-emf relationships have been revise
16、d as required by theinternational adoption in 1989 of a revised International Temperature Scale(ITS-90).3Annual Book of ASTM Standards, Vol 14.03.4Available from National Institute of Standards and Technology, U.S. Depart-ment of Commerce, Gaithersburg, MD 20899.1Copyright ASTM International, 100 Ba
17、rr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.2.3 IEC Standard:IEC 5843 First edition, 19893. Source of Data3.1 The data in these tables are based upon the SI volt5andthe International Temperature Scale of 1990.3.2 The temperature-emf data in Tables 823 and 2645,toget
18、her with the corresponding equations in Tables 7 and 46for all of the thermocouple types, except type C, have beenextracted from NIST Monograph 175. Temperature-emf data inTables 2425 and the coefficients for type C in Tables 7 and 46have been developed from curves fitted to wire manufacturersdata.N
19、OTE 1It is beyond the scope of this standard to discuss the origin ofthese tables, but if further information is desired, the reader should consultthe NIST reference noted above.3.3 These tables give emf values to three decimalplaces (1 V) at temperature intervals of one degree. Suchtables are satis
20、factory for most industrial uses but may not beadequate for computer and similar applications. If greaterprecision is required, the reader should refer to the NISTreference noted above which includes tables giving emf valuesto four decimal places (0.1 V) for each type except type C.Equations which p
21、ermit easy and unique generation of thetemperature-emf relationships will be found in Table 7. Forconvenience, coefficients of inverse polynomials that may beused to compute approximate temperature (C) as a function ofthermocouple emf are given in Table 46.4. Thermocouple Types and Letter Designatio
22、ns4.1 The letter symbols identifying each reference table arethose which are in common use throughout industry andidentify the following thermocouple calibrations:4.1.1 Type BPlatinum-30% rhodium (+) versus platinum-6 % rhodium ().4.1.2 Type ENickel-10 % chromium (+) versus copper-45% nickel (consta
23、ntan) ().4.1.3 Type JIron (+) versus copper-45% nickel (constan-tan) ().4.1.4 Type KNickel-10 % chromium (+) versus nickel-5 % (aluminum, silicon) () (Note 2).NOTE 2Silicon, or aluminum and silicon, may be present in combi-nation with other elements.4.1.5 Type NNickel-14 % chromium, 112 % silicon (
24、+ )versus nickel-412 % silicon-110 % magnesium ().4.1.6 Type RPlatinum-13 % rhodium ( + ) versus plati-num ().4.1.7 Type SPlatinum-10 % rhodium ( + ) versus platinum().4.1.8 Type TCopper ( + ) versus copper-45% nickel (con-stantan) ().4.1.9 Type CTungsten-5% Rhenium (+) versus Tungsten-26% Rhenium (
25、).4.2 Each letter designation of 4.1 identifies a specifictemperature-emf relationship (Tables 823) and may be ap-plied to any thermocouple conforming thereto within statedtolerances on initial values of emf versus temperature, regard-less of its composition.4.3 The thermoelement identifying symbols
26、 in Tables 26 to45 use the suffix letters P and N to denote, respectively, thepositive and negative thermoelement of a given thermocoupletype.4.4 Tables 26 to 45 identify specific temperature-emf rela-tionships of individual thermoelements with respect to plati-num (NIST Pt-67). Although tolerances
27、on initial values of emfversus temperature, in most cases, are not established forindividual thermoelements with respect to platinum, the appro-priate letter designation may be applied to any thermoelementwhich, when combined with its mating thermoelement, willform a thermocouple conforming to the c
28、orresponding tablewithin the stated tolerances.4.5 An overall suffix letter “X” (for example KX, TX, EPX,JNX) denotes an “extension grade” material whose thermo-electric properties will match those of the correspondingthermocouple type within the stated extension grade tolerancesover a limited tempe
29、rature span. Most base metal extensionwires have the same nominal composition as the thermocouplewires with which they are intended to be used, whereas thecompensating extension wires for noble metal or refractorymetal thermocouple types (S, R, B, or C) are usually of adifferent, more economical com
30、position whose relative ther-moelectric properties as a pair nonetheless closely approximatethose of the noble metal or refractory metal thermocoupleswith which they are to be used.5. Tolerances on Initial Values of EMF versusTemperature5.1 Thermocouples and matched thermocouple wire pairsare normal
31、ly supplied to the tolerances on initial values of emfversus temperature listed in Table 1.5.1.1 Tolerances on initial values of emf versus temperaturefor single-leg thermoelements referenced to platinum havebeen established only for Types KP and KN. These aresupplied, by common practice, to a toler
32、ance equivalent to onehalf the millivolt tolerance of the Type K thermocouple.5.1.2 For all other thermocouple types, tolerances on initialvalues of emf versus temperature for single thermoelements,when required, should be established by agreement betweenthe consumer and the producer.5.1.3 In refere
33、nce Tables 34, 35, 44, and 45, the thermoele-ments are identified by two thermoelement symbols indicatingtheir applicability to two thermocouple types. This indicatesthat the temperature-electromotive force relationship of thetable is typical of the referenced thermoelements over thetemperature rang
34、e given in Table 1 for the correspondingthermocouple type. It should not be assumed, however, thatthermoelements used with one thermocouple type are inter-changeable with those of the other, or that they have the samemillivolt tolerances for the initial values of emf versus tem-perature.5Discussed i
35、n NIST Technical Note 1263, Guidelines for Implementing the NewRepresentations of the Volt and Ohm Effective January 1, 1990.E2300325.2 Thermocouple extension wires and compensating exten-sion wires are supplied to the tolerances on initial values of emfversus temperature shown in Tables 23.5.2.1 Th
36、e initial tolerances of extension grade materials andcompensating extension materials apply over a more limitedspan of temperature than the corresponding thermocouplegrade materials. Applicable temperature ranges, consistent withtypical usage, are given in Tables 23.6. Color Coding6.1 Color codes fo
37、r insulation on thermocouple grade ma-terials, along with corresponding thermocouple and thermoele-ment letter designations, are given in Table 4.6.2 Extension wires for thermocouples are distinguished byhaving an identifying color in the outer jacket as shown inTable 5, where letter designations fo
38、r the extension thermoele-ments and pairs are also presented.6.3 Information in Tables 45 is based on customary UnitedStates practice.NOTE 3Other insulation color coding conventions may be found inuse elsewhere in the world.7. List of Tables7.1 Following is a list of the tables included in this stan
39、dard:7.1.1 General Tables:TableNumber Title1 Tolerances on Initial Values of Emf versus Temperature forThermocouples2 Tolerances on Initial Values of Emf versus Temperature for Ex-tension Wires3 Tolerances on Initial Values of Emf versus Temperature forCompensating Extension Wires4 United States Col
40、or Codes for Single and Duplex InsulatedThermocouple Wires5 United States Color Codes for Single and Duplex InsulatedExtension Wires6 Suggested Upper Temperature Limits for Protected Thermo-couples7 Polynomial Coefficients for Generating Thermocouple EMF asa Function of Temperature7.1.2 EMF versus T
41、emperature Tables for Thermocouples:TableNumberThermocoupleTypeTemperatureRangeA8 B 0 to 1820C9 B 32 to 3308F10 E 270 to 1000C11 E 454 to 1832F12 J 210 to 1200CTableNumberThermocoupleTypeTemperatureRangeA13 J 346 to 2192F14 K 270 to 1372C15 K 454 to 2500F16 N 270 to 1300C17 N 454 to 2372F18 R 50 to
42、1768C19 R 58 to 3214F20 S 50 to 1768C21 S 58 to 3214F22 T 270 to 400C23 T 454 to 752F24 C 0 to 2315C25 C 32 to 4200F7.1.3 EMF versus Temperature Tables for Thermoelements:Table Number Thermocouple TypeThermoele-ment TypeTemperatureRangeA26 B BP 0 to 1768C27 B BP 32 to 3214F28 B BN 0 to 1768C29 B BN
43、32 to 3214F30 J JP 210 to 760C31 J JP 346 to 1400F32 J JN 210 to 760C33 J JN 346 to 1400F34 K or E KP or EP 270 to 1372C35 K or E KP or EP 454 to 2500F36 K KN 270 to 1372C37 K KN 454 to 2500F38 N NP 200 to 1300C39 N NP 328 to 2372F40 N NN 200 to 1300C41 N NN 328 to 2372F42 T TP 270 to 400C43 T TP 45
44、4 to 752F44 T or E TN or EN 270 to 1000C45 T or E TN or EN 454 to 1832FAThese temperature ranges represent the range of published temperatureversus emf data for the thermocouple and thermoelement types listed. Refer toTable 6 for recommended maximum upper use temperature limits for a specificthermoc
45、ouple wire size and type.7.1.4 Supplementary Table:TableNumberTitle46 Coefficients of Inverse Polynomials for Computationof Approximate Temperature as a Function of Ther-mocouple EMF8. Keywords8.1 emf computation; compensating extension wire; inversepolynomial; polynomial coefficient; reference tabl
46、es; thermo-couple; thermocouple extension wire; thermoelement; uppertemperature limitE230033APPENDIX(Nonmandatory Information)X1. IEC COLOR CODE SYSTEMX1.1 GeneralX1.1.1 The data presented in Tables 45 of this specificationshow the color coding required by this specification. Thosecolors are well es
47、tablished in the United States and have beenin use as the national standard there for many years.X1.1.2 In other parts of the world, there are alternative colorcode systems, either now in use, or in process of beingimplemented.X1.1.3 One such color code system is that established by theIEC. The IEC
48、color code system is outlined here for reference.Table X1.1 shows the IEC standard colors for thermocouplecables, extension cables, and compensating cables.TABLE 1 Tolerances on Initial Values of Emf vs. Temperature for ThermocouplesNOTE 1Tolerances in this table apply to new essentially homogeneous
49、 thermocouple wire, normally in the size range 0.25 to 3 mm in diameter(No. 30 to No. 8 Awg) and used at temperatures not exceeding the recommended limits of Table 6. If used at higher temperatures these tolerances maynot apply.NOTE 2At a given temperature that is expressed in C, the tolerance expressed in F is 1.8 times larger than the tolerance expressed in C. Note thatwherever applicable, percentage-based tolerances must be computed from temperatures that are expressed
