1、Designation: E230/E230M 111An American National StandardStandard Specification andTemperature-Electromotive Force (emf) Tables forStandardized Thermocouples1This standard is issued under the fixed designation E230/E230M; the number immediately following the designation indicates the yearof original
2、adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTETable 46 was changed editorially in October 2011.1. Scope1.1 This specifica
3、tion contains reference tables (Tables 8 to25) 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. The tables contain all of the temperature-emf datacurrently available f
4、or the thermocouple types covered by thisstandard and may include data outside of the recommendedupper temperature limit of an included thermocouple type.1.2 In addition, the specification includes standard andspecial tolerances on initial values of emf versus temperaturefor thermocouples (Table 1),
5、 thermocouple extension wires(Table 2), and compensating extension wires for thermo-couples (Table 3). Users should note that the stated tolerancesapply only to the temperature ranges specified for the thermo-couple types as given in Tables 1, 2, and 3, and do not apply tothe temperature ranges cove
6、red in Tables 8 to 25.1.3 Tables 4 and 5 provide insulation color coding forthermocouple and thermocouple extension wires as customar-ily used in the United States.1.4 Recommendations regarding upper temperature limitsfor the thermocouple types referred to in 1.1 are provided inTable 6.1.5 Tables 26
7、 to 45 give temperature-emf data for single-legthermoelements referenced to platinum (NIST Pt-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 18
8、 to 21 represent thethermoelectric properties of Type RP and SP thermoelementsreferenced to pure platinum. 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 which may
9、be used for compu-tation of thermocouple emf as a function of temperature aregiven in Table 7. Coefficients 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
10、they are nominally thesame as for types R and S thermocouples, and coefficients fortype RN or SN relative to the nominally similar Pt-67 would beinsignificant. Coefficients for the individual thermoelements ofType C thermocouples have not been established.1.8 Coefficients for sets of inverse polynom
11、ials are given inTable 46. These may be used for computing a close approxi-mation of temperature (C) as a function 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 thermoele
12、c-tric properties of materials that conform to the relationshipspresented in the tables of this standard and bear the letterdesignations contained herein. Topics such as ordering infor-mation, physical and mechanical properties, workmanship,testing, and marking are not addressed in this specificatio
13、n.Theuser is referred to specific standards such as SpecificationsE235, E574, E585/E585M, E608/E608M, E1159,orE2181/E2181M for guidance in these areas.1.10 The temperature-emf data in this specification areintended for industrial and laboratory use.1.11 Thermocouple color codes per IEC 5843 are give
14、n inAppendix X1.1.12 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, each1These tables are under the jurisdiction of ASTM Committee E20 on Tempera-ture Measurement and are the
15、direct responsibility of Subcommittee E20.04 onThermocouples.Current edition approved May 15, 2011. Published October 2011. Originallyapproved in 1963. Last previous edition approved in 2003 as E230 03. DOI:10.1520/E0230_E0230M-11E01.2These temperature-emf relationships have been revised as required
16、 by theinternational adoption in 1989 of a revised International Temperature Scale(ITS-90).1Copyright. ASTM International, 100 Barr Harbour Dr., P.O. box C700 West Conshohocken, Pennsylvania 19428-2959, United StatesCopyright by ASTM Intl (all rights reserved); Wed Nov 2 21:56:38 EDT 2011Downloaded/
17、printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions authorized.system shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.13 This standard does not purport to address all of thesafety concerns,
18、 if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3E235 Specification for Thermocouples, Sheath
19、ed, Type Kand Type N, for Nuclear or for Other High-ReliabilityApplicationsE574 Specification for Duplex, Base Metal ThermocoupleWire With Glass Fiber or Silica Fiber InsulationE585/E585M Specification for Compacted Mineral-Insulated, Metal-Sheathed, Base Metal ThermocoupleCableE608/E608M Specificat
20、ion for Mineral-Insulated, Metal-Sheathed Base Metal ThermocouplesE1159 Specification for Thermocouple Materials, Platinum-Rhodium Alloys, and PlatinumE2181/E2181M Specification for Compacted Mineral-Insulated, Metal-Sheathed, Noble Metal Thermocouplesand Thermocouple Cable2.2 NIST Monograph:NIST Mo
21、nograph 175 Temperature-Electromotive ForceReference Functions and Tables for the Letter-DesignatedThermocouple Types Based on the ITS-9042.3 IEC Standard:IEC 5843 Thermocouples Part 3: Extension and Com-pensating Cables Tolerances and Identification System,19893. Source of Data3.1 The data in these
22、 tables are based upon the SI volt5andthe International Temperature Scale of 1990 (ITS-90).3.2 The temperature-emf data in Tables 8 to 23 and 26 to 45,together with the corresponding equations in Tables 7 and 46for all thermocouple types except Type C, have been extractedfrom NIST Monograph 175. Tem
23、perature-emf data inTables 24 and 25 and the coefficients for Type C in Tables 7and 46 have been developed from curves fitted to wiremanufacturers data.NOTE 1It is beyond the scope of this standard to discuss the origin ofthese tables. If further information is required, the reader should consultNIS
24、T Monograph 175.3.3 These tables give emf values to three decimalplaces (1 V) at temperature intervals of one degree. The tablesare satisfactory for most industrial uses but may not beadequate for computer and similar applications. If greaterprecision is required, the reader should refer to NIST Mon
25、o-graph 175 which includes tables giving emf values to fourdecimal places (0.1 V) for each type except Type C. Equa-tions which permit easy and unique generation of thetemperature-emf relationships can be found in Table 7. Forconvenience, coefficients of inverse polynomials that may beused to calcul
26、ate approximate temperature (C) as a function ofthermocouple emf are given in Table 46.4. Thermocouple Types and Letter Designations4.1 The letter symbols identifying each reference table arethose which are in common use throughout industry andidentify the following thermocouple calibrations:4.1.1 T
27、ype BPlatinum-30 % rhodium (+) versus platinum-6 % rhodium ().4.1.2 Type ENickel-10 % chromium (+) versus copper-45 % nickel (constantan) ().4.1.3 Type JIron (+) versus copper-45 % nickel (constan-tan) ().4.1.4 Type KNickel-10 % chromium (+) versus nickel-5 % (aluminum, silicon) ().NOTE 2Silicon, or
28、 aluminum and silicon, may be present in combi-nation with other elements.4.1.5 Type NNickel-14 % chromium, 1.5 % silicon (+)versus nickel-4.5 % silicon-0.1 % magnesium ().4.1.6 Type RPlatinum-13 % rhodium (+) versus platinum().4.1.7 Type SPlatinum-10 % rhodium (+) versus platinum().4.1.8 Type TCopp
29、er (+) versus copper-45 % nickel (con-stantan) ().4.1.9 Type CTungsten-5 % Rhenium (+) versus Tungsten-26 % Rhenium ().4.2 Each letter designation in 4.1 identifies a specifictemperature-emf relationship (Tables 8 to 25) and may beapplied to any thermocouple conforming thereto within statedtolerance
30、s on initial values of emf versus temperature, regard-less of its composition.4.3 The thermoelement identifying symbols 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 t
31、emperature-emf rela-tionships of individual thermoelements with respect to plati-num (NIST Pt-67). The appropriate letter designation may beapplied to any thermoelement which, when combined with itsmating thermoelement, will form a thermocouple conformingto the corresponding table within the stated
32、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 temperature range. Most base metal extens
33、ionwires have the same nominal composition as the thermocouplewires with which they are intended to be used, whereas thecompensating extension wires for noble metal or refractory3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org.
34、For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Available from National Institute of Standards and Technology (NIST), 100Bureau Dr., Stop 1070, Gaithersburg, MD 20899.5Discussed in NISTTechnical Note 1263, Guidelines for Implement
35、ing the NewRepresentations of the Volt and Ohm Effective January 1, 1990.E230/E230M 1112Copyright by ASTM Intl (all rights reserved); Wed Nov 2 21:56:38 EDT 2011Downloaded/printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions authorized.metal thermocouple types (S, R, B,
36、 or C) are usually of adifferent, more economical composition 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 over a limited temperaturerange.5. Tolerances on Initial Values of
37、 Emf versusTemperature5.1 In the United States, thermocouples and matched ther-mocouple wire pairs are normally supplied conforming to thetolerances on initial values of emf versus temperature providedin Table 1.5.1.1 Tolerances on initial values of emf versus temperaturefor single-leg thermoelement
38、s referenced to platinum havebeen established only for Types KP and KN. These aresupplied, by common practice, to a tolerance 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 sin
39、gle thermoelementsshould be established by agreement between the purchaser andthe supplier.5.1.3 In Tables 34, 35, 44, and 45, the thermoelements areidentified by two thermoelement symbols indicating theirapplicability to two thermocouple types. This indicates that thetemperature-electromotive force
40、 relationship of the table istypical of the referenced thermoelements over the temperaturerange given in Table 1 for the corresponding thermocoupletype. It should not be assumed, however, that thermoelementsused with one thermocouple type are interchangeable withthose of the other, or that they have
41、 the same millivolttolerances for the initial values of emf versus temperature.5.2 Thermocouple extension wires and compensating exten-sion wires are supplied to conform to the tolerances on initialvalues of emf versus temperature shown in Tables 2 and 3,respectively.5.2.1 Initial tolerances of exte
42、nsion grade materials andcompensating extension materials apply over a more limitedrange of temperature than the corresponding thermocouplegrade materials.Applicable temperature ranges, consistent withtypical usage, are given in Tables 2 and 3.6. Color Coding6.1 Color codes for insulation on thermoc
43、ouple 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 for the extension thermoe
44、le-ments and pairs are also presented.6.3 Information presented in Tables 4 and 5 is based oncustomary practice in the United States.NOTE 3Other insulation color coding conventions may be found inuse elsewhere in the world. Refer to Appendix X1 for information.7. List of Tables7.1 Following is a lis
45、t of the tables included in this standard: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 forCompensati
46、ng Extension Wires4 United States Color Codes for Single and Duplex InsulatedThermocouple Wire5 United States Color Codes for Single and Duplex InsulatedExtension Wire6 Suggested Upper Temperature Limits for Protected Thermo-couples7 Polynomial Coefficients for Generating Thermocouple Emf as aFuncti
47、on of Temperature7.1.2 Emf versus Temperature Tables for Thermocouples:TableNumberThermocoupleTypeTemperatureRangeA8 B 0 to 1820C9 B 32 to 3308F10 E 270 to 1000C11 E 454 to 1832F12 J 210 to 1200C13 J 346 to 2192F14 K 270 to 1372C15 K 454 to 2500F16 N 270 to 1300C17 N 454 to 2372F18 R 50 to 1768C19 R
48、 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 32 to 321
49、4F30 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 454 to 752F44 T or E TN or EN 270 to 1000C45 T or E TN or EN 454 to 1832FAThese temperature ranges represent the published temperature versus emfdata for the thermocouple and thermoelement types l
