1、Designation: E230/E230M 111 E230/E230M 12 An 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 y
2、earof original 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.1 NOTETable 46 was changed editorially in October 2011.1. Scope1.
3、1 This specification contains reference tables (Tables 8 to 25) that give temperature-electromotive force (emf) relationshipsfor Types B, E, J, K, N, R, S, T, and C thermocouples.2 These are the thermocouple types most commonly used in industry. Thetables contain all of the temperature-emf data curr
4、ently available for the thermocouple types covered by this standard and mayinclude data outside of the recommended upper temperature limit of an included thermocouple type.1.2 In addition, the specification includes standard and special tolerances on initial values of emf versus temperature fortherm
5、ocouples (Table 1), thermocouple extension wires (Table 2), and compensating extension wires for thermocouples (Table 3).Users should note that the stated tolerances apply only to the temperature ranges specified for the thermocouple types as given inTables 1, 2, and 3, and do not apply to the tempe
6、rature ranges covered in Tables 8 to 25.1.3 Tables 4 and 5 provide insulation color coding for thermocouple and thermocouple extension wires as customarily used inthe United States.1.4 Recommendations regarding upper temperature limits for the thermocouple types referred to in 1.1 are provided in Ta
7、ble 6.1.5 Tables 26 to 45 give temperature-emf data for single-leg thermoelements referenced to platinum (NIST Pt-67). The tablesinclude values for Types BP, BN, JP, JN, KP (same as EP), KN, NP, NN, TP, and TN (same as EN).1.6 Tables for Types RP, RN, SP, and SN thermoelements are not included since
8、, nominally, Tables 18 to 21 represent thethermoelectric properties of Type RP and SP thermoelements referenced to pure platinum. Tables for the individual thermoelementsof Type C are not included because materials for Type C thermocouples are normally supplied as matched pairs only.1.7 Polynomial c
9、oefficients which may be used for computation of thermocouple emf as a function of temperature are given inTable 7. Coefficients for the emf of each thermocouple pair as well as for the emf of most individual thermoelements versusplatinum are included. Coefficients for type RP and SP thermoelements
10、are not included since they are nominally the same as fortypes R and S thermocouples, and coefficients for type RN or SN relative to the nominally similar Pt-67 would be insignificant.Coefficients for the individual thermoelements of Type C thermocouples have not been established.1.8 Coefficients fo
11、r sets of inverse polynomials are given in Table 46. These may be used for computing a close approximationof temperature (C) as a function of thermocouple emf. Inverse functions are provided only for thermocouple pairs and are validonly over the emf ranges specified.1.9 This specification is intende
12、d to define the thermoelectric properties of materials that conform to the relationships presentedin the tables of this standard and bear the letter designations contained herein. Topics such as ordering information, physical andmechanical properties, workmanship, testing, and marking are not addres
13、sed in this specification. The user is referred to specificstandards such as Specifications E235, E574, E585/E585M, E608/E608M, E1159, or E2181/E2181M for guidance in these areas.1.10 The temperature-emf data in this specification are intended for industrial and laboratory use.1.11 Thermocouple colo
14、r codes per IEC 5843 are given in Appendix X1.1 These tables are under the jurisdiction of ASTM Committee E20 on Temperature Measurement and are the direct responsibility of Subcommittee E20.04 onThermocouples.Current edition approved May 15, 2011Nov. 1, 2012. Published October 2011November 2012. Or
15、iginally approved in 1963. Last previous edition approved in 20032011as E230 03.E230 111. DOI: 10.1520/E0230_E0230M-11E01.10.1520/E0230_E0230M-12.2 These temperature-emf relationships have been revised as required by the international adoption in 1989 of a revised International Temperature Scale (IT
16、S-90).This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult pri
17、or editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States11.12 The values stated in either SI units
18、or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from thetwo systems may result in non-conformance with the standard.1.12.1 The values stated
19、in brackets are not conversions to the values they succeed and therefore shall be used independentlyof the preceding values.1.12.2 The values given in parentheses are conversions of the values they succeed.1.12.3 Combining values from the two systems may result in non-conformance with the standard.1
20、.13 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Doc
21、uments2.1 ASTM Standards:3E235 Specification for Thermocouples, Sheathed, Type K and Type N, for Nuclear or for Other High-Reliability ApplicationsE574 Specification for Duplex, Base Metal Thermocouple Wire With Glass Fiber or Silica Fiber InsulationE585/E585M Specification for Compacted Mineral-Ins
22、ulated, Metal-Sheathed, Base Metal Thermocouple CableE608/E608M Specification 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,
23、 Noble Metal Thermocouples and Thermo-couple Cable2.2 NIST Monograph:NIST Monograph 175 Temperature-Electromotive Force Reference Functions and Tables for the Letter-Designated Thermo-couple Types Based on the ITS-9042.3 IEC Standard:IEC 5843 Thermocouples Part 3: Extension and Compensating Cables T
24、olerances and Identification System, 19893. Source of Data3.1 The data in these tables are based upon the SI volt5 and the 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 46 forall
25、 thermocouple types except Type C, have been extracted from NIST Monograph 175. Temperature-emf data in Tables 24 and25 and the coefficients for Type C in Tables 7 and 46 have been developed from curves fitted to wire manufacturers data.NOTE 1It is beyond the scope of this standard to discuss the or
26、igin of these tables. If further information is required, the reader should consult NISTMonograph 175.3.3 These tables give emf values to three decimal places (1 V) at temperature intervals of one degree. The tables aresatisfactory for most industrial uses but may not be adequate for computer and si
27、milar applications. If greater precision is required,the reader should refer to NIST Monograph 175 which includes tables giving emf values to four decimal places (0.1 V) for eachtype except Type C. Equations which permit easy and unique generation of the temperature-emf relationships can be found in
28、Table 7. For convenience, coefficients of inverse polynomials that may be used to calculate approximate temperature (C) as afunction of thermocouple emf are given in Table 46.4. Thermocouple Types and Letter Designations4.1 The letter symbols identifying each reference table are those which are in c
29、ommon use throughout industry and identify thefollowing thermocouple calibrations:4.1.1 Type 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 (constantan) ().4.1.4 T
30、ype KNickel-10 % chromium (+) versus nickel-5 % (aluminum, silicon) ().NOTE 2Silicon, or aluminum and silicon, may be present in combination 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 (+) ve
31、rsus platinum ().4.1.7 Type SPlatinum-10 % rhodium (+) versus platinum ().4.1.8 Type TCopper (+) versus copper-45 % nickel (constantan) ().3 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolu
32、me information, refer to the standards Document Summary page on the ASTM website.4 Available from National Institute of Standards and Technology (NIST), 100 Bureau Dr., Stop 1070, Gaithersburg, MD 20899.5 Discussed in NIST Technical Note 1263, Guidelines for Implementing the New Representations of t
33、he Volt and Ohm Effective January 1, 1990.E230/E230M 1224.1.9 Type CTungsten-5 % Rhenium (+) versus Tungsten-26 % Rhenium ().4.2 Each letter designation in 4.1 identifies a specific temperature-emf relationship (Tables 8 to 25) and may be applied to anythermocouple conforming thereto within stated t
34、olerances on initial values of emf versus temperature, regardless of itscomposition.4.3 The thermoelement identifying symbols in Tables 26 to 45 use the suffix letters P and N to denote, respectively, the positiveand negative thermoelement of a given thermocouple type.4.4 Tables 26 to 45 identify sp
35、ecific temperature-emf relationships of individual thermoelements with respect to platinum (NISTPt-67). The appropriate letter designation may be applied to any thermoelement which, when combined with its matingthermoelement, will form a thermocouple conforming to the corresponding table within the
36、stated tolerances.4.5 An overall suffix letter “X” (for example KX, TX, EPX, JNX) denotes an “extension grade” material whose thermoelectricproperties will match those of the corresponding thermocouple type within the stated extension grade tolerances over a limitedtemperature range. Most base metal
37、 extension wires have the same nominal composition as the thermocouple wires with whichthey are intended to be used, whereas the compensating extension wires for noble metal or refractory metal thermocouple types(S, R, B, or C) are usually of a different, more economical composition whose relative t
38、hermoelectric properties as a pairnonetheless closely approximate those of the noble metal or refractory metal thermocouples with which they are to be used overa limited temperature range.5. Tolerances on Initial Values of Emf versus Temperature5.1 In the United States, thermocouples and matched the
39、rmocouple wire pairs are normally supplied conforming to thetolerances on initial values of emf versus temperature provided in Table 1.5.1.1 Tolerances on initial values of emf versus temperature for single-leg thermoelements referenced to platinum have beenestablished only for Types KP and KN. Thes
40、e are supplied, by common practice, to a tolerance equivalent to one half the millivolttolerance of the Type K thermocouple.5.1.2 For all other thermocouple types, tolerances on initial values of emf versus temperature for single thermoelements shouldbe established by agreement between the purchaser
41、 and the supplier.5.1.3 In Tables 34, 35, 44, and 45, the thermoelements are identified by two thermoelement symbols indicating theirapplicability to two thermocouple types. This indicates that the temperature-electromotive force relationship of the table is typicalof the referenced thermoelements o
42、ver the temperature range given in Table 1 for the corresponding thermocouple type. It shouldnot be assumed, however, that thermoelements used with one thermocouple type are interchangeable with those of the other, orthat they have the same millivolt tolerances for the initial values of emf versus t
43、emperature.5.2 Thermocouple extension wires and compensating extension wires are supplied to conform to the tolerances on initial valuesof emf versus temperature shown in Tables 2 and 3, respectively.5.2.1 Initial tolerances of extension grade materials and compensating extension materials apply ove
44、r a more limited range oftemperature than the corresponding thermocouple grade materials. Applicable temperature ranges, consistent with typical usage,are given in Tables 2 and 3.6. Color Coding6.1 Color codes for insulation on thermocouple grade materials, along with corresponding thermocouple and
45、thermoelementletter designations, are given in Table 4.6.2 Extension wires for thermocouples are distinguished by having an identifying color in the outer jacket as shown in Table 5,where letter designations for the extension thermoelements and pairs are also presented.6.3 Information presented in T
46、ables 4 and 5 is based on customary practice in the United States.NOTE 3Other insulation color coding conventions may be found in use elsewhere in the world. Refer to Appendix X1 for information.E230/E230M 1237. List of Tables7.1 Following is a list of the tables included in this standard:7.1.1 Gene
47、ral Tables:TableNumberTitle1 Tolerances on Initial Values of Emf versus Temperature forThermocouples2 Tolerances on Initial Values of Emf versus Temperature forExtension Wires3 Tolerances on Initial Values of Emf versus Temperature forCompensating Extension Wires4 United States Color Codes for Singl
48、e and Duplex InsulatedThermocouple Wire5 United States Color Codes for Single and Duplex InsulatedExtension Wire6 Suggested Upper Temperature Limits for ProtectedThermocouples7 Polynomial Coefficients for Generating Thermocouple Emf as aFunction of Temperature7.1.2 Emf versus Temperature Tables for
49、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 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 Type Thermoele-ment Type TemperatureRangeA26 B BP 0 to 1768C27 B BP 32 to 3214F28 B
