1、Designation: E230/E230M 12E230/E230M 17 An American National StandardStandard Specification forTemperature-Electromotive Force (emf) Tables forStandardized Thermocouples1This standard is issued under the fixed designation E230/E230M; the number immediately following the designation indicates the yea
2、rof 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. Scope1.1 This specification contains reference tables (Tables 8
3、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 currently available for the thermocouple types covered by thi
4、s 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 forthermocouples (Table 1), thermocouple extension wires (Table 2
5、), 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 temperature ranges covered in Tables 8 to 25.1.3 Tables 4 and
6、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 Table 6.1.5 Tables 26 to 45 give temperature-emf data for s
7、ingle-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, nominally, Tables 18 to 21 represent thethermoelectric
8、properties ofType RPand SPthermoelements 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 coefficients which may be used for computation of thermocouple
9、 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 are not included since they are nominally the same as fortype
10、s 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 for sets of inverse polynomials are given in Table 46. These ma
11、y 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 intended to define the thermoelectric properties of materials that c
12、onform 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 addressed in this specification. The user is referred to specificst
13、andards 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 color codes per IEC 5843 are given in Appendix X1.1.12 The values
14、 stated in either SI units or inch-pound units are to be regarded separately as standard.1.12.1 The values stated in brackets are not conversions to the values they succeed and therefore shall be used independentlyof the preceding values.1 This specification is under the jurisdiction of ASTM Committ
15、ee E20 on Temperature Measurement and are the direct responsibility of Subcommittee E20.11 onThermocouples - Calibration.Current edition approved Nov. 1, 2012Nov. 1, 2017. Published November 2012November 2017. Originally approved in 1963. Last previous edition approved in 20112012as E230 11E230/E230
16、M 12.1. DOI: 10.1520/E0230_E0230M-12.10.1520/E0230_E0230M-17.2 These temperature-emf relationships have been revised as required by the international adoption in 1989 of a revised International Temperature Scale (ITS-90).This document is not an ASTM standard and is intended only to provide the user
17、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 prior editions as appropriate. In all cases only the current versionof the standard as p
18、ublished 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 States11.12.2 The values given in parentheses are conversions of the values they succeed.1.12.3 Combining values from the two systems
19、may result in non-conformance with the standard.1.13 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 reg
20、ulatorylimitations prior to use.1.14 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Orga
21、nization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 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 Sil
22、ica Fiber InsulationE585/E585M Specification for Compacted Mineral-Insulated, 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
23、/E2181M Specification for Compacted Mineral-Insulated, Metal-Sheathed, 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 Stand
24、ard:IEC 5843 Thermocouples Part 3: Extension and Compensating Cables Tolerances 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 4
25、5, together with the corresponding equations in Tables 7 and 46 forall 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 manufacturer
26、s data.NOTE 1It is beyond the scope of this standard to discuss the origin 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 aresatisfactor
27、y for most industrial uses but may not be adequate for computer and similar 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
28、unique generation of the temperature-emf relationships can be found inTable 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 le
29、tter symbols identifying each reference table are those which are in common 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) ().
30、4.1.3 Type JIron (+) versus copper-45 % nickel (constantan) ().4.1.4 Type 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
31、 % 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 TCopper (+) versus copper-45 % nickel (constantan) ().4.1.9 Type CTungsten-5 % Rhenium (+) versus Tungsten-26 % Rhenium ().3 For referencedASTM s
32、tandards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4 Available from National Institute of Standards and Technology (NIST), 100 Bureau
33、Dr., Stop 1070, Gaithersburg, MD 20899.5 Discussed in NIST Technical Note 1263, Guidelines for Implementing the New Representations of the Volt and Ohm Effective January 1, 1990.E230/E230M 1724.2 Each letter designation in 4.1 identifies a specific temperature-emf relationship (Tables 8 to 25) and m
34、ay be applied to anythermocouple conforming thereto within stated tolerances 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 thermoe
35、lement of a given thermocouple type.4.4 Tables 26 to 45 identify specific 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 fo
36、rm a thermocouple conforming to the corresponding table within the 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 extensio
37、n grade tolerances over a limitedtemperature range. Most base metal 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 u
38、sually of a different, more economical composition whose relative thermoelectric 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
39、 Temperature5.1 In the United States, thermocouples and matched thermocouple 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 referen
40、ced to platinum have beenestablished only for Types KP and KN. These 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 the
41、rmoelements shouldbe established by agreement between the purchaser 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 rel
42、ationship of the table is typicalof the referenced thermoelements over 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 t
43、he same millivolt tolerances for the initial values of emf versus temperature.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 exten
44、sion grade materials and compensating extension materials apply over 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 therm
45、ocouple grade materials, along with corresponding thermocouple and 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 thermoe
46、lements and pairs are also presented.6.3 Information presented in Tables 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.7. List of Tables7.1 Following is a li
47、st of the tables included in this standard:7.1.1 General Tables:Table Number Title1 Tolerances on Initial Values of Emf versus Temperature for Thermocouples2 Tolerances on Initial Values of Emf versus Temperature for Extension Wires3 Tolerances on Initial Values of Emf versus Temperature for Compens
48、ating Extension Wires4 United States Color Codes for Single and Duplex Insulated Thermocouple Wire5 United States Color Codes for Single and Duplex Insulated Extension Wire6 Suggested Upper Temperature Limits for Protected Thermocouples7 Polynomial Coefficients for Generating Thermocouple Emf as a F
49、unction of Temperature7.1.2 Emf versus Temperature Tables for Thermocouples:Table Number Thermocouple Type Temperature RangeAE230/E230M 1738 B 0 to 1820C8 B 0 C to 1820 C9 B 32 to 3308F9 B 32 F to 3308 F10 E 270 to 1000C10 E -270 C to 1000 C11 E 454 to 1832F11 E -454 F to 1832 F12 J 210 to 1200C12 J -210 C to 1200 C13 J 346 to 2192F13 J -346 F to 2192 F14 K 270 to 1372C14 K -270 C to 1372 C15 K 454 to 2500F15 K -454 F to 2500 F16 N 270 to 1300C16 N -270 C to 1300 C17 N 454 to 2372F17 N -454 F to 2372 F18 R 5
