1、Designation: E3137/E3137M 17Standard Specification forHeat Meter Instrumentation1,2This standard is issued under the fixed designation E3137/E3137M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revision. A numbe
2、r 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 defines general specifications for heatmeters. Heat meters are instruments that measure heat in heatexchange circuits in
3、which energy is absorbed (cooling) orgiven up (heating) by a flowing liquid.1.2 For this specification, the necessary elements of a heatmeter consist of a sensor to measure flow of the heat-conveyingliquid, a pair of temperature sensors that measure the tempera-ture differential across the heat exch
4、ange circuit, and a devicethat receives input from the flow and temperature sensors andcalculates energy.1.3 Electrical safety is not a part of this specification.1.4 Mechanical safety (including pressure safety) is not apart of this specification.1.5 The values stated in either SI units or inch-pou
5、nd unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in nonconformancewith the standard.1.6 This standard does not purport to ad
6、dress all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.7 This international standard was dev
7、eloped in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Do
8、cuments2.1 CCT Standard:3ITS-90 International Temperature Scale of 19902.2 IAPWS Standard:4IAPWS-IF97 Industrial Formulation 1997 for the Thermo-dynamic Properties of Water and Steam2.3 IEC Standards:5IEC 61000 Part 4-2 Electrostatic Discharge Immunity TestIEC 61000 Part 4-3 Radiated, Radio-Frequenc
9、y, Electro-magnetic Field Immunity TestIEC 61000 Part 4-4 Electrical Fast Transient/Burst ImmunityTestIEC 61000 Part 4-5 Surge Immunity TestIEC 60068: Environmental Testing Part 2.1 Test A: ColdIEC 60068: Environmental Testing Part 2.2 Tests B: DryHeatIEC 60068: Environmental Testing Part 2-30 Tests
10、 Db:Damp Heat, cyclicIEC 60529 Degrees of protection provided by enclosures (IPCode)IEC 60751 Industrial platinum resistance thermometer andplatinum temperature sensorsIEC 60870 Part 5-1 Telecontrol equipment and systemsIEC 61107 Data exchange for meter reading, tariff and loadcontrolDirect local da
11、ta exchangeIEC TR 61000 Electromagnetic compatibilityPart 2:EnvironmentSection 7: Low frequency magnetic fieldsin various environments2.4 NEMA Standards:6NEMA 250 Enclosures for Electrical Equipment (1000 VoltsMaximum)2.5 OIML Standards:7OIML D11 General Requirements for measuringinstrumentsEnvironm
12、ental conditionsOIML R 49 Part 2 Water meters intended for the metering ofcold potable water and hot water1This specification is under the jurisdiction of ASTM Committee E44 on Solar,Geothermal and Other Alternative Energy Sources and is the direct responsibility ofSubcommittee E44.25 on Heat Meteri
13、ng.Current edition approved Nov. 1, 2017. Published December 2017. DOI:10.1520/E3137_E3137M17.2Through a mutual agreement with ASTM International (ASTM), the Interna-tional Association of Plumbing and Mechanical Officials (IAPMO) contributed itstechnical expertise to ASTM, leading to the development
14、 of this ASTM Stan-dard. IAPMO and its membership continue to play an active role in providingtechnical guidance to the ASTM standards development process.3Available from the Consultative Committee for Thermometry, www.its-.4Available from the International Association for the Properties of Water an
15、dSteam, www.iapws.org.5Available from the International Electrotechnical Commission, www.iec.ch.6Available from National Electrical Manufacturers Association (NEMA), 1300N. 17th St., Suite 900, Arlington, VA 22209, http:/www.nema.org.7Available from the International Organization of Legal Metrology,
16、www.oiml.org/en.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDeve
17、lopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1OIML R75-1 Part 1 General requirements3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 conventional true value, nvalue of a quantit
18、y, whichfor the purpose of this specification, is considered as a truevalue. OIML R75-1 20023.1.1.1 DiscussionA conventional true value is regarded,in general, as sufficiently close to the true value for thedifference to be insignificant for the given purpose. OIMLR75-1 20023.1.2 disturbance, ninflu
19、ence quantity having a valueoutside the rated operating conditions. OIML R75-1 20023.1.3 electronic device, ndevice using electronic compo-nents and performing a specific function. OIML R75-1 20023.1.4 equipment under test, nsubassembly, a combinationof subassemblies, or a complete meter subject to
20、a test. OIMLR75-1 20023.1.5 error types, n3.1.5.1 durability error, ndifference between the intrinsicerror after a period of use and the initial intrinsic error. OIMLR75-1 20023.1.5.2 error (of indication) of a measuring instrument,nindication of the measuring instrument minus the conven-tional true
21、 value of the corresponding input quantity. OIMLR75-1 20023.1.5.3 initial intrinsic error, nintrinsic error of a measur-ing instrument as determined before performance and durabil-ity tests.3.1.5.4 intrinsic error (of a measuring instrument), nerrorof a measuring instrument determined under referenc
22、econditions. OIML R75-1 20023.1.5.5 maximum permissible error, MPE, nextreme val-ues of the error (positive or negative) permitted by thisspecification. OIML R75-1 20023.1.6 fast response meter, nheat meter designed for use inheat exchange circuits in which sudden or rapid changes, orboth, in flow o
23、r temperature are a normal condition. OIMLR75-1 20023.1.7 fault types, n3.1.7.1 fault, ndifference between the error of indicationand the intrinsic error of the instrument. OIML R75-1 20023.1.7.2 significant faultfault greater than the absolutevalue of the MPE that is not a transitory fault, for exa
24、mple, ifthe MPE is 62 %, then a significant fault is a fault larger than2%. OIML R75-1 20023.1.7.3 transitory faultmomentary variations in the indi-cation that cannot be interpreted, memorized, or transmitted asmeasurements. OIML R75-1 20023.1.8 flow direction, nindication of directionality for aflo
25、wing liquid within a piping system leading to and exitingfrom a heat exchange circuit.3.1.8.1 DiscussionThe term supply (or inlet) is used toindicate liquid traveling to the heat exchanger and the termreturn (or outlet) describes the liquid exiting the heat ex-changer. In heating systems, supply liq
26、uids will normally havea higher temperature than return liquids. In cooling systems,supply liquids will normally have a lower temperature thanreturn liquids.3.1.9 flow sensor, nsubassembly of a heat meter designedto measure the volume or mass of a flowing liquid in a heatexchange circuit.3.1.10 heat
27、 calculator, nheat meter subassembly that re-ceives flow and temperature signals from flow and temperaturesensors and calculates and displays energy.3.1.11 influence factor, ninfluence quantity having a valuewithin the rated operating conditions. OIML R75-1 20023.1.12 influence quantity, nquantity t
28、hat is not the mea-surand but that affects the result of the measurement. OIMLR75-1 20023.1.13 meter model, ndifferent sizes of heat meters orsubassemblies having a family similarity in the principles ofoperation, construction, and materials. OIML R75-1 20023.1.14 minimum immersion depth of a temper
29、ature sensor,ndepth of immersion in a thermostatic bath with a tempera-ture of 80 6 5C 176 6 9F at an ambient temperature of25 6 5C 77 6 9F, beyond which deeper immersionchanges the output value by an amount corresponding to lessthan 0.1 K 0.18F. OIML R75-1 20023.1.15 platinum resistance thermometer
30、, PRT,ntemperature responsive device consisting of one or moresensing platinum resistors within a protective sheath withinternal connecting wires and external terminals to permitconnection of electrical measurement instruments.3.1.15.1 DiscussionMounting means and connectionheads may be included. No
31、t included is any separable protec-tion tube or thermowell.3.1.16 platinum resistor, nresistor made from platinumwire or film with defined electrical characteristics, embeddedin an insulator (in most cases glass or ceramic), designed to beassembled into a resistance thermometer or an integratedcircu
32、it.3.1.17 rated operating conditions, nconditions of use forwhich specified metrological characteristics of a measuringinstrument are intended to lie within the specified maximumpermissible errors. OIML R75-1 20023.1.18 rated voltage, Un,nvoltage of an external powersupply required to operate a heat
33、 meter.3.1.19 reference conditions, nconditions of use prescribedfor testing the performance of a measuring instrument orintercomparison of results of measurements. OIML R75-120023.1.20 reference values of the measurand, RVM,nspecified set of values of the flow rate, the returntemperature, and the t
34、emperature difference fixed to ensurevalid intercomparison of the results of measurements. OIMLR75-1 20023.1.21 response time, 0.5, ntime interval between theinstant when the flow, the temperature, or the temperaturedifference is subjected to a specified abrupt change and theE3137/E3137M 172instant
35、when the response reaches 50 % of its final steadyvalue. OIML R75-1 20023.1.22 self-heating effect, nincrease in temperature signalthat is obtained by subjecting each temperature sensor of a pairto a continuous power dissipation of 5 mW when immersed tothe minimum immersion depth in a water bath hav
36、ing a meanwater velocity of 0.1 m/s 0.328 ft/s. OIML R75-1 20024. Significance and Use4.1 This document is based, in part, on OIML R 75-1Edition 2002, Heat meters Part 1: General requirements andOIML R 75-2 Edition 2002, Heat meters Part 2: Type approvaltests and initial verification tests. R 75 is
37、an InternationalRecommendation published by OIML. International Recom-mendations are model regulations that establish the metrologi-cal characteristics required of certain measuring instrumentsand which specify methods and equipment for checking theirconformity. As an OIML Member State, The United S
38、tates isobligated to utilize these recommendations, where possible,when developing standards that meet the needs of the marketand may result in either terminology or definitions specific tothis standard and deviations in standard form and style.5. Using this Specification5.1 This specification is in
39、tended to provide both manufac-turers and users of heat meters with important information.5.2 Manufacturers will use this specification to certify thattheir products conform to industry standards for accuracy,performance, and reliability.5.3 End users and specifying engineers will use this speci-fic
40、ation as a guide in understanding how heat meters aredefined based on performance and accuracy classifications forflow, temperature, and energy. They will also use this specifi-cation to ensure that the meter will be suitable for use in theoperating environment in which it will be installed.5.4 End
41、users are strongly encouraged to review carefullythe requirements of their specific application and then select aheat meter that will meet their needs based on the followingcriteria:5.4.1 Flow Sensor Accuracy ClassClass 1, Class 2, orClass 3;5.4.2 Lower Limit of the Temperature Difference Range1,2,
42、or 3 K 1.8, 3.6, or 5.4F; and5.4.3 Environmental ClassA, B, C, or D.5.5 Overall accuracy of the heat meter is defined as theadditive maximum permissible errors (MPE) of the flowsensor, the temperature sensor pair, and the heat calculator. SeeSection 7 for additional information on maximum permissibl
43、eerrors.5.6 Flow Sensors:5.6.1 The three flow sensor accuracy classes are Class 1,Class 2, or Class 3. In each class, the accuracy is determined bythe MPE at the manufacturers stated minimum (Qi) andmaximum permanent flow rate (Qp). See 8.2 for additionalinformation on flow sensor operating limits.5
44、.6.2 The MPE for each flow sensor varies with the flowsensor accuracy class and the ratio of the Qpto the actualoperating flow rate (Q). This is the turndown for the sensor.When selecting a flow sensor, it is necessary to identify first themaximum flow rate for the application. This maximum flowrate
45、 shall be compared to the upper flow limit (Qs) and the Qpas stated by the flow meter manufacturer for the flow sensorunder consideration. Next, identify the minimum flow rate forthe application. Compare this value to the Qias stated by theflow meter manufacturer. Flow sensors should be selected tha
46、twill operate within these upper and lower flow limits. Once theupper and lower flow limits are defined (turndown), theaccuracy limits by class can be determined from Table 1.5.6.3 Table 1 shows the range of allowable error (Ef) for theflow sensor by class and turndown range for use in MPEequations
47、in 8.3. For clarity, turndown is expressed as Qp/QiinTable 1.5.7 Temperature Sensor Pairs and Heat Calculator:5.7.1 The MPE of the temperature sensor pair is a functionof the lower limit of the temperature difference as described in9.4 and 9.5. The three lower limits for the temperaturedifference ra
48、nge are 1, 2, and 3 K 1.8, 3.6, or 5.4F. As withthe flow sensor, the highest percentage measurement error willoccur at the minimum operating level. In this case, it is thelowest differential temperature.5.7.2 The heat calculator MPE is also defined by the lowerlimit of the temperature difference ran
49、ge (1, 2, or 3 K) asdescribed in 10.4. As is the case with the temperature sensorpair, the highest percentage measurement error will occur at theminimum temperature differential.5.7.3 When selecting a temperature sensor pair, it is neces-sary to identify the minimum and maximum operating tem-peratures for the application and confirm that they fall withinthe operating limits of the individual temperature sensors.Next, identify and compare the maximum and minimumtemperature difference for the application with the upper l
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