1、Designation:D230707a(Reapproved 2013)Standard Test Method forThermal Endurance of Film-Insulated Round Magnet Wire1This standard is issued under the fixed designation D2307;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of
2、last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers determination of the thermalendurance of film-insulated round magnet wire in air atatmospheric pre
3、ssure.It is not applicable to magnet wire withfibrous insulation,such as cotton or glass.1.2 This test method covers the evaluation of thermalendurance by observing changes in response to ac proofvoltage tests.The evaluation of thermal endurance by observ-ing changes in other properties of magnet wi
4、re insulationrequires the use of different test methods.1.3 It is possible that exposure of some types of filminsulated wire to heat in gaseous or liquid environments in theabsence of air will give thermal endurance values differentfrom those obtained in air.Consider this possibility wheninterpretin
5、g the results obtained by heating in air with respectto applications where the wire will not be exposed to air inservice.1.4 It is possible that electric stress applied for extendedperiods at a level exceeding or even approaching the dischargeinception voltage will change significantly the thermal e
6、ndur-ance of film insulated wires.Under such electric stressconditions,it is possible that comparisons between materialswill also differ from those developed using this method.1.5 This test method is similar to IEC 60172.Differencesexist regarding specimen preparation.1.6 The values stated in inch-p
7、ound units are to be regardedas the standard.The SI units in parentheses are provided forinformation only.1.7 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and h
8、ealth practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1676 Test Methods for Film-Insulated Magnet WireD1711 Terminology Relating to Electrical InsulationD3251 Test Method for Thermal Endurance Characteristicsof Electrical I
9、nsulating Varnishes Applied Over Film-Insulated Magnet WireD5423 Specification for Forced-Convection Laboratory Ov-ens for Evaluation of Electrical Insulation2.2 Other Standards:IEC 60172 Statistical Analysis of Thermal Life Test Data3IEEE 101 Statistical Analysis of Thermal Life Test Data43.Termino
10、logy3.1 Definitions:3.1.1 temperature index,na number which permits com-parison of the temperature/time characteristics of an electricalinsulating material,or a simple combination of materials,basedon the temperature in degrees Celsius which is obtained byextrapolating the Arrhenius plot of life ver
11、sus temperature to aspecified time,usually 20 000 h.3.1.2 thermal endurance,nan expression for the stabilityof an electrical insulating material,or a simple combination ofmaterials,when maintained at elevated temperatures for ex-tended periods of time.3.2 Definitions of Terms Specific to This Standa
12、rd:3.2.1 specimen failure time,nthe hours at the exposuretemperature that have resulted in a specimen failing the prooftest(see 9.1).3.2.2 thermal endurance cycle,none oven exposure pe-riod followed by a proof voltage test.3.2.3 time to failure,nthe log average hours calculated fora set of specimens
13、,calculated from the individual specimenfailure times at an exposure temperature(see 9.2).1This test method is under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and is the direct responsibility ofSubcommittee D09.17 on Thermal Characteristics.Current editi
14、on approved April 1,2013.Published April 2013.Originallyapproved in 1964.Last previous edition approved in 2007 as D2307 07a.DOI:10.1520/D2307-07AR13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards
15、 volume information,refer to the standards Document Summary page onthe ASTM website.3Available from International Electrotechnical Commission(IEC),3 rue deVaremb,Case postale 131,CH-1211,Geneva 20,Switzerland,http:/www.iec.ch.4Available from Institute of Electrical and Electronics Engineers,Inc.(IEE
16、E),445 Hoes Ln.,P.O.Box 1331,Piscataway,NJ 08854-1331,http:/www.ieee.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.3 For definitions of terms related to electrical insulation,see Terminology D1711.4.Summary of Test Method4.1 This test method specifies the preparation of specimens,the exposure of these specimens at elevated temperatures,andthe periodic testing of
