1、Designation:D230721Standard 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 last revision.A nu
2、mber 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 pressure.It is not ap
3、plicable 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 wire insulationrequi
4、res 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 wheninterpreting the results obta
5、ined 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 endur-ance of film
6、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-pound units are to
7、be regardedas the standard.The SI units in parentheses are provided forinformation only and are not considered standard.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-priat
8、e safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment
9、 of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1676 Test Methods for Film-Insulated Magnet WireD1711 Terminology Relating to Electrical InsulationD3251 Test Method for
10、Thermal Endurance Characteristicsof Electrical Insulating Varnishes Applied Over Film-Insulated Magnet WireD5423 Specification for Forced-Convection Laboratory Ov-ens for Evaluation of Electrical Insulation2.2 Other Standards:IEC 60172 Test Procedure For The Determination Of TheTemperature Index Of
11、Enamelled Winding Wires3IEEE 101 Guide for the Statistical Analysis of Thermal LifeTest Data43.Terminology3.1 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,based
12、on the temperature in degrees Celsius which is obtained byextrapolating the Arrhenius plot of life versus 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 a
13、t elevated temperatures for ex-tended periods of time.3.2 Definitions of Terms Specific to This Standard: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 Fire and Thermal Prope
14、rties.Current edition approved July 1,2021.Published August 2021.Originallyapproved in 1964.Last previous edition approved in 2013 as D2307 07a(2013).DOI:10.1520/D2307-212For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual B
15、ook of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from International Electrotechnical Commission(IEC),3,rue deVaremb,1st floor,P.O.Box 131,CH-1211,Geneva 20,Switzerland,https:/www.iec.ch.4Available from Institute of Electrical and Elec
16、tronics Engineers,Inc.(IEEE),445 Hoes Ln.,Piscataway,NJ 08854-4141,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 StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued b