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TM_D_4245_
_08_2013
Designation:D424508(Reapproved 2013)Standard Specification forOzone-Resistant Thermoplastic Elastomer Insulation ForWire and Cable,90C Dry/75C Wet Operation1This standard is issued under the fixed designation D4245;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of 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 specification covers an ozone-resistant insulatingcompound for electrical wire and cables 14 AWG and larger.This compound consists substantially of a thermoplastic elas-tomer.1.2 This type of insulation is suitable for continuous opera-tion at conductor temperatures not exceeding 90C in drylocations and 75C in wet locations.Operating voltages are notto exceed 2000 V.The minimum installation temperatureis 40C.1.3 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.4In many instances the insulation material cannot betested unless it has been formed around a conductor or cable.Therefore,tests are done on insulated wire or cable in thisdocument solely to determine the relevant property of theinsulation material and not to test the conductor or completedcable.2.Referenced Documents2.1 ASTM Standards:2D470 Test Methods for Crosslinked Insulations and Jacketsfor Wire and CableD1711 Terminology Relating to Electrical InsulationD2633 Test Methods for Thermoplastic Insulations andJackets for Wire and Cable3.Terminology3.1 Definitions:For definitions of terms used in this speci-fication refer to Terminology D1711.3.2 Definitions of Terms Specific to This Standard:3.2.1 aging,nexposure of materials to air at 121 C for168 h.4.Physical Properties4.1 Requirements for physical properties are listed in Table1.4.2 Thickness of InsulationTable 1A(Conductor Sizes,Insulation Thicknesses,and AC Test Voltages for RubberInsulations)of Test Methods D470 lists the minimum averagethickness for the insulation.The required minimum thicknessis 90%of the specified average thickness.5.Electrical Requirements5.1 Order of TestingPerform the ac voltage withstand test,insulation resistance,and dc voltage withstand test in that orderwhen any of these tests are specified.The sequence of othertesting is not specified.5.2 AC Voltage Withstand TestUnless otherwise specified,omit this test if the dc voltage withstand test described in 5.4 isto be performed.Test each insulated conductor for 5 min at theac withstand voltage given in Table 1A(Conductor Sizes,Insulation Thicknesses,and AC Test Voltages for RubberInsulations)of Test Methods D470 under the columns labeled“Ozone-Resisting Insulation.”5.3 Insulation Resistance5.3.1 The insulated conductor shall have an insulationresistance value of at least that corresponding to a constant of10 000 at 60F(15.6C).5.3.2 If the water temperature at the time measurement wasmade differs from 60F(15.6C),correct the insulation resis-tance to 60F.Table 2,(Temperature Correction Factors forInsulation Resistance at 60F),of Test Methods D470,containsthe correction factors.Use the procedure given in Test MethodsD470 to determine the 1F coefficient for the insulationmaterial.Multiply the measured value by the correction factorto obtain the insulation resistance value corrected to 60F.5.3.3 If the insulated conductor is covered with a non-metallic sheath so that the insulation resistance can be mea-sured only on the completed assembly,the required insulationresistance shall be not less than 60%of that required for theprimary insulation based on the thickness of that insulation.1This specification is under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and is the direct responsibility ofSubcommittee D09.18 on Solid Insulations,Non-Metallic Shieldings and Coveringsfor Electrical and Telecommunication Wires and Cables.Current edition approved Nov.1,2013.Published December 2013.Originallyapproved in 1983.Last previous edition approved in 2008 as D4245 08.DOI:10.1520/D4245-13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.*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 5.4 DC Voltage Withstand TestUnless otherwise specified,omit this test if the ac voltage withstand test described in 5.2has been performed.After completion of the insulation resis-tance test,test each insulated conductor for 5 min at the dcwithstand voltage given in Table 1B(Conductor Sizes,and DCTest Voltages for Rubber Insulations)of Test