1、Designation: D 4245 02An American National StandardStandard Specification forOzone-Resistant Thermoplastic Elastomer Insulation ForWire and Cable, 90C Dry/75C Wet Operation1This standard is issued under the fixed designation D 4245; the number immediately following the designation indicates the year
2、 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers an ozone-resistant insulating
3、compound 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
4、notto exceed 2000 V. The minimum installation temperatureis 40C.1.3 Whenever two sets of values are presented, in differentunits, the values in the first set are the standard, while those inparentheses are for information only.1.4 In many instances the insulation material cannot betested unless it h
5、as 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:D 470 Test Methods for Crossli
6、nked Insulations and Jacketsfor Wire and Cable2D 1711 Terminology Relating to Electrical Insulation2D 2633 Methods of Testing Thermoplastic Insulations andJackets for Wire and Cable33. Terminology3.1 Definitions: For definitions of terms used in this speci-fication refer to Terminology D 1711.3.2 De
7、finitions of Terms Specific to This Standard:3.2.1 aging, nexposure of materials to air at 121C for168 h.4. Physical Properties4.1 Requirements for physical properties are listed in Table1.4.2 Thickness of InsulationTable 1(a) (Conductor Sizes,Insulation Thicknesses, and AC Test Voltages for RubberI
8、nsulations) of Test Methods D 470 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 test, insulationresistance, and dc voltage tests in that order when a
9、ny of thesetests are specified. The sequence of other testing is notspecified.5.2 AC Voltage TestUnless otherwise specified, omit thistest if the dc voltage test described in 5.4 is to be performed.Test each insulated conductor for 5 min at the ac withstandvoltage given in Table 1(a) (Conductor Size
10、s, InsulationThicknesses, and AC Test Voltages for Rubber Insulations) ofTest Methods D 470 under the columns labelled “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
11、 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 D 470, con-tains the correction factors. Each insulation manufac
12、turer canfurnish the 1F coefficient for the insulation material by usingthe procedure given in Test Methods D 470. Multiply themeasured value by the correction factor to obtain the insulationresistance value corrected to 60F.5.3.3 If the insulated conductor is covered with a non-metallic sheath so t
13、hat 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.5.4 DC Voltage TestUnless otherwise specified, omit thistest if the ac vol
14、tage test described in 5.2 has been performed.After completion of the insulation resistance test, test each1This 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,
15、 Non-Metallic Shieldings, and Cover-ings for Electrical and Telecommunications Wires and Cables.Current edition approved March 10, 2002. Published June 2002. Originallypublished as D 4245 83. Last previous edition D 4245 97.2Annual Book of ASTM Standards, Vol 10.01.3Annual Book of ASTM Standards, Vo
16、l 10.02.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.insulated conductor for 5 min at the dc test voltage given inTable 1(b) (Conductor Sizes, and DC Test Voltages for RubberInsulations) of Test Methods D 470 under the columns lab
17、eled“Ozone-Resisting Insulations.”6. Cold Bend6.1 The insulation shall not show any cracks when tested ata temperature of 55C in accordance with the procedure andTable number 7 (Mandrel Diameters for Cold Bend Test) inTest Methods D 470.7. Ozone7.1 The insulation shall show no cracking or surface ch
18、eck-ing visible to the unaided eye after exposure to an ozoneconcentration of not less than 0.025 nor more than 0.030 % byvolume, when tested in accordance with Test Methods D 470.8. Heat Distortion8.1 The insulation shall meet the requirements in Table 1when tested in accordance with the procedure
19、in MethodsD 2633.9. Accelerated Water Absorption9.1 The insulated conductor shall meet the requirements inTable 2 when tested in accordance with the procedure in TestMethods D 470. Conduct the electrical method test at 60 Hzwith the water temperature at 75 6 1C.10. Sampling10.1 Unless otherwise inst
20、ructed, sample the insulation inaccordance with Test Methods D 470.11. Test Methods11.1 Unless otherwise instructed, test the insulation inaccordance with Test Methods D 470.12. Keywords12.1 accelerated water absorption; ac voltage test; dc volt-age test; insulation; insulation resistance; 90C dry/7
21、5C wetinsulation; ozone-resistant; thermoplastic elastomer; thermo-plastic elastomer insulationASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determina
22、tion of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or with
23、drawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that you
24、r comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (sing
25、le or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).TABLE 1 Requirements for Physical PropertiesUnaged Requirements:Tensile strength, min,
26、 psi (MPa) 1000 (6.9)Elongation at rupture, min, % 300Aged Requirements:After air-oven test at 121 6 1C for 168 h:Tensile strength and elongation at rupture, min, % ofunaged value75Heat Distortion (At 150 6 1C, max, % of unaged value):4/0 AWG (107 mm2) and smaller (insulation on cable) 50Larger than
27、 4/0 AWG (107 mm2) (buffed sample ofinsulation)50TABLE 2 Accelerated Water Absorption Test RequirementsElectrical Method:Permittivity after 1 day, max 6.0Increase in capacitance, max, %:From 1 to 14 daysFrom 7 to 14 days5.03.0Stability factor after 14 days, max 1.0Alternative, stability factor difference:1 to 14 days, max 0.5D 42452
