1、Designation: D6095 12Standard Test Method forLongitudinal Measurement of Volume Resistivity forExtruded Crosslinked and Thermoplastic SemiconductingConductor and Insulation Shielding Materials1This standard is issued under the fixed designation D6095; the number immediately following the designation
2、 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 test method covers the procedur
3、e for determiningthe volume resistivity, measured longitudinally, of extrudedcrosslinked and thermoplastic semiconducting, conductor andinsulation shields for wire and cable.1.2 In common practice the conductor shield is often re-ferred to as the strand shield.1.3 Technically, this test method is th
4、e measurement of aresistance between two electrodes on a single surface andmodifying that value using dimensions of the specimen geom-etry to calculate a resistivity. However, the geometry of thespecimen is such as to support the assumption of a current pathprimarily throughout the volume of the mat
5、erial between theelectrodes, thus justifying the use of the term “longitudinalvolume resistivity.” (See 3.1.2.1)1.4 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.1.5 This standard does no
6、t 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 health practices and determine the applica-bility of regulatory limitations prior to use. For a specifichazard statement, see 7.1
7、2. Referenced Documents2.1 ASTM Standards:2D257 Test Methods for DC Resistance or Conductance ofInsulating MaterialsD1711 Terminology Relating to Electrical InsulationD4496 Test Method for D-C Resistance or Conductance ofModerately Conductive Materials3. Terminology3.1 Definitions of Terms Specific
8、 to This Standard:3.1.1 semiconducting, adjmoderately conductive, see Ter-minology D1711 and Test Method D4496.3.1.2 longitudinal volume resistivity, nan electrical resis-tance multiplied by a factor calculated from the geometry of aspecimen volume between electrodes in contact with one, andonly one
9、 surface of the specimen.3.1.2.1 DiscussionIn normal wire and cable usage, thelongitudinal volume resistivity is simply referred to as “volumeresistivity.” This usage is at variance with terminology in TestMethods D257, Terminology D1711, and Test Method D4496.4. Significance and Use4.1 The electri
10、cal behavior of semiconducting extrudedshielding materials is important for a variety of reasons, suchas safety, static charges, and current transmission. This testmethod is useful in predicting the behavior of such semicon-ducting compounds. Also see Test Method D4496.5. Apparatus5.1 See Test Metho
11、d D4496 for a description of theapparatus, except the electrode system which is described in7.2.6. Sampling and Test Specimens6.1 Take one 2-ft (600-mm) sample from each lot, or fromeach 25000 ft (7600 m) of completed cable, whichever is less.6.2 The specimen consists of a 10 in. (250 mm) length ofc
12、able core with all layers external to the semi-conductinginsulation shield removed. Use this specimen to test theinsulation shield. To test the conductor shield, bisect thesample longitudinally and remove the conductor. Use only onepiece of the conductor shield as the test specimen.6.3 Condition the
13、 specimens in accordance with TestMethod D4496.6.3.1 If the shielding materials are crosslinked, conditionthe cable core (jacket removed) overnight at 50C to eliminate1This test method is under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and is the direct
14、responsibility ofSubcommittee D09.07 on Electrical Insulating Materials.Current edition approved Nov. 1, 2012. Published November 2012. Originallyapproved in 1997. Last previous edition approved in 2006 as D6095 06. DOI:10.1520/D6095-12.2For referenced ASTM standards, visit the ASTM website, www.ast
15、m.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
16、 C700, West Conshohocken, PA 19428-2959. United States1any acetophenone that is potentially present. Then proceedwith the conditioning in accordance with Test Method D4496.7. Procedure7.1 WarningThoroughly instruct all operators as to thecorrect procedures for performing tests safely.7.2 Apply an el
17、ectrode system consisting of four annularbands of silver paint approximately 0.25 in. (6.5 mm) wide tothe insulation shield. There must be a distance of at least 2 in.(50 mm) of shield between the potential electrodes (the twoinner bands) and a distance of 1 in. of shield between thecurrent electrod
18、es (the outer bands) and the potential elec-trodes. See Annex A1 of Test Method D4496.7.3 For measurement of the conductor shield, bisect thesample longitudinally and remove the conductor. Then, usingonly one piece of the bisected shield, apply the silver paintelectrode system as described in 7.2 on
19、ly to the conductorshield.7.4 Condition the specimen for1hattherated operatingtemperature of the cable to ensure thermal equilibrium of thespecimen.7.5 Determine the resistance between the potential elec-trodes of the test specimen using a direct test voltage and ameasuring system meeting the requir
20、ements of Test MethodD4496. Make two measurements, one at 23 6 2C (73 6 4F)and one at the rated operating temperature of the insulationmaterial. See the procedure and Appendix X1 of Test MethodD4496 concerning the prevention of specimen self-heating.Limiting the power to 100 mW and the test time to
21、1 min isrecommended.7.6 When a high degree of accuracy is not required, use atwo-electrode method employing any technique that permitsthe resistance to be measured with an accuracy of 65 %. Spacethe electrodes at least 2 in. (50 mm) apart. Make two tests, oneat 23 6 2C (73 6 4F) and one at the rated
22、 operatingtemperature of the insulation material.8. Calculation8.1 For each shielding material and each temperature, cal-culate the volume resistivity by using the following equations:Insulation Shielding: 52RDb22 db2! #/L (1)Conductor Shielding: 5 R Da22 da2! #/L (2)where: = volume resistivity, -cm
23、R = measured resistance, ,L = distance between potential electrodes, in.,Da= diameter over conductor shielding, in.,da= diameter over conductor, in.,Db= diameter over insulation shielding, in., anddb= diameter over insulation, in.NOTE 1Even though the dimensions are measured in inches, the valueof
24、the volume resistivity is reported in -cm. This is because not allconstants and conversion factors are shown in Eq 1 and Eq 2. SeeAppendix X1 for a discussion on the derivation of the formulas.9. Report9.1 Report the following information:9.1.1 Sample conditioning time and temperature,9.1.2 The volu
25、me resistivity, -cm, of the conductor shield-ing material at 23 6 2C,9.1.3 The volume resistivity, -cm, of the conductor shield-ing material at the temperature rating of the insulation,9.1.4 The volume resistivity, -cm, of the insulation shield-ing material at 23 6 2C,9.1.5 The volume resistivity, -
26、cm, of the insulation shield-ing material at the temperature rating of the insulation, and9.1.6 The electrode system used.10. Precision and Bias10.1 PrecisionThis test method has been in use for manyyears, but no statement for precision has been made and noactivity is planned to develop such a state
27、ment.10.2 BiasA statement of bias is not possible due to a lackof a standard reference material.11. Keywords11.1 conductor shield; conductor shielding material; insula-tion shield; insulation shielding material; moderately conduc-tive; semiconducting shielding materials; semiconductingshields; volum
28、e resistivity of shielding materialsAPPENDIX(Nonmandatory Information)X1. DERIVATION OF FORMULAS FOR VOLUME RESISTIVITYX1.1 Insulation Shielding Material X1.1 Fig. X1.1 5 R A/L! (X1.1)A 5 D2!/4# 2 d2!/4# 5 D22 d2! #/4 (X1.2) 5 R D22 d2! #/4L (X1.3)where:FIG. X1.1 Insulation ShieldD6095 122 = volume
29、resistivity, -cm,R = measured resistance, ,D = diameter over insulation shielding, in.,d = diameter over insulation, in., andL = distance between potential electrodes, in.X1.1.1 In Eq X1.3, substituting the numerical value for and converting the values in inches to centimetres results in EqX1.4 whic
30、h is the same as Eq 1 in 8.1 which gives the volumeresistivity in the customary units of -cm. 5 2R D22 d2! #/L (X1.4)X1.2 Conductor Shielding Material X1.2 Fig. X1.2 5 RA/L! (X1.5)A 5 $ D2!/4# 2 d2!/4# %/2 5 $ D22 d2# %/8(X1.6) 5 R D22 d2! #/8L (X1.7)where: = volume resistivity, -cm,R = measured res
31、istance, ,D = diameter over conductor shielding, in.,d = diameter over conductor, in., andL = distance between potential electrodes, in.X1.2.1 In Eq X1.7, substituting the numerical value for and converting the values in inches to centimetres results in EqX1.8 which is the same as Eq 2 in 8.1 which
32、gives the volumeresistivity in the customary units of -cm. 5 R D22 d2! #/L (X1.8)SUMMARY OF CHANGESCommittee D09 has identified the location of selected changes to this test method since the last issue,D6095 06, that may impact the use of this test method. (Approved Nov. 1, 2012)(1) Revised section
33、6.3.1.Committee D09 has identified the location of selected changes to this test method since the last issue,D6095 05, that may impact the use of this test method. (Approved April 1, 2006)(1) Revised paragraph 1.5. (2) Revised paragraphs 3.1.2 and 3.1.2.1.ASTM International takes no position respect
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