ASTM_D_6095_-_12.pdf

Designation:D609512Standard 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 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 procedure 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 the 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 material 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 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 health practices and determine the applica-bility of regulatory limitations prior to use.For a specifichazard statement,see 7.1.2.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 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,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 electrical 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 Method 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 ofcable 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 specimens in accordance with TestMethod D4496.1This test method is under the jurisdiction of ASTM CommitteeD09 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.1,2012.Published November 2012.Originallyapproved in 1997.Last previous edition approved in 2006 as D609506.DOI:10.1520/D6095-12.2For 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 6.3.1 If the shielding materials are crosslinked,conditionthe cable core(jacket removed)overnight at 50C to eliminateany 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 electrode 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 el