ASTM_D_4872_-_14.pdf

Designation:D487214Standard Test Method forDielectric Testing of Wire and Cable Filling Compounds1This standard is issued under the fixed designation D4872;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 determination of dissipationfactor,permittivity(dielectric constant),and ac volume resis-tivity of wire and cable filling compounds and related materialsthat are solid at room temperature,but capable of being meltedat elevated temperature.1.2 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.1.3 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.Specific hazardstatements are given in Section 7.2.Referenced Documents2.1 ASTM Standards:2D150 Test Methods for AC Loss Characteristics and Permit-tivity(Dielectric Constant)of Solid Electrical InsulationD257 Test Methods for DC Resistance or Conductance ofInsulating MaterialsD1321 Test Method for Needle Penetration of PetroleumWaxesD1711 Terminology Relating to Electrical InsulationD6054 Practice for Conditioning Electrical Insulating Mate-rials for Testing(Withdrawn 2012)33.Terminology3.1 DefinitionsFor definitions of terms used in this testmethod,refer to Terminology D1711.4.Summary of Test Method4.1 Place a measured volume of melted sample,free ofentrapped air,into a level preheated specimen dish.Allow thespecimen to cool and place primary and secondary electrodesin uniform contact with the specimen surface.Connect testleads to the specimen dish and the cover plate electrode;makemeasurements to obtain values from which dissipation factor,permittivity,and dc volume resistivity are calculated.5.Significance and Use5.1 Dissipation factor,permittivity,and dc volume resistiv-ity are properties of communication cable fillers and fillercomponents that are controlled in order that the cableselectrical performance falls within its design limits.Relativelysmall amounts of contaminants,such as polar compounds,water,or salts degrade the cables electrical properties.Limitson the dielectric properties of the cable filling compound areusually specified by the cable manufacturer,by industrystandards or both.6.Apparatus6.1 Specimen Dish and Cover Electrode,as shown in Fig.1.Use a gold-or nickel-plated specimen dish and cover electrodeplate to ensure a corrosion resistant,high conductivity surface.6.1.1 Clean the specimen dish and electrode plate of oxida-tion by rinsing in a 5%hydrochloric acid solution for amaximum of 5 s,followed by distilled water,isopropyl alcoholand,finally,by a low boiling petroleum distillate(naphtha)(seeSection 7).Alternatively(preferred),use an ultrasonic cleans-ing bath.Store the dish and cover,wrapped in paper towels,ina desiccator or in an oven maintained at 50C.6.2 Dial Comparator,having a minimum travel of 0.4 in.(10.2 mm)or equivalent.6.3 Leveling Table,adjustable to 61 min of arc.The basefrom a Test Method D1321 penetrometer is satisfactory.6.4 Glass Syringe,10.0-mL capacity.6.5 Oven,capable of maintaining the temperature used todetermine viscosity for the particular compound under test.6.6 Q-Meter,or equivalent.6.7 Teraohm Meter,or equivalent.1This test method 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.1,2014.Published November 2014.Originallyapproved in 1988.Last previous edition approved in 2010 as D4872 99(2010).DOI:10.1520/D4872-14.2For 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.3The last approved version of this historical standard is referenced onwww.astm.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 States1 7.Hazards7.1 The chemicals used in cleaning the sample dish areconsidered hazardous.Exercise care in handling hydrochloricacid and naphtha.Naphtha is extremely flammable;do not usein an area near sparks or open flame.8.Sample and Test Specimen8.1 The sample is to be representative of the material to betested.Approximately 100 g of material is sufficient for severalspecimens.9.Ca