ASTM_B_193_-_16.pdf

Designation:B19316Standard Test Method forResistivity of Electrical Conductor Materials1This standard is issued under the fixed designation B193;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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This test method covers the determination of the elec-trical resistivity of metallic electrical conductor material.Itprovides for an accuracy of 60.30%on test specimens havinga resistance of 0.00001 (10)or more.Weight resistivityaccuracy may be adversely affected by possible inaccuracies inthe assumed density of the conductor.1.2 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.2.Referenced Documents2.1 ASTM Standards:2A111 Specification for Zinc-Coated(Galvanized)“Iron”Telephone and Telegraph Line WireA326 Specification for Zinc-Coated(Galvanized)High Ten-sile Steel Telephone and Telegraph Line Wire(Withdrawn1990)3B9 Specification for Bronze Trolley WireB105 Specification for Hard-Drawn Copper Alloy Wires forElectric ConductorsB298 Specification for Silver-Coated Soft or Annealed Cop-per WireB355 Specification for Nickel-Coated Soft orAnnealed Cop-per WireB415 Specification for Hard-Drawn Aluminum-Clad SteelWireB498/B498M Specification for Zinc-Coated(Galvanized)Steel Core Wire for Use in Overhead Electrical Conduc-torsB566 Specification for Copper-Clad Aluminum WireB606 Specification for High-Strength Zinc-Coated(Galva-nized)Steel Core Wire for Aluminum and Aluminum-Alloy Conductors,Steel ReinforcedB800 Specification for 8000 Series Aluminum Alloy Wirefor Electrical PurposesAnnealed and Intermediate Tem-persB802 Specification for Zinc-5%Aluminum-MischmetalAlloy-Coated Steel Core Wire for Aluminum Conductors,Steel Reinforced(ACSR)Metric(Discontinued 1998-Replaced by B 802/B802M)B0802_B0802MB803 Specification for High-Strength Zinc5%Aluminum-Mischmetal Alloy-Coated Steel Core Wire for Use inOverhead Electrical ConductorsB957 Specification for Extra-High-Strength and Ultra-High-Strength Zinc-Coated(Galvanized)Steel Core Wire forOverhead Electrical ConductorsB958 Specification for Extra-High-Strength and Ultra-High-Strength Class A Zinc5%Aluminum-Mischmetal Alloy-Coated Steel Core Wire for Use in Overhead ElectricalConductors2.2 NIST Document:NBS Handbook 100 Copper Wire Tables43.Resistivity3.1 Resistivity(Explanatory Note 1)is the electrical resis-tance of a body of unit length,and unit cross-sectional area orunit weight.3.2 Volume Resistivity is commonly expressed in ohms for atheoretical conductor of unit length and cross-sectional area;ininch-pound units in cmil/ft and in acceptable metric units in mm2/m.It may be calculated by the following equation:v5A/L!Rwhere:v=volume resistivity,cmil/ft or mm2/m,A=cross-sectional area,cmil or mm2,1This test method is under the jurisdiction of ASTM Committee B01 onElectrical Conductors and is the direct responsibility of Subcommittee B01.02 onMethods of Test and Sampling Procedure.Current edition approved April 1,2016.Published April 2016.Originallyapproved in 1944.Last previous edition approved in 2014 as B193 02(2014).DOI:10.1520/B0193-16.2For 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.4Available from National Institute of Standards and Technology(NIST),100Bureau Dr.,Stop 1070,Gaithersburg,MD 20899-1070,http:/www.nist.gov.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 L=gage length,used to determine R,ft or m,andR=measured resistance,.3.3 Weight Resistivity is commonly expressed in ohms for atheoretical conductor of unit length and weight.The methodfor calculating weight resistivity,based on resistance,length,and weight measurements,of a test specimen is given inExplanatory Note 2.4.Apparatus4.1 Resistance shall be measured with a circuit configura-tion and instrumentation that has a resistance measurementcapability of 60.15%accuracy.5.Test Specimen5.1 The test specimen may be in the form of a wire,strip,rod,bar,tube,or shape.It shall be of uniform cross sectionthroughout its length within 60.75%of the cross-sectionalarea.Wherever possible it shall be the full cross section of thematerial it represents,if the full cross section is such that theuniformity of the cross-sectional area can be ac