Designation:B778−19StandardSpecificationforShapedWireCompactConcentric-Lay-StrandedAluminumConductors(AAC/TW)1ThisstandardisissuedunderthefixeddesignationB778;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thisspecificationcoversshapedwirecompactconcentric-lay-strandedaluminumconductor(AAC/TW)anditscomponentwiresforuseasoverheadelectricalconductors(ExplanatoryNote1andNote2).1.2Thevaluesstatedininch-poundunitsaretoberegardedasthestandardwiththeexceptionoftemperatureandresistiv-ity.TheSIequivalentsofinch-poundunitsmaybeapproxi-mate.NOTE1—AAC/TWisdesignedtoincreasethealuminumareaforagivendiameterofconductorbytheuseoftrapezoidallyshapedwires(TW).Theconductorsconsistofacentralcoreofoneroundaluminumwireoraseven-strandcompactroundcoresurroundedbytwoormorelayersoftrapezoidalaluminum1350-H19wires.Forthepurposesofthisspecification,thesizeslistedaretabulatedonthebasisofthefinishedconductorhavinganareaequaltothatofspecificsizesofstandardAAC(Table1)orinfixeddiameterincrements(Table2)soastofacilitateconductorselection.NOTE2—ThealuminumandtemperdesignationsconformtoANSIStandardH35.1.Aluminum1350correspondstoUnifiedNumberingSystem(UNS)A91350inaccordancewithPracticeE527.1.3Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1Thefollowingdocumentsoftheissueineffectondateofmaterialpurchaseformapartofthisspecificationtotheextentreferencedherein.2.2ASTMStandards:2B230/B230MSpecificationforAluminum1350–H19WireforElectricalPurposesB263TestMethodforDeterminationofCross-SectionalAreaofStrandedConductorsB354TerminologyRe...
