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11KV/415VOverheadLineSpecification(REC)

JUNE8,2011 101COMMENTS(HTTPS://ELECTRICALNOTES.WORDPRESS.COM/2011/06/08/11KV415VOVERHEADLINESPECIFICATIONREC/#COMMENTS)

11KV/415VoverHeadLinesSpecificationandInstallation(REC):

11KVLIGHTNINGARRESTER(IS:3070(PtII)).

VoltageRatingforLA:

Theratedvoltageoflightningarrestersshallbe9KV(rms).Thiswillbeapplicabletotheeffectivelyearthed11KVsystemscoefficientofearthnotexceeding80percentasperIS:4004withallthetransformerneutralsdirectlyearthed.

NormalDischargeCurrentRatingforLA:

Thenominaldischargecurrentratingofthelightningarrestersshallbe5KA.

TestsforLA:

ThefollowingroutineandtypetestsaslaiddowninIS:3070(PartI)shallbecarriedout.RoutineTest:DryPowerfrequencysparkovertest.TypeTests(Confirmation):

1. Voltagewithstandtestsofarresterinsulation.2. Powerfrequencysparkovertest3. Hundredpercent1.2/550microsecondimpulsesparkovertest4. Frontofwaveimpulsesparkovertest.5. Residualvoltagetest.6. Impulsecurrentwithstandtest.7. Operatingdutytest.8. Temperaturecycletestonporcelainhousing.9. Porositytestonporcelaincomponents.

10. Galvanizingtestonmetalparts.

11KVDROPOUTFUSECUTOUTS:(IS:9385(partItoIII).)

Thedistributionfusecutoutsshallbeoutdoor,open,dropoutexpulsiontypefusecutoutssuitableforinstallationin50Hz,11KVdistributionsystem.Theratedvoltageshallbe12KV.Theratedcurrentshallbe100A.

RatedLightingImpulsewithstandsVoltageforFuse:

Toearthandbetweenpoles75KV(Peak)Acrosstheisolatingdistanceoffusebase86KV(Peak)

RatedOneMinutePowerFrequencyWithstandVoltage(Wet&Dry)forFuse:

Toearthandbetweenpoles28KV(rms)Acrosstheisolatingdistance32KV(rms)

TemperatureRiseLimitforFuse:

Coppercontactssilverfaced650CTerminals500CMetalpartsactingasspringThetemperatureshallnotreachsuchavaluethatElasticityofthemetalischanged

RatedBreakingCapacityforFuse:

Theratedbreakingcapacityshallbe8KA(Asymmetrical).

ConstructionDetailsforFuse:

Thecutoutsshallbeofsingleventtype(downward)havingafrontconnectedfusecarriersuitableforanglemounting.AllferrouspartsshallbehotdipgalvanizedinaccordancewiththelatestversionofIS:2632.NutsandboltsshallconformtoIS:1364.Springwashersshallbeelectrogalvanized.

FuseBaseTopAssembly:

Thetopcurrentcarryingpartsshallbemadeofahighlyconductivecopperalloyandthecontactportionshallbesilverplatedforcorrosionresistanceandefficientcurrentflow.Thecontactshallhaveasocketcavityforlatchingandholdingfirmlythefusecarrieruntilthefaultinterruptioniscompletedwithinthefuse.Thetopassemblyshallhaveanaluminumalloyterminalconnector.Thetopassemblyshallberobustenoughtoabsorbbulkoftheforcesduringthefusecarrierclosingandopeningoperationsandshallnotoverstressthespringcontact.Itshallalsoprohibitaccidentalopeningofthefusecarrierduetovibrationsorimpact.

FuseBaseBottomAssembly:

Theconductingpartsshallbemadeofhighstrengthhighlyconductivecopperalloyandthecontactportionshallbesilverplatedforcorrosionresistanceandshallprovidealowresistancecurrentpathfromthebottomfusecarriercontactstothebottomterminalconnector.

FuseCarrierTopAssembly:

Thefusecarriertopcontactshallhaveasolidreplaceablecapmadefromhighlyconductive,anticorrosivecopperalloyandthecontactportionshallbesilverplatedtoprovidealowresistancecurrentpathfromtheFuseBaseTopContacttotheFuseLink.Itshallmakeafirmcontactwiththebuttonheadofthefuselinkandshallprovideaprotectiveenclosuretothefuselinktocheckspreadingofarcduringfaultinterruptions.Thefusecarriershallbeprovidedwithacastbronzeopeningeye(pullring)suitableforoperationwithahookstickfromthegroundleveltopulloutorcloseinthefusecarrierbymanualoperation.

FuseCarrierBottomAssembly:

Thefusecarrierbottomassemblyshallbemadeofbronzecastingswithsilverplatingatthecontactpointstoefficientlytransfercurrenttofusebase.Itshallmakesmoothcontactwiththefusebasebottomassemblyduringclosingoperation.Thebottomassemblyshallhavealiftingeyeforthehookstickforremovingorreplacingthefusecarrier.

FuseBase(Porcelain):

Thefusebaseshallbeabirdproof,singleunitporcelaininsulatorwithacreepagedistance(toearth)notlessthan320mm.Thetopandbottomassembliesasalsothemiddleclampinghardwareshallbeeitherembeddedintheporcelaininsulatorwithsulphurcementorsuitablyclampedinposition.Forembeddedcomponents,thepulloutstrengthshouldbesuchastoresultinbreakingoftheporcelainbeforepulloutoccursinatest.Forporcelaininsulators,thebeamstrengthshallnotbelessthan1000kg.

FuseTube:

Thefusetubeshallbemadeoffiberglasscoatedwithultravioletinhibitorontheoutersurfaceandhavingarcquenchingbonefirelinerinside.Thetubeshallhavehighburstingstrengthtosustainhighpressureofthegasesduringfaultinterruption.Theinsidediameterofthefusetubeshallbe17.5mm.Thesolidcapofthefusecarriershallclampthebuttonheadofthefuselink,closingthetopendofthefuseandallowingonlythedownwardventingduringfaultinterruption.

TypeTests(IS:9385PartI&II)forFuse:

DielectrictestsTemperaturerisetest

MountingArrangementforFuse:

Thecutoutsshallbeprovidedwithasuitablearrangementformountingtheseon74X40mmor100X50mmchannelcrossarminsuchawaythatthecenterlineofthebaseisatanangleof15to20degfromtheverticalandshallprovidethenecessaryclearancesfromthesupport.Mountingarrangementshallbemadeofhighstrengthgalvanizedsteelflatandshallberobustenoughtosustainthevariousstressesencounteredduringalloperatingconditionsofthecutout.

11KVPORCELAININSULATORS:(IS:731andIS:3188):

Theporcelainshallbesound,freeformdefects,throughverifiedandsmoothlyglazed.Unlessotherwisespecified,theglazeshallbebrowncolor.Theglazeshallcoveralltheporcelainpartsofinsulatorsexceptthoseareaswhichserveassupportduringfiringareleftunglazedforthepurposeofassembly.Thedesignofinsulatorsshallbesuchthatstressesduetoexpansionandcontractioninanypartoftheinsulatorshallnotleadtodeterioration.Theporcelainshallnotengagedirectlywithhardmetal.Cementusedinconstructionofinsulatorsshallnotcausefracturebyexpansionorlooseningbycontractionandpropercareshallbetakentolocatetheindividualpartscorrectlyduringcementing.Thecementshallnotgiverisetochemicalreactionwithmetalfittingsanditsthicknessshallbeasuniformaspossible.Theinsulatorsshouldpreferablybemanufacturedinautomatictemperaturecontrolledkilnstoobtainuniformbakingforbetterelectricalandmechanicalproperties.BothpinandstraininsulatorsshallconformtoTypeBofIS:731.ThestraininsulatorsshallbeofTongueandClevistype.

TestVoltageforInsulator:

HighestSystemVoltage:12KV(rms)VisibleDischargeTest:9KV(rms)WetPowerFrequencyWithstandTest35KV(rms)PowerFrequencyPunctureWithstandTest(PinInsulator):105KV(rms)PowerFrequencyPunctureWithstandTest(StrainInsulator):1.3timestheactualdryflashovervoltageoftheinsulator.ImpulseVoltageWithstandTest:75KV(rms)

FailingLoadforInsulator:

MechanicalFailingLoad(ForPinInsulatorsonly):Theinsulatorsshallbesuitableforaminimumfailingloadof10KNappliedintransversedirector.ElectroMechanicalFailingLoad(ForStrainInsulators):Theinsulatorsshallbesuitableforaminimumfailingloadof70KNappliedaxially.

CreepageDistanceforInsulator:

HighestSystemVoltage:12KVHeavilyPollutedAtmospherePinInsulator:320mmHeavilyPollutedAtmosphereStrainInsulator:400mm

Tests:(AsperIS:731)forInsulator.

1. Visualexamination2. Verificationofdimensions

3. Visibledischargetest4. ImpulseVoltagewithstandTest5. WetPowerFrequencyVoltagewithstandTest6. TemperatureCycleTest7. MechanicalFailingLoadTest8. 24hourMechanicalStrengthTestforStrainInsulators9. PunctureTest

10. PorosityTest11. GalvanizingTest12. ElectroMechanicalFailingLoadTest

RoutineTestsforInsulator

1. Virtualexamination2. Mechanicalroutinetest3. Electricalroutinetest

AcceptanceTestforInsulator

1. VerificationofDimensions2. TemperatureCycleTest3. ElectroMechanicalFailingLoadTest4. PunctureTest5. PorosityTest6. GalvanizingTest

MarkingforInsulator:

NameortrademarkofmanufacturerMonthandyearofmanufactureMinimumfailingloadinKNISIcertificatemark,ifanyMarkingsonporcelainshallbeprintedandshallbesuppliedbeforefiring.

PinInsulators:

Thepinsshallofsinglepieceobtainedpreferablybytheprocessofforging.Theyshallnotbemadebyjoining,welding,shrinkfittingoranyotherprocessusingmorethanonepiecematerial.Thepinsshallbeofgoodfinish,freefromflawsandotherdefects.Thefinishofthecollarshallbesuchthatsharpanglebetweenthecollarandtheshankisavoided.Aluminumferrouspins,nutsandwashers,exceptthosemadeofstainlesssteel,shallbegalvanized.Thethreadsofnutsandtapedholewhencutaftergalvanizingshallbewelloiledorgreased.

DimensionsforPinInsulators:

PinsshallbeofsmallsteelheadtypeS165PasperIS:2486(PartII)havingstalklengthof165mmandshanklengthof150mmwithminimumfailingloadof10KN.

Tests:(IS:2486(PartI))forPinInsulators

CheckingofthreadsonheadsGalvanizingtestVisualexaminationtestMechanicaltestGalvanizingtestMechanicaltestVisualexaminationtest

HelicallyFormedPinInsulatorTies:

HelicallyformedtiesusedforholdingtheconductoronthepininsulatorshallbemadeofaluminumalloyoraluminizedsteeloraluminumcladsteelwiresandshallconformtotherequirementsofIS:12048.ThetiesshallbesuitableforpininsulatordimensionsofPt.Iandconductorsizesspecified.Elastomerpadforinsulatorshallbeusedwiththetiestoavoidabrasionoftheconductorcomingintodirectcontactwiththeinsulator.

CrossarmstrapconformingtoIS:2486(Pt.II).

Aluminumalloydiecastthimbleclevisforattachingtothetongueofstrain,insulatorononeendandforaccommodatingtheloopofthehelicallyformeddeadendfittingattheotherendinitssmoothinternalcontour.ThethimbleshallbesuitableforallsizesofACSRconductorsasspecified.Thethimbleclevisshallbeattachedtotheinsulatorbyasteelcuttingpinusedwithanonferroussplitpinofbrassorstainlesssteel.ThethimbleshallhaveclevisdimensionsasperIS:2486(PtII).Helicallyformeddeadendgriphavingaprefabricatedlooptofitintothegroovedcontourofthethimbleononeendandforapplicationovertheconductorattheotherend.TheformedfittingshallconformtotherequirementofIS:12048.

FittingsforstrainInsulatorsofBall&SocketType:

CrossarmstrapconformingtoIS:2486(PtII).Forgedsteelballeyeforattachingthesocketendofthestraininsulatortothecrossarmstrap.ForgingsshallbemadeofsteelasperIS:2004.Aluminumalloythimblesocketmadeoutofpermanentmouldcast,highstrengthaluminumalloyforattachingtothestraininsulatorononeendandforaccommodatingtheloopofthehelicallyformeddeadendfittingsattheotherendinitssmoothinternalcontour.ThethimblesocketshallbeattachedtothestraininsulatorwiththehelpoflockingpinasperthedimensionsgiveninIS:2486(PtII).

Tests

ThehelicallyformedfittingsforstraininsulatorsshallbesubjectedtotestsasperIS:12048.TheotherhardwarefittingsshallbetestedasperIS:2486(PartI).

FittingsforstrainInsulatorswithHelicallyFormedConductorsDeadEndGrips:

FittingsforStrainInsulatorsofTongue&ClevisType

Thefittingsshallconsistofthefollowingcomponents:

1. CrossarmstrapconformingtoIS:2486(Pt.II)1989.2. Aluminumalloydiecastthimbleclevisforattachingtothetongueofstraininsulatorononeendandforaccommodatingthe

loopofthehelicallyformeddeadendfittingattheotherendinitssmoothinternalcontour.Thethimbleshallbesuitableforallsizesofconductorsrangingfrom7/2.11mmto7/3.35mmACSR.Thethimbleclevisshallbeattachedtotheinsulatorbyasteelcutterpinusedwithanonferroussplitpinofbrassorstainlesssteel.ThethimbleshallhaveclevisdimensionsasperIS:2486(Pt.II)1989.

3. Helicallyformeddeadendgriphavingaprefabricatedlooptofitintothegroovedcontourofthethimbleononeendandforapplicationovertheconductorattheotherend.TheformedfittingshallconformtotherequirementofIS:120481987.

Note:Asthehelicallyformedfittingsaremadetosuitspecificsizesofconductors,thepurchaseshouldclearlyspecifythenumberoffittingsrequiredforeachsizeofconductor

FittingsforstrainInsulatorswithConventionalDeadendClampsAlternativetoFittingCovered:

Fittingsforstraininsulatorswithconventionaldeadendclampsforusewithtongue&clevisorball&sockettypeinsulatorsshallconsistofthefollowingcomponents:

1. CrossarmsstrapconformingtoIS:2486(Pt.II)19892. DeadendclampmadeofaluminumalloytosuitACSRconductorsfrom7/2.11mmto7/3.35mm.Theultimatestrengthofthe

clampshallnotbelessthan3000Kg.TheshapeandmajordimensionsofclampssuitableforB&SandT&Cinsulatorsareshowninfigures7&8respectively.

GUYSTRAININSULATORS:(IS:5300)

Theporcelaininsulatorshallbesound,freefromdefects,thoroughlyverifiedandsmoothlyglazed.Thedesignoftheinsulatorshallbesuchthatthestressestoexpansionandcontractioninanypartoftheinsulatorshallnotleadtoitsdeterioration.Theglaze,unlessotherwisespecified,shallbebrownincolor.Theglazeshallcovertheentireporcelainsurfacepartsexceptthoseareasthatserveassupportsduringfiring.

TypeforGuyInsulators:

ThestandardguystraininsulatorsshallbedesignationsAandCasperIS:5300.Therecommendedtypeofguystraininsulatorsforuseonguywiresofoverheadlinesofdifferentvoltagelevelsareasfollows:PowerLineVoltage:11KVDesignationofInsulators:CDryoneminutePowerFrequencywithstandVoltage:27KV(rms)WetoneminutePowerFrequencywithstandVoltage:13KV(rms)MinimumFailingLoad:88(KN)

Tests:(IS:5300)forGuyInsulators.

1. Visualexamination2. Verificationofdimensions

3. Temperaturecycletest4. Dryoneminutepowerfrequencyvoltagewithstandtest5. Wetoneminutepowerfrequencyvoltagewithstandtest6. Mechanicalstrengthtest7. Porositytest8. AcceptanceTests:(tobeconductedinthefollowingorder)9. Verificationofdimensions

10. Temperaturecycletest11. Mechanicalstrengthtest12. Porositytest

MarkingforGuyInsulators:

Nameortrademarkofthemanufacturer.Yearofmanufacture.ISIcertificatemark,ifanyMarkingonporcelainshallbeappliedbeforefiring.

TypeofInsulatorsforGuyInsulators:

ThestandardguystraininsulatorsshallbeofdesignationsAandCasperIS:5300.Therecommendedtypeofguystraininsulatorsforuseonguywiresofoverheadlinesofdifferentvoltagelevelsareasfollows:

LineVoltage DesignationofInsulator

415/240Volt AType

11KV CType

33KV CType(2NosofStringsinSeries).

BasicInsulatorLevelforGuyInsulators:

DesignationofInsulator

Dryoneminpowerfrequencywithstand

Wetoneminpowerfrequencywithstand

AType 18KV(rms) 8KV(rms)

CType 27KV(rms) 13KV(rms)

MechanicalStrengthforGuyInsulators:

Theinsulatorsshallbesuitablefortheminimumfailingloadsspecifiedasunder:

DesignationofInsulator MinimumFailingLoad

AType 44KN

CType 88KN

RoutineTestasperTests(IS:5300)forGuyInsulators:

1. Visualexamination2. Verificationofdimensions3. Temperaturecycletest4. Dryoneminutepowerfrequencyvoltagewithstandtest5. Wetoneminutepowerfrequencyvoltagewithstandtest6. Mechanicalstrengthtest7. Porositytest

AcceptanceTests(tobeconductedinthefollowingorder):

1. Verificationofdimensions2. Temperaturecycletest3. Mechanicalstrengthtest4. Porositytest

DANGERNOTICEPLATES:

AsperprovisionsofIERules1956,DangerNoticePlatesinHindiorEnglishand,inaddition,inthelocallanguagewiththesignofskullandbonesarerequiredtobeprovidedonpowerlinesupportsandotherinstallations.ItisfurtherstipulatedintheI.E.RulesthatsuchNoticePlatesarenotrequiredtobeprovidedonsupportslikePCC,tubular,wood,steelrails,etc.whichcannotbeclimbedeasilywithouttheaidofladderorspecialappliances.Toadoptauniformpatternandforhelpingeasyprocurement,aspecificationonDangerNoticePlateshasbeendrawnup.

StandardsofDangerPlate

TheDangerNoticePlatesshallcomplywithIS:25511982.

DimensionsofDangerPlate

TwosizesofDangerNoticePlatesasfollowsarerecommended:

1. Fordisplayat415Vinstallations200x150mm2. Fordisplayat11KV(orhighervoltages)installations250x200mm

Thecornersoftheplateshallberoundedoff.ThelocationoffixingholesasshowninFigs.1to4isprovisionalandcanbemodifiedtosuittherequirementsofthepurchaser.

LetteringofDangerPlate

Allletteringsshallbecentrallyspaced.Thedimensionsoftheletters,figuresandtheirrespectivepositionshallbeasshowninfigs.Thesizeoflettersinthewordsineachlanguageandspacingbetweenthemshallbesochosenthattheseareuniformlywritteninthespaceearmarkedforthem.

LanguagesofDangerPlate

UnderRuleNo.35ofIndianElectricityRules,1956,theownerofeverymedium,highandextrahighvoltageinstallationis

requiredtoaffixpermanentlyinaconspicuouspositionadangernoticeinHindiorEnglishand,inaddition,inthelocallanguage,withthesignofskullandbones.ThetypeandsizeofletteringtobedoneinHindiisindicatedinthespecimendangernoticeplatesshowninFig.2and4andthoseinEnglishareshowninFigs.AdequatespacehasbeenprovidedinthespecimendangernoticeplatesforhavingtheletteringsinlocallanguagefortheequivalentofDanger,41511000andVolts.

Material&FinishingofDangerPlate:

Theplateshallbemadefrommildsteelsheetofatleast1.6mmthickandvitreousenameledwhite,withletters,figuresandtheconventionalskullandcrossbonesinsignalredcolor(referIS:51978)onthefrontside.Therearsideoftheplateshallalsobeenameled.

TestsofDangerPlate:

Thefollowingtestsshallbecarriedout:

1. VisualexaminationasperIS:255119822. DimensionalcheckasperIS:255119823. TestforweatherproofnessasperIS:87091977(oritslatestversion)

ACSRandAACoverheadconductors:

AConferenceonStandardizationofSpecificationsandConstructionPracticesinRuralElectrificationwasheldon4thand5thJanuary,1971inNewDelhi.BesidestheRuralElectrificationCorporation,representativesofvariousStateElectricityBoards,theIndianStandardsInstitution(BIS),CentralWater&PowerCommission(CEA),CentralBoardofIrrigationandPowerandmanyotherorganizationsparticipatedinthediscussions.BasedontheconsensusarrivedattheConference,RECSpecificationNo.1/1971covering7/2.21mm(25mm2aluminumarea)and7/3.10mm(50mm2aluminumarea)AACforuseonLTlinesand7/2.59mm(30mm2aluminumarea)and7/3.35mm(50mm2aluminumarea)ACSRforuseon11KVandLTlineswasissued.Subsequently,theSpecificationwasrevisedtoincorporateanadditionalsizeofACSRviz7/2.11mm(20mm2aluminumarea)foruseon11KVandLTlinesandthenagaintoincorporatethreemoresizesofACSRviz.7/3.35mm(50mm2aluminumarea),7/4.09mm(80mm2aluminumarea)and6/4.72mm+7/1.57mm(100mm2aluminumarea)foruseon33KVlines.Thesizesofconductorsstandardizedforlinesofdifferentvoltagesareindicatedbelow:

ACSRConductorfor33KVLines:

1. ACSR7/3.35mm(50mm2aluminumarea)2. ACSR7/4.09mm(80mm2aluminumarea)3. ACSR6/4.72mm+7/1.57mm(100mm2aluminumarea)

ACSRConductorfor11KVLines

1. ACSR7/2.11mm(20mm2aluminumarea)2. ACSR7/2.59mm(30mm2aluminumarea)3. ACSR7/3.35mm(50mm2aluminumarea)

ACSRConductorforLTLines

1. ACSR7/2.11mm(20mm2aluminumarea)2. ACSR7/2.59mm(30mm2aluminumarea)3. ACSR7/3.35mm(50mm2aluminumarea)4. AAC7/2.21mm(25mm2aluminumarea)5. AAC7/3.10mm(50mm2aluminumsarea)

StandardsforACSRConductor:

IS:398(Pt.I)1976andIS:398(Pt.II)1976.

JointinWires&Conductors:

Allaluminumsconductors:Nojointsshallbepermittedinanywire.AluminumConductorSteelReinforced:

AluminumWiresforACSRConductor:

Notwojointsshalloccurinthealuminumswiresclosertogetherthan15meters.

SteelWiresforACSRConductor:

NojointsshallbepermittedinsteelwiresusedforACSRofSizes20mm2aluminumsarea(7/2.11mm),30mm2aluminumsarea(7/2.59mm),50mm2aluminumsarea(7/3.35mm)and80mm2aluminumsarea(7/4.09mm).InthecaseofACSRof100mm2aluminumsarea(6/4.72mm+7/1.57mm)havingsevengalvanizedsteelwires,joints,inindividualwiresshallbepermittedbutnotwosuchjointsshallbelessthan15metersapartinthecompletesteelcore.

TestsforACSRConductor:

Thesamplesofindividualwiresforthetestsshallnormallybetakenbeforestranding.Themanufacturershallcarryouttestonsamplestakenoutatleastfrom10%ofaluminumswirespoolsand10%ofsteelwirecoils.However,whendesiredbythepurchaser,thetestsamplemaybetakenfromthestrandedwires.ThewiresusedforallaluminumsconductorsshallcomplywiththefollowingtestsasperIS:398(Pt.I)1976.

1. Breakingloadtest2. Wrappingtest3. Resistancetest

Thewiresusedforaluminumsconductors,steelreinforcedshallcomplywiththefollowingtestsasperIS:398

1. Breakingloadtest2. Ductilitytest3. Wrappingtest4. Resistancetest5. Galvanizingtest

Packing&Marking:(IS:17781980)

Thegrossmassforvariousconductorsshallnotexceedbymorethan10%ofthevaluesgiveninthefollowing

ConductorSizeGrossMassforACSRConductor

(1)AAC

25mm2Al.area(7/2.21mm)500Kg.50mm2Al.area(7/3.10mm)500Kg.

(2)ACSR

20mm2Al.area(7/2.11mm)1000Kg.30mm2Al.area(7/2.59mm)1000Kg.50mm2Al.area(7/3.35mm)1500Kg.80mm2Al.area(7/4.09mm)1500Kg.100mm2Al.area(6/4.72mm+7/1.57mm)2000Kg.

ConductorSizeNormalconductorlengthforACSRConductor

1. AAC

25mm2Al.area(7/2.21mm)1.0Km.50mm2Al.area(7/3.10mm)1.0Km.

1.ACSR

20mm2Al.area(7/2.11mm)2.0Km.30mm2Al.area(7/2.59mm)2.0Km.50mm2Al.area(7/3.35mm)2.0Km.80mm2Al.area(7/4.09mm)1.5Km.100mm2Al.area(6/4.72mm+7/1.57mm)2.0Km.Longerlengthsshallbeacceptable.Shortlengths,notlessthan50%ofthestandardlengths,shallbeacceptabletothemaximumextentof10%ofthequantityordered.

MarkingforACSRConductor:

Thefollowinginformationshallbemarkedoneachpackage:

1. Manufacturersname2. Trademark,ifany3. Drumoridentificationnumber4. Sizeofconductor5. Numberandlengthsofconductor6. Grossmassofthepackage7. Netmassofconductor8. I.S.Icertificationmark,ifany

PrestressedCementConcretePoles(FOS2.5)For11KV&LTLines:

Aresearchprojectforevolvingeconomicaldesignsofcementconcretepolesforuseon11KVandLTLineswasentrustedtotheCementResearchInstitute(CRI)ofIndia.ThebasicdesignparametersforthesepolesasgiveninClause6ofthisSpecificationwereapprovedbytheFifthConferenceonstandardizationofSpecificationsandConstructionPracticesinRuralElectrificationheldinMay,1974.Someofthesedesignparameterswhichwerebasedoncertainforeigncodes/practicesandcertainotherprovisionsofthisSpecification,althoughatvariancewiththestipulationsofIS:16781960,hadbeenadoptedtoachieveeconomyinthedesigns.However,thesemodificationshavesincebeenincorporatedintherevisedIS:16781978.ThisSpecificationcoversPCCpoleswithanoveralllengthof7.5M,8.0Mand9.0Msuitableforuseinoverhead11KVandL.T.powerlinesanddoublepolestructuresfor11/0.4KVsubstations.

ApplicationStandardforPCCPole:

IS:16781978,Specificationforprestressedconcretepolesforoverheadpower,tractionandtelecommunicationlines.IS:29051966.Methodsoftestforconcretepolesforoverheadpowerandtelecommunicationlines.IS:73211974.Codeofpracticeforselection,handlinganderectionofconcretepolesforoverheadpowerandtelecommunicationlines.

AveragePermanentLoadforPCCPole:

Thatfractionoftheworkingloadwhichmaybeconsideredoflongdurationoveraperiodofoneyear.

LoadFactorforPCCPole:

Theratioofultimatetransverseloadtothetransverseloadatfirstcrack.

TransverseforPCCPole:

Thedirectionofthelinebisectingtheanglecontainedbytheconductoratthepole.Inthecaseofastraightrun,thiswillbenormaltotherunoftheline.

TransverseLoadatFirstCrackforPCCPole:

Fordesign,thetransverseloadatfirstcrackshallbetakenasnotlessthanthevalueoftheworkingload.

WorkingloadforPCCPole:

Themaximumloadinthetransversedirection,thatiseverlikelytooccur,includingthewindpressureonthepole.Thisloadisassumedtoactatapoint600mmbelowthetopwiththebuttendofthepoleplantedtotherequireddepthasintendedinthedesign.

UltimateFailureforPCCPole:

Theconditionsexistingwhenthepoleceasestosustainaloadincrementowingtoeithercrushingofconcrete,orsnappingoftheprestressingtendonorpermanentstretchingofthesteelinanypartofthepole.

UltimateTransverseLoadforPCCPole:

Theloadatwhichfailureoccurs,whenitisappliedatapoint600mmbelowthetopandperpendiculartotheaxisofthepolealongthetransversedirectionwiththebuttendofthepoleplantedtotherequireddepthasintendedinthedesign.

ApplicationforPCCPole:

7.5Mand8.0MPoles

Thesepolesshallbeusedattangentlocationsfor11KVandL.T.linesinwindpressurezonesof50kg/M2,75Kg/M2and100Kg/M2inaccordancewithRECConstructionStandardsreferredtointhefollowing:

Polelength:7.5M

11KVlineswithoutearthwireL.T.lines,horizontalformation.ReferencetoRECConstructionStandards:A4,B5

Polelength:8M

11KVlineswithearthwireL.T.lines,verticalformation.ReferencetoRECConstructionStandards:A5,B6

9.0MPoles

ThesepolesshallbeusedfordoublepolestructuresofdistributiontransformercentersasperRECConstructionStandardsF1toF4andforspeciallocationsin11KVandL.T.Lines,suchasroadcrossingsetc.

MaterialsforPCCPole::

(1)Cement

ThecementusedinthemanufactureofprestressedconcretepolesshallbeordinaryorrapidhardeningportlandcementconformingtoIS:2691976(Specificationforordinaryandlowheatportlandcement)orIS:8041E1978(Specificationforrapidhardeningportlandcement).

(2)Aggregates

AggregatesusedforthemanufactureofprestressedconcretepolesshallconformtoIS:3831970(Specificationforcoarseandfineaggregatesfromnaturalsourcesforconcrete).Thenominalmaximumsizeofaggregatesshallinnocaseexceed12mm.

(3)Water

Watershouldbefreefromchlorides,sulphates,othersaltsandorganicmatter.Potablewaterwillbegenerallysuitable.

(4)Admixtures

AdmixturesshouldnotcontainCalciumChlorideorotherchloridesandsaltswhicharelikelytopromotecorrosionofprestressingsteel.

(5)PrestressingSteel

Theprestressingsteelwires,includingthoseusedasuntensionedwiresshouldconformtoIS:1785(PartI)1966(Specificationforplainharddrawnsteelwireforprestressedconcrete.PartIcolddrawnstressrelievedwire),IS:1785(PartII)1967(Specificationforplainharddrawnsteelwire).,orIS:60031970(Specificationforindentedwireforprestressedconcrete).ThetypedesignsgiveninAnnexureIareforplainwiresof4mmdiameterwithaguaranteedultimatestrengthof175Kg/mm2.

(6)Theconcretemix:

Itshallbedesignedtotherequirementslaiddownforcontrolledconcrete(alsocalleddesignmixconcrete)inIS:13431980(Codeofpracticeforprestressedconcrete)andIS:4561978(Codeofpracticeforplainandreinforcedconcrete),subjecttothefollowingspecialconditions;

1. Minimumworkscubestrengthat28daysshouldbeatleast420Kg/cm2.2. Theconcretestrengthattransfershouldbeatleast210Kg/cm2.3. Themixshouldcontainatleast380Kg.ofcementpercubicmeterofconcrete.4. Themixshouldcontainaslowawatercontentasisconsistentwithadequateworkability.Ifitbecomesnecessarytoaddwaterto

increasetheworkability,thecementcontentalsoshouldberaisedinsuchawaythattheoriginalvalueofwatercementratioismaintained.

DesignRequirementsforPCCPole::

Thepolesshallbeplanteddirectlyinthegroundwithaplantingdepthof1.5meters.Theworkingloadonthepolesshouldcorrespondtothosethatarelikelytocomeonthepoleduringtheirservicelife.DesignsgiveninAnnexureIarefor140Kg.and200Kg.Appliedat0.6Mfromtop.Thefactorofsafetyforallthesepolesshallnotbelessthan2.5.Theaveragepermanentloadshouldbe40%oftheworkingload.TheF.O.S.againstfirstcrackloadshallbe1.0.Ataveragepermanentload,permissibletensilestressinconcreteshallbe30Kg/cm2.Atthedesignvalueoffirstcrackload,themodulusofruptureshallnotexceed55.2kg/cm2forM420concrete.Theultimatemomentcapacityinthelongitudinaldirectionshouldbeatleastonefourthofthatinthetransversedirection.Themaximumcompressivestressinconcreteatthetimeoftransferofprestressshouldnotexceed0.8timesthecubestrength.Theconcretestrengthattransfershallnotbelessthanhalfthe28daysstrengthensuredinthedesign,i.e.420x0.5=210Kg/cm2.Formodelcheckcalculationsonthedesignofpoles,referredtoinAnnexureI,areferencemaybemadetotheRECManualonManufacturingofsolidPCC

DimensionsandReinforcementsforPCCPole:

ThecrosssectionaldimensionsandthedetailsofprestressingwireshouldconformtotheparticularsgiveninAnnexureI.TheprovisionsofholesforfixingcrossarmsandotherfixturesshouldconformtotheRECstandardsreferredtoinclause4ofthisspecificationandinaccordancewiththeconstructionpracticesadoptedbytheStateElectricityBoards.

ManufactureforPCCPole::

Allprestressingwiresandreinforcementsshallbeaccuratelyfixedasshowninthedrawingsandmaintainedinpositionduringmanufacture.Theuntensionedreinforcement,asindicatedinthedrawings,shouldbeheldinpositionbytheuseofstirrupswhichshouldgoroundallthewires.Allwiresshallbeaccuratelystretchedwithuniformprestressineachwire.Eachwireorgroupofwiresshallbeanchoredpositivelyduringcasting.Careshallbetakentoseethattheanchoragesdonotyieldbeforetheconcreteattainsthenecessarystrength.

CoverforPCCPole:

Thecoverofconcretemeasuredfromtheoutsideoftheprestressingtendonshallbenormally20mm.

Welding&LappingofSteelforPCCPole:

Thehightensilesteelwireshallbecontinuousovertheentirelengthofthetendon.Weldingshallnotbeallowedinanycase.However,jointingorcouplingmaybepermittedprovidedthestrengthofthejointorcouplingisnotlessthanthestrengthofeachindividualwire.

CompactingforPCCPole:

Concreteshallbecompactedbyspinning,vibrating,shockingorothersuitablemechanicalmeans.Handcompactionshallnotbepermitted.

CuringforPCCPole:

Theconcreteshallbecoveredwithalayerofsacking,canvas,hessianorsimilarabsorbentmaterialandkeptconstantlywetuptothetimewhenthestrengthofconcreteisatleastequaltotheminimumstrengthofconcreteattransferofprestress.Thereafter,thepolemayberemovedfromthemouldandwateredatintervalstopreventsurfacecrackingoftheunit,theintervalshoulddependontheatmospherichumidityandtemperature.

TheprestressingwiresforPCCPole:

Itshallbedetensionedonlyaftertheconcretehasattainedthespecifiedstrengthattransfer(i.e.210Kg/cm2).Thecubescastforthepurposeofdeterminingthestrengthattransfershouldbecured,asfaraspossible,underconditionssimilartothoseunderwhichthepolesarecured.Thetransferstageshallbedeterminedbasedonthedailytestscarriedoutonconcretecubestillthespecifiedstrengthindicatedaboveisreached.ThereafterthetestonconcreteshallbecarriedoutasdetailedinIS:13431960(Codeofpracticeforpre

stressedconcrete).Themanufacturershallsupplywhenrequiredbythepurchaserorhisrepresentative,resultofcompressivetestconductedinaccordancewithIS:4561964(Codeofpracticeforplainandreinforcedconcrete)onconcretecubesmadefromtheconcreteusedforthepoles.Ifthepurchasersodesires,themanufacturershallsupplycubesfortestpurposesandsuchcubesshallbetestedinaccordancewithIS:4561964(Codeofpracticeforplainandreinforcedconcrete).Thedetensioningshallbedonebyslowlyreleasingthewires,withoutimpartingshockorsuddenloadtothepoles.Therateofdetensioningmaybecontrolledbyanysuitablemeanseithermechanical(screwtype)orhydraulic.Thepolesshallnotbedetensionedorreleasedbycuttingtheprestressingwiresusingflamesorbarcropperswhilethewiresarestillundertension.

SeparateeyehooksorholesforPCCPole:

Itshallbeprovidedforhandlingandtransport,oneeachatadistanceof0.15timestheoveralllength,fromeitherendofthepole.Eyehooks,ifprovided,shouldbeproperlyanchoredandshouldbeonthefacethathastheshorterdimensionofthecrosssection.Holes,ifprovidedforliftingpurposes,shouldbeperpendiculartothebroadfaceofthepole.Stackingshouldbedoneinsuchamannerthatthebroadsideofthepoleisvertical.Eachtierinthestackshouldbesupportedontimbersleeperslocatedat0.15timestheoveralllength,measuredfromtheend.Thetimbersupportsinthestackshouldbealignedinaverticalline.Polesshouldbetransportedwiththeirbroadfacesplacedverticallyandinsuchamannerthatshocksareavoided.Supportsshouldbesoarrangedthattheyarelocatedapprox.atadistanceequalto0.15timestheoveralllengthfromtheends.Theerectionofthepoleshouldbecarriedoutinsuchawaythattheerectionloadsareappliedsoastocausemomentwithrespecttothemajoraxis.i.e.theropeusedforhoistingthepoleshouldbeparalleltothebroaderfaceofthepole.

TestingofPCCPole:

TransverseStrengthTest

PolesmadefromordinaryPortlandcementshallbetestedonlyonthecompletionof28daysandpolesmadefromrapidhardeningcementonlyonthecompletionof14days,afterthedayofmanufacture.Thepolemaybetestedineitherhorizontalorverticalposition.Iftestedinhorizontalposition,provisionsshallbemadetocompensatefortheoverhangingweightofthepole,forthispurposetheoverhangingportionofthepolemaybesupportedonamovabletrolleyorsimilardevice.Thepoleshallberigidlysupportedatthebuttendforadistanceequaltotheagreeddepthofplantingi.e.1.5M.Loadshallbeappliedatapoint600mmfromthetopofthepoleandshallbesteadilyandgraduallyincreasedtodesignvalueofthetransverseloadatfirstcrack.Thedeflectionatthisloadshallbemeasured.Aprestressedconcretepoleshallbedeemednottohavepassedthetestifvisiblecracksappearatastagepriortotheapplicationofthedesigntransverseloadforthefirstcrack.Theloadshallthenbereducedtozeroandincreasedgraduallytoaloadequaltothefirstcrackloadplus10%oftheminimumultimatetransverseload,andheldupfor2minutes.Thisprocedureshallberepeateduntiltheloadreachesthevalueof80percentoftheminimumultimatetransverseloadandthereafterincreasedby5percentoftheminimumultimatetransverseloaduntilfailureoccurs.Eachtimetheloadisapplied,itshallbeheldfor2minutes.TheloadappliedtoprestressedconcretepoleatthepointoffailureshallbemeasuredtothenearestfiveKilograms.Thepoleshallbedeemednottohavepassedthetestiftheobservedultimatetransverseloadislessthanthedesignultimatetransverseload.

MeasurementofPoleCoverforPCCPole:

Aftercompletionofthetransversestrengthtest,thesamplepoleshallbetakenandcheckedforcover.Thecoverofthepoleshallbemeasuredat3points,onewithin1.8metersfromthebuttendofthepole,thesecondwithin0.6meterfromthetopandthethirdatanintermediatepointandthemeanvaluecomparedwiththespecifiedvalue.

Themeanvalueofthemeasuredcovershouldnotdifferbymorethan()1mmfromthespecifiedcover.Theindividualvaluesshouldnotdifferbymorethan()3mmfromspecifiedvalue.Iftheserequirementsarenotmet,theworkmanshipwithreferencetoaligningoftheendplatesandprestressingwiresandassemblyofmouldsshouldbeimprovedandinspectionatpreproductionstagetightenedsuitably.

MarkingforPCCPole:

Thepoleshallbeclearlyandindeliblymarkedwiththefollowingparticularseitherduringoraftermanufacturebutbeforetestingatapositionsoastobeeasilyreadaftererectioninposition.

1. Monthandyearofmanufacture2. TransversestrengthofpoleinKg.3. MakersserialNo.andmark

MainPointsshouldbelookafterforOverheadLineInstallation:

Overheadlines:

ThegeneralprecautionsduringstorageandhandlingofshallbetakeninaccordancewithrelevantIScode.Whilelayingtheconductorshallbetakenfromtopofthedrumandtherepeatedinthedirectionofarrowonit..Careshallbetakentoavoidcontactwithsteelworks,fence,etcbygivingsoftwoodprotection,usingwoodenrollers.Propertoolsshallbeusedduringstringingwork.Duringstringingoperationstandardsagtableorchartshallbefollowedandcareshallbetakentoensurethattherearenokinksintheconductor.Jointsinconductorsshallbestaggered.Midspanjointsinconductorsshallbeavoided.Afterstringingtheconductor,itshallbeclampedpermanentlywithshackleorstrainclamps.Anangleorsectionshallbeselectedwhilepullingupconductors.

Jumpers:

Whilestringing,sufficientlengthshallofconductorsbekeptatshackleterminationsformakingjumpers.Jumpersshallbeneatandasfaraspossiblesymmetricaltorunofconductors.Theseshallbemadetopreventoccurrenceoffaultsduetowindorbirds.PGclampsmaybepreferredtobindingofconductorsatjumperlocationorservicetaps.

CrossArms:

ThecrossarmsshallbemadeofMSStructuralsteel.Thelengthofcrossarmsshallbesuitableforaccommodatingthenumberofinsulatorsonthemwithspacingofconductor.Agapofminimum50mmshallbeleftfromthecenterofpinholetoendofcrossarmoneitherside.ThecrossarmshallbecompletewithpoleclampmadeofMSflatofsizenotlessthan50x6mmwithnecessarynuts,bolts,washers,etc.Thelengthofcrossarmforcarryingguardwiresshallalwaysrunnotlessthan300mmbeyondoutermostbareconductorofconfiguration.Crossarmsshallbeproperlyclampedtothesupporttakingintoconsiderationtheorientationoflines.

Porcelaininsulatorsandfittings:

TheporcelaininsulatorsshallbeconfirmingtoIS7311971foroverheadlines.Thisshallbeglazed,crack/burrfree.Theinsulatorshallhaveadequatemechanicalstrength,highdegreeofresistancetoelectricalpunctureandresistancetoclimaticandatmosphericattack.

Allironpartsshallbehotdipgalvanized&alljointsshallbeairtight.Pininsulators/shackleinsulators/discinsulatorsshallbeerectedoncrossarmsandDironclampshallbeusedorasspecifiedbyEngineerincharge.ShackleinsulatorsshallbeusedinconjunctionwithDironclampswhenconfigurationofconductorisvertical.Theseshallalsobeerectedoncrossarmatintermediatesupportincaseoflonglines,deviationfromstraightlines.Careshallbetakenthatinsulatorsarenotdamagedduringerection.

Bindingmaterial:

Bindingofconductorwiththeinsulatorshallbedonewithsoftaluminumwire/conductor.Thebindingofconductortoinsulatorshallbesufficientlyfirmandtighttoensurethatnointermittentcontactdevelops.Theendofbindingwireshallbetightlytwistedinclosespacedspiralaroundtheconductortoensuregoodelectricalcontactandstrengthentheconductor.

Supportsandspacingofpoles:

Supportofoverheadlineshallbeofadequatestrengthconfirminginallrespectstorules76ofIndianelectricityrules.Polespacingandclearancebetweenlowestconductorabovethegroundlevelacross/alongthestreetshallbeinaccordancewithrule85ofIndianelectricityrules.Suitablefoundationshallbeprovidedforerectionofpoles.Thefoundationshallincludeexcavationinalltypesofsoilandrocksandbackfilling,RCC,reinforcement,formwork.Excavationforfoundationsforpoles/stay/strut:Afterthelocationofsupports/stayarepeggedaccurately,theexcavationworkshallbetakenupandcareshouldbetakenwhileexcavatingthatpitsarenotoversized.Thepitshouldbeexcavatedinthedirectionoftheline.Thedepthandsizeofpitshallbesuchthatnormally1/6thofthelengthofpoleisburiedinthegroundandsuitableforfoundationofsupport.Forstaythepositionofpitshallnormallybesuchstaymakesaslargeanangleaspossiblewiththesupportanditshallbeintherangeof40to60degrees.Thelengthofstayrodshallproject450mmabovethegroundlevel.Thepitforstrutshallbelocatedatadistancenotlessthan1.8Mfromthepole.Thedepthofpitshallbesuchthatatleast1.2Mofthestrutisburiedintheground.

Stay/strut:

Staysetshallconsistofstayrod,anchorplate,bowtightened/turnbuckle,thimbles,staywireandstaininsulators.Thestayrodshallbewithstaygripincaseofturnbuckleisusedinsteadofbowtightened.Theentirestaysetassemblyshallbegalvanized.Thestaywireshallbeeither7/4.0mmdiameteror7/3.15mmdiameterGIhavingtensilestrengthofnotlessthan70kgf/sqmmandconfirmingtoIS2141.TTheanchorplateshallbeofMSgalvanizedandnotlessthan300mmx300mmx6.4mmthick.Thestayrod/bucklerodsshallbeminimum16/19mmdiametergalvanizedsteelrodhavingtensilestrengthnotlessthan42kgf/sqmm.Minimumlengthofstayrodandbuckleshallbe1800mmand450mmrespectively.

Erectionstaysets:

TheanchorplateshallbegalvanizedMSplate.Thestayrodwithanchorplateshallbeembeddedincementconcrete1:3:6.Astayshallbeprovidedatallangleandterminalpoles.Doublestayshallbeprovidedatalldeadendsandinsuchcase,theseshallbeasfaraspossibletobesetparalleltoeachother.

Cageguard:

Allmetalsupportsofoverheadlinesandmetallicfittingattachedshallbepermanentlyandeffectivelyearthed.Cageguard/cradleguardshallbemadeof6SWGGIwireconfirmingtoIS2633includingnetting,stretchingandjointingofcageandlacingby10/12SWGGIwire,bindingby14/16SWGGIwire.

Dangerboards:

AllsupportscarryingHVlinesshallbefittedwithdangerplatesconfirmingtoIS2551atheightof3Mfromgroundindicatingthevoltageofline.ThescriptshallbebothinEnglish/Hindi.

Anticlimbingdevices:

NecessaryarrangementforpreventingunauthorizedpersonsfromascendinganyofthesupportsandstructurecarryingHVlineswithouttheaidofladderorspecialapplianceshallbemade.UnlessotherwisespecifiedbarbedwireconfirmingtoIS278havingfourpointsbarbedspaced75+/12mmapartshallbewrappedhelicallywithapitchof75mmaroundthelimbofsupportandfirmlycommencingfromtheheightof3.5Mandupto5or6Masdirectedbytheengineer.

Lightningarrestor:

LightningarrestorsuitableforHTlinesshallbeinstalledoneunitperphaseatterminations,transformerstations,etc.Thedevicesshallbeconnectedaheadoffuseprovidedifany.IndependentearthelectrodeshallbeprovidedforLA.TheearthleadfromearthelectrodetoLAshallbecontinuous.TheLAshallconfirmtoIS3070andshallbenonlineardistributionclass.TheLAshallbenonlineartype,distributionclass,outdoortypesuitableforeffectivelyearthedsystem.TheLAshallconsistoflineterminalstud,earthterminalstud,numberofsparkgapsinserieswithnonlinearresistor,thewholeassemblyhousedinsideahermeticallysealedporcelainbushing.Neoprenerubbergasketshallbeprovidedbetweenmetalcapsandporcelainbushing.Nonlinearresistorshallbesiliconcarbideblocksmetalizedatbothendstoensuregoodelectricalcontactbetweenterminals,nonlinearresistor&sparkgaps.MountingbracketshallbehotdipgalvanizedsuitableformountingLAonstructure.

CableLayingDirectinGround:

Themethodshallbeadoptedwherethecablerouteisthroughopencountry,alongroad/lanes,etcandwherenofrequentexcavationsareencounteredandreexcavationispossiblewithoutaffectingotherwork.

Widthoftrenches:

Thewidthoftrenchforlayingsinglecableshallbe35cmWheremorethanonecablearetobelaidinthesametrenchinhorizontalformation,widthoftrenchshallbeincreasedsuchthattheinteraxialspacingbetweenthecablesfor415voltsshallbe20cmandfor11shallbe35cm.

Depthoftrenches:

Wherecablesarelaidinsingleformation,thetotaldepthoftrenchshallnotbelessthan75cmforcableupto1.1KVgradeandshallnotbelessthan120cmforcableabove1.1KVgrade.Wherevermorethanonetierformationisunavoidableandverticalformationisadopted,thedepthoftrenchshallbeincreasedby30cmforeachadditionaltiertobeformed.

Protectivecovering:

Cablelaidintrenchesshallhavecoveringofcleandrysandnotlessthan170mmabovethebasecushionofsandbeforetheprotectivecoverislaid.ThecablesshallbeprotectedbyBclass/secondclassbrickofnotlessthan20cmx10cmx10cmorprotectivecoverplacedontopofthesandandbothsidesofcableforfulllengthofthecabletothesatisfactionofEngineerincharge.

Backfilling:

Thetrenchesshallbebackfilledwitexcavatedearthfreefromstonesorotherscrapedgeddebrisandshallberammedandwatered,ifnecessary,insuccessivelayersnotexceeding300mmunlessotherwisespecified.

Routemarker:

RoutemarkershallbeprovidedalongstraightrunsofcablesandatpointsofchangeindirectionasapprovedbyEngineerinchargeandingeneralatintervalsnotexceeding100metersinstraightrun.Routemarkershallbemadeoutof100mmx100mmx5mmGI/Alplateboltedorweldedon35mmx35mmx6mmMSangleironof600mmlong.Suchroutemarkersshallbemountedandgroutedparalleltoand0.5meterawayfromthesideoftrench.Theworkcablewithvoltagegradingandsizeofcableshallbeinscribedonthemarker.

(https://electricalnotes.files.wordpress.com/2011/06/crossarm.png)

(https://electricalnotes.files.wordpress.com/2011/06/1.png)

(https://electricalnotes.files.wordpress.com/2011/06/2.png)

(https://electricalnotes.files.wordpress.com/2011/06/3.png)

(https://electricalnotes.files.wordpress.com/2011/06/guystrain.png)

(https://electricalnotes.files.wordpress.com/2011/06/guyset.png)

(https://electricalnotes.files.wordpress.com/2011/06/crimpedtension.png)

(https://electricalnotes.files.wordpress.com/2011/06/straininsulator.png)

(https://electricalnotes.files.wordpress.com/2011/06/pipeearthing.png)

(https://electricalnotes.files.wordpress.com/2011/06/pinins.png)

(https://electricalnotes.files.wordpress.com/2011/06/insulatorpin.png)

(https://electricalnotes.files.wordpress.com/2011/06/dangerboard.png)

(https://electricalnotes.files.wordpress.com/2011/06/dangerboard11kv.png)

FILEDUNDERUNCATEGORIZED

AboutJignesh.ParmarJigneshParmarhascompletedM.Tech(PowerSystemControl),B.E(Electrical)fromGujaratUniversity.Hehasmorethan13yearsexperienceinPowerTransmissionPowerDistributionElectricalenergytheftdetectionElectricalMaintenanceElectricalProjects(PlanningDesigningcoordinationExecution).HeisPresentlyassociatewithoneoftheleadingbusinessgroupasaDeputyManageratAhmedabad,India.HeisFreelancerProgrammerofAdvanceExcelanddesignusefulExcelSheetsofElectricalEngineeringasperIS,NEC,IEC,IEEEcodes.HeistechnicalAuthorforElectricalMirrorandElectricalIndiaMagazines.HeisTechnicalBloggerandFamiliarwithEnglish,Hindi,Gujarati,Frenchlanguages.HewantstoSharehisexperience&knowledgeandhelptechnicalenthusiaststofindsuitablesolutionsandupdatingthemselvesonvariousEngineeringTopics.

101Responsesto11KV/415VOverheadLineSpecification(REC)

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ShonaBalajisays:June14,2011at6:17amexcellent

ReplyEng.Asadsays:March25,2013at8:36amDistancebetweentowpolesof20KVoverheadline.

Replykarthiksays:September2,2011at11:52amawesomesir.itshighlyusefulforeveryelectricalengineer

Replykennyjamessiamesays:September19,2011at9:41pmHi,pleasesendmetheqoutefortheDROPOUTFUSELINKASSEMBLYCOMPLETE,11KV.GivemepricesbothFOBandCIFZambiafor300pieces.Iwaittohearfromyou.ithankyouinanticipation.RegardsKenny.JSKCoLTD

ReplyVinayGhadesays:August6,2014at8:08pmDearSir,

imVinayGhadeBEelectricalengineerhavingaround7yearsexperienceindesigningfield.iwanttogomuchdeeperinthisfield.Anydesigncourseyouofferoranybooksthatistoberefer.

Replydillipkumargarnayaksays:September14,2014at6:49pmgood

Replyvikassays:October3,2011at4:09pmWhatshouldbetheminimumspacingbetweenLToverheadconductors?IsthereanyISorIEruleforthis.

ReplyJignesh.Parmarsays:October6,2011at10:39amYesInbothHorizontalcongu.andforVerticalconfug.200mmforverticalconfu.and300mmforhorizontalconfuforPPthisisindicateinCPWDnoms.PleasereadmyAbstractnotes.Youwillfindit.

Replyvikassays:October4,2011at2:31pmIsthereanyISorIErulespecifyingthespacingbetweentwoconductorsof415Voverheadline.

ReplyJignesh.Parmarsays:October6,2011at10:38amYesInbothHorizontalcongu.andforVerticalconfug.200mmforverticalconfu.and300mmforhorizontalconfuforPPthisisindicateinCPWDnoms.PleasereadmyAbstractnotes.Youwillfindit.

ReplyAnujBhatnagarsays:October20,2011at8:45amHiJignesh,

CanyoupleasesendmethedrawingandspecificationofDeadEndClampandSuspensionClamp.

Thanks,

Anuj

email:

ReplyM.VENKATARAOsays:November20,2011at9:52amDearsirwhatistheminiumdistancefrompoletopolein11kvoverheadtransmissionline?

ReplyJignesh.Parmarsays:November27,2011at3:53pmMinimumDistance???StartfromZeroNormally25Meterto60Meteraccordingtogeographiccondition,TypeofConductor,TypeofPole..

ReplyVASIMSHAIKHsays:November22,2011at5:09amcanuplzgivemecompletedetailsoferection.Rightfrompolepitdimensiontostringing.Lookingforapositivereply.thanks

Replysatheeshsays:December1,2011at6:02amHelloSirhowtocalculatetheDropoutFuseratingfor100KVAtransformer.andformulas..plstellme

Replypaulsonsays:December6,2011at10:51amhowcanweterminatea630KVAtransformerysecondarysidetoLToverheadline.4x400sq.mmcableisrequired.isthereDPstructurerequiredoranyothersolution?

Replydeepeshsahusays:January12,2012at5:43pmitiscompulsorytousetrinangularconfigurationin11kvpole?

canweuserectangularconfiguration?sirplesereply

ReplyM.SATYANARAYANAREDDYsays:January14,2012at2:19amitiscompulsarytomaintainthe90deg(Straight)anglewhen33kvlinecrossingtheroad,anyalternativestoroadcrossingwithabove90deg(cross)

Replyvijaysays:February1,2012at11:18pmmystationswitchyardthatis11/415vlightingarrestorwhichisaheadofhgfusesetisalwaysbusting.andmyswitchyardisunder33KVline.pleasehelpmeoutwhythiswashappening

ReplyPradipsays:February4,2012at9:39amiwanttocalculationofillumenationofstreetlightscheme3kilometerroadlength,wide15mtr.poletopoledistance30mtr.totalno.ofpoles.100nospolerequire.divder(soassumedoublefittimg.,poleheight9mtr.)&howtocalulatevoltagedrop,cableselections.

ReplyA.ALMOHAMADEDsays:

February12,2012at5:41pmcaniknowthemax.loadof11kvfeeder.andthelong

ReplyJignesh.Parmarsays:February13,2012at2:24pmDependson:(1)ConductorSize(Amp)(2)Lengthofline(3)PermissibleVoltageDrop(4)TypeofLoad

Replyk.karthicksays:February28,2012at11:42amwonderfulsir,

ReplyParagsays:April6,2012at8:06amPleaseprovideustotaldetails&drawingsforvcrossarms,straightcrossarms&others.

Thanks,

ReplyMuhammadFarooqKhansays:June7,2012at4:50pmHi,Iwanttocalculatetheconductorsizeof38km11kvOHL.mytotalloadisgiveninA(KVA)whichis21000KVA.Pleasehelpmeout.suggestmeaformulaandsizeofconductor.

ReplyJignesh.Parmarsays:June8,2012at5:03pmCalculate%RegulationfromexcelsheetgiveninExceltools

ReplyMuhammadFarooqKhansays:June9,2012at5:15amthereisnosuchtooltocalculatetheConductorsizeforOVERHEADLINECONDUCTOR.didACSR7/3.40mmcanbeartheabovegivenload?forcaseof11kv

ReplyRollyMondelosays:June18,2012at12:17pmDearsirwhatistheminimumhorizontalandverticaldistancefromstreetlightpoleina32KVoverheadtransmissionline?

ReplyRollyMondelosays:June18,2012at1:08pmsir,alsosendmethestandardhorizontalandverticalclearanceinanyhighvoltagetransmissionline.thankyouandmorepower!

ReplyM.Viswanathansays:June22,2012at12:03pmDearSir,

Irequiredthestructuralfoundationdetailsforthefollowing;1)DPstructurefor11kVlinewith250kVAtransformermountedsingleincomercumoutgoing.2)and11kVEBpost(RCC)

Replysanusays:

August21,2012at8:22amrespectedsir,canupleasetellmefromwhereicangetrecconstructionmanual.andwhichpublisherispublishingthatbook.igraetlyneedthatbook.thanks

ReplyEhsanUllahsays:September1,2012at4:30amDearsir,pleasetellmethedepthof11kvapole.

ReplyJignesh.Parmarsays:September2,2012at3:31am11KVA!!

ReplySharadTaidesays:September21,2012at4:18pmCanupleasetellmethesafesthorizontalandverticaldistancefromthesteelshed.heightofsteelshedis6m&8M

Replyfaucetsays:November1,2012at7:38pmItsinrealityagreatandusefulpieceofinfo.Iamsatisfiedthatyousharedthishelpfulinformationwithus.Pleasekeepusinformedlikethis.Thanksforsharing.

ReplyM.VENKATARAOsays:November2,2012at7:07amSirifphasesequencechangesinHTsideoftransformerthenL.Tsidephasesequencechangesornot?

Replydanielsays:November7,2012at11:38pmcanihvthediagramorpictureofcradleguard?

Replywamidhtahasays:November10,2012at11:37amDearSirineedplease(Electricalpole,span,sag,calculationinexcelsheet)ifyoucansendittomymailthankyouforeward

Replysrinivassays:January9,2013at1:01pmDearsir,pleaseinformationElectricalpole,span,sag,calculationinexcelsheet)electricalinstallationestimating&costing.Thankyou,Regards,srinivasulu.R

Replywamidhtahasays:January12,2013at10:47amDearSirs;areyoucanthisexelsheetfor(Electricalpole,span,sag,calculation)inecessaryneeditiwaityourreplayinmymailthankyouforwardforyourattentioneng.wamidh/iraq

ReplyJignesh.Parmarsays:

January12,2013at2:24pmDearwamidhtaha,IhavenotsuchtypeofExcelSheet..

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ReplyChetanBhavsarsays:March23,2013at7:43amreallygreatgreatinfohelpedinmyprojectthanksalot..!!!!!!!!!!!

ReplyYogeshsays:April8,2013at10:12amDearAll,

Inourproject,sendingendvoltageisaround400Voltsandreceivingendvoltageis360Vfor150MetersOHline.Herewearegetting40Vdropforaverysmalldistance.Letmeknowthereasonforthisvoltagedrop.

ReplyJignesh.Parmarsays:April9,2013at6:07amYourquestionhasinsufficientinformation.1.whatisload.(1w..100w.)2.whichsizeofoverheadconductorhaveyouused.

Replymaheshsays:April24,2013at11:58amhi,disismaheshmyquestion:ifiwanttoundergroundacablewhichisalreadyoverheadedfromthestreetpoletothetransformerofrating250kva,whichsqmmcableihavetouse?

ReplyJignesh.Parmarsays:April25,2013at4:16pmNotgettingyourPoint???

ReplyErGSinghsays:May5,2013at3:26amHelloJignesh,Reallyusefulstuff,canwestartathreaaboutearthingofUGcables?

ReplyJignesh.Parmarsays:May5,2013at4:25amAlreadygiveintheBlogsearchinoldposts

ReplyAFsays:May19,2013at9:15amIndeedveryinformative.Aquestion:Ihaveseenthatthethehorizontaldistancebetweenthe3phases(conductors)of11kVOHlineisnotsame;2phasesarerelativelycloser,ascomparedtothe3rdone.Doesanybodyknowthereason?

ReplyJignesh.Parmarsays:May19,2013at10:37am

Where??Horizontaldistanceshouldbesameinthreephasedistribution..

ReplyNIKUNJCHAUHANsays:May25,2013at4:42amRESPECTEDSIR,IFYOUHAVENOTESOREXCELTOOLABOUTCALCULATIONOFLOADFLOWANALYSISTHENPLEASEUPLOADIT.THANKYOU.

ReplyHRArunsays:June11,2013at9:45amPleaseprovidethesctionaldrawingsofRCC8.0Mtrpole,RCC9.0Mtrpole,PSC9.0Mtrpole

ReplyRafiqsays:June22,2013at11:35amHI,Howmanytransformerscanbeinstalledin11/0.4KVpackageSUBSTATION/?ThankYou

Replydillipkumargarnayaksays:September14,2014at7:02pmHI,Howmanytransformerscanbeinstalledin11/0.4KVpackageSUBSTATIONandalltransformercalculation

ReplyRameshsays:June27,2013at6:40amsir,pleasesendmemaintenancescheduledoublepoleisolationunit

ReplyRajasays:July20,2013at7:25pmReally,greatusetome

ReplyPrabakaranBalaramansays:July25,2013at5:59pmsir,plzsayabouttheclearancedistancebetweenthepoletopoleandalsodistancebetweengroundsurfacetoconductor

ReplyBHAGWANSURYAWANSHIsays:August8,2013at10:03pmTanksforgivingthatmuchinformationIamveryhappytoreadthiscanigetmuchmoreinformationfromyou

ReplySarojaRanjanPattanayaksays:August14,2013at10:13pmDearSir,

A11KVsubstationisinstalledontheroadatadistanceof5ftfrommyresidentialhouseand3feetfrommyboundarywall.RequestyoutomentiontheminimumdistancethatistobemaintainedduringHVsubstationinstallations

Replyjollybhatiasays:August16,2013at7:06amHiCanutellmewhatshouldbethemaximumcurrentwhichwecangetonltsideon11kvlineandwhatshouldbetherattingofthetransformer..

Replys.alisays:September21,2013at6:58am

timetotimeicollectinformationrelatedtomyjobwhichstandsveryhelpfulforme,thanks,thistimeiwantinformationregardingcalculationofsagin11kvtransmissionlineiamdiplomaengineerinelectricalengineeringbyqualificationwithexperience.

Replyvinodsays:October22,2013at8:56amWhethericangetcompleteBillofMaterialfor11KVswitchyardand11KVoverheadtransmissionline

ReplyM.Y.DESAIsays:October29,2013at9:33amHi,Sir.wheather415vmultistrandedwithinsulationaluminumconductorsforoverheadlindavailableinmarket,ifyespl.senddetails.Thanks.

Replyutkalmishrasays:November23,2013at7:25pmrespectedsirsirpleasetellmewhattypeofproblemwilloccurifwellbindingaconductorwithinsulatorbyAACinltline?regardser.UTKALMISHRA

ReplyBadshahMohideensays:December5,2013at5:08amHiMr.Jignesh,

Congratulateforthewebsiteandyourexcellenteffort.Ihaveadoubt,WhetherthejumperscanbeusedasaIsolationpointduringoutagesof11KV&33KVOHLlinesi.e.toisolatesectionofOHL,thejumperscanremovedandusedasisolationpoints.

Replyankushsays:December28,2013at6:08pmthanks

ReplyAshokKr.Thakursays:December30,2013at3:01pmHelloMr.Jignesh,Cudukindlyletmeknowtheweightof6swgGIwirethatisrqdforcageguardof11kvOHL?

ReplySTEWARTMAWANAsays:March27,2014at10:19amHyMrJignesh,cldyouplizkindlyassistonhwcanIcalculatecablesizewhenwiringa600VATXwhichdraws75Aatasupplyof0240230180and100anditsoutputis24Vac

ReplyREHAANHASSANsays:April12,2014at7:30pmInruralareaandpopulationdensityishighandlocalityfullwithbamboosandlargetreesinmagrahatofsouth24parganasofwestbengal.Atthesetypeofplaceswhatisthedistancebetweentwopolesforwringof440saidlinesandalsofor220saidlinesassuggestedanddirectedbygovernment.Andwhatmeasuresshouldbetaken.

Replyangelitocortezsays:June20,2014at8:39pmGooddaysir,pleasecansendmethedistanceoftransmissiontower33kVwithwiresize366.2mmsquareandwhatistherequiredheightoftoweruseinopenareainwellsite(oilandgascompany)

ReplyMarioEnriquezsays:June23,2014at4:00pm

Mr.Jignesh,

Currently,12KValuminumwiresrunoverawaterway290feet,poletopole.Howmuchwiresagistherebetweenthepoles,assumingwireshavebeeninstalledtostandardspecificationsfor12KVdistribution?Whatreductioninwiresagcanbeexpectedifthespanisreducedto220feet?(Thanksforyourimpressivesite.)

Replysunilmanesays:August24,2014at5:15pmIwanttoknow11kvconductorstypesandtheircurrentcapacity.pl.

Replydillipkumargarnayaksays:September14,2014at6:51pm11kvacabulemeserment

ReplyVenusays:August25,2014at6:11amHiJIGNESHineedallcomponentlist(smallcomponentsalsolikefuse)ofdistributionsystemfrom11kvto240vpleasegivemealist

Replyangelitocortezsays:August29,2014at8:40amImsogladtothankyouitsagreatgreatinformationcanigetmoreinformationfromyou.Godblessyoualways.mayiknowthedropvoltageofdifferentsizeofcableineverymeter.andwhatistherequiredsizeofcableiuseforeveryKva

Replyshrikrishnadubeysays:August31,2014at9:23amsirwhyweareusing9kvLAin11kvsystem?

ReplyHidayatsays:September4,2014at7:03pmwhatisC&DFtest.whatisdissipationfactor

ReplyDBDandapatsays:September9,2014at11:44am(i)Ihave11KVO/Hdistributionlineabout1.7KM(only)andeachindividualpolesareearthedwithEarthspikes(Earthresistanceofeachloactionislessthan5Ohm).ButInspectorisinsistingustoprovidecontiniousearthingforthesaidO/HlineasperIErules.IcouldnottracedthesamefromIErulebook.Expectingyourreplyandpossiblehelp.

(ii)Wheredumpersarebeingoperated,whatwillbethegroundclearance(min)for11KVO/Hline

Replyimprasad79says:September12,2014at6:32am(1)Continuousearthwireofpropersizewhichissolidlyearthedatsubstationistorunallalongtherouteofoverheadline.Forreasonofsafetyaftereveryfifthspan,thepoleistobeprovidedwiththeearthfromtheground.Thiswireissolidlyconnectedtotheearthprovidedatthesubstationandlateroneverysixthpoleisearthed.Galvanizedironwireof8SWGorbiggersizeisusedasearthingconductor.Themaximumcontinuityresistanceofearthshouldnotbemorethan5Ohms.

(11)Minimumclearanceofconductorabovegroundwhilecrossingtheroadorapublicthroughfarefor11KVis6.1MeterandVerticalClearanceabovebuildingif11KVlineispassingoveritis3.66Meter.ConsideringadumperofCat777OBDumpTruck(Empty)100tTRK9780x6105x5147,itsheightwillbeapprox5.2Meter.

Usingalltheabovementioneddata,Poleof9Meterwillgiveenoughclearancewhichsufficeyourpurpose.

Replysamansays:October14,2014at7:57amwhyweareusing3insulatorbracetfor11kVA

ReplyKaiserAhmadsays:November20,2014at6:20pmDearSirWhatshouldbetheworkingloadforaPCCPole,9.0MtrlongwithFOS:2.5.Thepolehastobeusedfor11kVlineinawindpressurezoneof75kg/sqmm.

Replyntejeswarsays:November24,2014at2:38amdearsirthisisveryusefulformeandiwant11kv/0.440kvsinglelinediagramofoutdoorsubstation

Replyvinodnaiksays:November24,2014at1:21pmsiriwantRCCpolestandarddrawingforall7.5m,9m,11m..

ReplyDileepKumarSahusays:December9,2014at11:39amWhatisthemeaningofconductornames(ACSRDog,Rabbit&Weasel)?Dotheybelongtospecificvoltagelinerating?

Replyprabirduasays:December15,2014at9:56amIPolitelyrequestyouCanyousendtomealltypeofelectricaliscoadlist.

ReplyVinodRanasays:January8,2015at11:12amMrParmar

ThisisRanafromDelhiHowmuchvoltagedifferenceisallowedineachphasevoltageof11KVline.MyincomingvoltageisshowingRPhase11000VoltsYPhase110100andBphaseis11500volts.Isitpermissible.thesamecorrespondingdifferenceiamgettinginLTalso415,410.400ineachphase.

Howtoresolveit.

Rgs

ReplyVinodRanasays:January8,2015at11:14amPLread110100as11100volts

ReplyAMANsays:January13,2015at2:26amTHANKYOU.ITISVERYHELPFUL.

Replysakthivelsays:January21,2015at3:30ampleasetelmetheinsulatornamewhichusedindpyard

Replytkmishrasays:January29,2015at11:13amR/sweareengagedindistributionsystemdealingwith33kv11kvand440v,workinginmpeb(nowmppkvvclwerequiredtopurchaseitemslocallybutwedonthavesuitablespecificationbook.Canusuggestmesomesuchbooks

ReplySamsonPaulsays:

March13,2015at10:08amHello,

IreallylikethisarticlesinethisarticleissoinformativeformeasIamcurrentlydoingmyfinalyearprojectondesigninga11kVdistributiongridextesionwiththeutilitycompanyinmycountry.

AmafinalyearelectricalengineeringstudentatthePapuaNewGuineaUniversityofTechnology.

Amaskingifyoucouldhelpmewithmyprojectwithnecessaryinformation.

Thankyouverymuch.

Replyraselsays:March20,2015at4:04pmWouldyoupleaseinformmewhatshouldbethestandardheightofa11/.44kvsubstationbuildingasperelectricalrules.

Thanks

ReplyAnandKumarK.S.,Sr.Technicalofficer,ElectricalDivision,CSIRNationalAerospaceLaboratories,Bangaloresays:March27,2015at1:41pmDearsirinformationisveryusefultoprofessionalengineers

ReplyN.NYNARKUMARsays:March31,2015at7:36amDearsir

Iwouldliketothankfultosaytothat,Iamnynarkumariamworkingonrggvyprojectandihavecompleteinoneyear,todayiamstudiedinyourRecspecifications.itisveryvaluableinformationforallsiteengineers.butihaveasmalldoughfortransformerearthingAndLAinstallation.pleasegivemethevaluableanswer.

ReplyD.B.V.R.K.S.Sarmasays:May26,2015at12:11amRespectedsirGoodmorningtheinformationyouhaveprovidedisusefulforeverypersonalwhoisattachedwithelectricaldistributionsystem,thanksforprovidingtheinformation,nowcomingtomydoubti.eIwanttoknowthereasonbehindmaintainingadistanceof1200mminbetweenlinesupportandearthingelectrodeindistributionsystem.

Replyjhulansays:June3,2015at8:14amHowmany9mstpPolerequere1km11kvline

ReplyKashmiraLalsays:July3,2015at7:01amDearJignesh,

Pl.adviseforanymachineorattachmentusedtoerectelectricpoles.

Thanks,Kashmira

ReplyDharmendrasays:July5,2015at4:11amGood

ReplyMUKESHKUMARsays:July7,2015at1:56pm

DearJignesh,

DearJignesh,Isawapairofshieldorgroundwirestrung/runningbelowphaseconductorsin11KVoverheadpowerline.Isthisrequiredina3phase11KV/415voltsoverheaddistributionlines/streetlightingutilitypolesalso;speciallyonstreetcrossing?Idontseeoneinmylocality.Pleaseclarify.

ReplyAmitGuptasays:July10,2015at7:11amHowtolocateafaultin11KVOHlineeasily.TheLineisrunningthroughfarmerslandandsomeoftreetouchestheOHlinecauseearthfaultor/andovercurrentfaultresultintripingthesystem.

Reply

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