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F20DLElectric Power Industry Standardof the Peoples RepubKcof ChinaDL/T400—2019Replace DL/T400—2010Technical Guide for Live Working in500kV ACCompact TransmissionLineIssue Date:June4,2019Implementation Date:October1,2019Issued byNational EnergyAdministration of thePeoplesRepublic ofChina
1.
1.5When overhaulingand replacinginsulator stringson the power-off circuitby meansof power-off maintenance,theworkers shallhang andset uppersonal security cables firstbefore installingthe toolsdouble hooksand leverhoists forliftingthe insulator strings.The hangingand dismantlingmethods of the personalsecuritycableare the same asthose of themaintenance earthingcable.
1.
1.6The requirementsand safetyprecautions for working on the ground wire abovethe power-off circuit are thesame asthosewhen bothcircuits arelive.
5.5Work carried out with protective gaps
5.
5.1When the working distanceor combined gap of live workingdoes notmeet the requirements,the workmode ofinstalling protective gaps shall be adopted.
5.
5.2The earthingcable connectedto the protective gaps shall adoptthe multi-strand softcopper wire,and itscross sectionshall meet the requirements ofground shortcircuit capacity,but shall not be less than25mm
2.
5.
5.3When the work iscarried outwith protective gaps,the insulationcoordination between the values of the workingdistance,the combined gap,the minimum effective length of insulating tools and the minimumnumber of good insulatorsand the set values of the protective gaps shall meet therequirements of DL/T
876.
5.
5.4The workerwho installsor disassemblesthe protective gaps shall wear a full set of conductive clothing.
5.
5.5Before the protective gapsare installed,contacting the dispatcher tostop reclosingshall be done.
5.
5.6The protective gapsshall be installedon the adjacent towersto thework location.The earthingcable of eachprotective gapshall bereliably connectedwith the metal componentsof the tower first,and thenthe otherend shall be hungon the conductor of the maintained phase,and thecontact shall be good.The dismantling procedure isreversed.
5.
5.7See Table6for thereference setvalues of the protective gaps.Before the protectivegapsare used,the valuesof theprotectivegaps may be checkedand correctedaccording to the actualsize of the towerhead.Table6Set valuesof the protective gapsAltitudeH/m Setvaluesof theprotectivegaps/mH
10001.21000H
20001.42000H
30001.
65.
5.8During installation,the distance of theprotectivegapshall be adjusted to the maximum value first,and thenthedistance shall beadjustedto thesetvalueof theprotectivegapwith insulating tools after theprotectivegap isinstalled inplace.Before theprotectivegapis dismantled,its distanceshall beset backto themaximumvalue,and thenit shall bedismantled according to thedismantlingprocedure.
5.
5.9For thetwo upperphase conductorsof thethree phaseconductors arrangedin aninverted triangle,theprotectivegapmay bevertically installed between the conductor and the framewhich isbetween thetwo hangingpoints of the V-shapedinsulator string,or maybe horizontallyinstalled between the towerframe and the conductor.In termsof thelower phaseconductor,theprotectivegap maybe horizontallyinstalledbetween the towerframe and the conductor.
5.6Safety protection
5.
6.1The live working safetyprotection equipmentof500kV conventionallines maybe used for live working of500kVcompact lines.
5.
6.2The performanceof the conductive clothing shall complywith GB/T
6568.
5.
6.3Both the equipotential worker and themid-potential worker shallwear a full set ofqualified conductive clothing,andflame resistantunderwear shallalso beworn undertheconductiveclothing.
5.
6.4The ground potential worker on the tower must wearafull set of conductiveclothing or electrostatic protectiveclothing and conductive shoes beforeclimbing the tower.It is strictly prohibited to wearother clothesover conductiveclothingor electrostaticprotective clothing.
5.
6.5The overhead ground wireshall beregarded asa liveconductor,and the workers shallkeep adistanceofover
0.4m fromit.If itis necessaryto workon the overhead groundwire,it shall be groundedwell throughdedicated earthingcables.The methodsand stepsfor installing or dismantling the dedicatedearthing cableson theoverheadgroundwire arethesame asthose forinstallingordismantlingtheearthing cableson apower-off line.
5.
6.6If itis necessaryto enter theoverheadgroundwirefor maintenance,the working distance and mechanical strengthofthe work location afterbearing concentratedload shall be checked.
5.
6.7When usinginsulating ropesto transferlarge metal objectsincluding tools and materials,the workers on the toweror on the groundshall groundthemetalobjects beforetouching them.
5.
6.8With regardto largemetalobjectse.g.automobiles,etc.insulated from the groundand placednear strongelectricfields,attention shall be paidto protectingpeople frominduced electricalinjury.These metalobjects must be groundedbefore they can be touched.
5.6Potential transfer
5.
7.1The equipotential worker shallobtain permissionfrom the person in charge of theworkbefore potentialtransfer.
5.
7.2When the equipotential workertransfers potential,the distance between the human body and the live conductors shallnot be less than
0.4m It isstrictly prohibited totouch the live conductorswith barehands orwith bareparts.
5.
7.3During potentialtransfer,the actionshall besmooth,accurate andfast.6Enter or leave equipotential
6.1Enter or leave equipotentialon asuspension tower
6.
1.1The worker shall notenter orleave equipotentialfrom cross arms verticallyor alonginsulator strings.
6.
1.2The hangingbasket hangingchair andhanging laddermethod,the insulatingflexible laddermethod andothermethods maybe used to enterorleave equipotential.
6.
1.3The hangingbaskets hangingchairs andhanging laddersshall bestably suspendedby slings.The length of theslingsfor fixingshall beaccurately calculatedor actuallymeasured toensure that the equipotential workers headshall notexceedthe gradingring on the conductorside.
6.
1.4The movingspeed of the hangingbaskets hangingchairs andhanging laddersshall bestrictly controlledto achieveauniform andsteady speed.
6.
1.5When entering or leavinghigh electricfields,the equipotential workershallavoid excessivebody movements.All theelectricalgap distancesincluding theworking distancesand thecombined gapsbetween the equipotential workerand theearthing conductors and the liveconductors shall meet therequirements of Chapter
5.
6.2Enter orleave equipotentialon atension tower
6.
2.1The workermay enterorleave equipotential alongtension insulator strings orvia othermethods.
6.
2.2When theequipotential workermoves alongthe tension insulator strings,the cross-two-short-three methodshall begenerallyadopted.The positionsof theworkers hands and feetmust bekept consistent,and thenumber ofinsulatorsshort-circuited by the human body andtools shall meet therequirements ofChapter
5.
6.
2.3The equipotential workers safetybelt shall be tiedto the insulatorstringheld by theworkershandsand shall movesynchronouslywith theworker.
6.
2.4When entering or leavinghigh electricfields,theequipotential workershallavoid excessivebody movements.Allthe electricalgap distancesincluding theworking distancesand thecombined gapsbetween theequipotential workerandthe earthingconductors and theliveconductors,and thenumber of good insulatorsshort-circuited bythe humanbody ortools shall meettherequirements ofChapter
5.7Matters needingattention at work
7.1When live working iscarried out on the tower of500kV ACcompact transmissionlines,a guardianwith specificresponsibilitymust bearranged tostay on the tower.Dedicated communicationtools shall be providedatthework sitetoensure smoothcommunication betweenworkersonand underthetower.
7.2When thephase-to-ground overvoltageof theline is greater than
1.80per unitvalue,theequipotential worker mustadopttheworkmode ofinstallingprotectivegaps whenentering orleaving equipotentialfrom thewindow of the suspensiontower.
7.3Insulating tools shall be usedtotransfer articlesbetween theequipotentialworkerand theworkeron thetowerframe,and theeffective length of the insulating tools shallmeettherequirements of Table
2.
7.4The conductiveclothingshall be free from damage and holes,and allparts ofit shall be connectedwell andreliably.Incase ofdamageandburrs,it shall be sentto aqualified testingunit tomeasure theresistance,fusing currentand screeningefficiencyof the whole set of conductiveclothing,and it can be used only after themeasurement resultsmeet therequirements of GB/T
6568.
7.5Before the insulating toolsare used,an insulationresistance tester2500V〜5000V shall be usedto conductsegmentedinsulation tests.The insulationresistance betweenevery2cm ofmeasuring electrodes shall not beless than700MQ.
7.6The insulating tools shall be protectedfrom moisture,surface damageand surfacedirt whenused.The insulating toolsnot inuse shall be placedon cleanand drypads.
7.7When founddampened,surface-damaged orsurface-dirty,the insulating tools shall be handledin timeand can be usedonlyafter passingthe test.
7.8Before thework starts,metal screwrods,holders andconnecting toolsusedfor live working shall beassembled ontrialand confirmedto beflexible inoperation andreliable inperformance,and shallbeusedcorrectly according to on-siteoperation proceduresorworkinstructions.
7.9The middlejoint of insulating hand sticks shall not beseparated andloosened whenbearing variousloads such as impact,push-pull andtorsion,and the insulating handsticks shall not beused asload-bearing tools.
7.10In use,insulating supportsticks andinsulating tensionsticks must be fixedonthetower with dedicated fixers,and itisstrictly prohibitedto usethese sticksto moveconductors dependingonthe humanbody.
7.11When thework issuspended onthetower,theinsulating handsticksshallbehung verticallyor laidflat onthehorizontal tower materials,and shallnot bedragged onthetowermaterials,so asnot todamage them.
7.12When aninsulatinghandstick isused onthe suspensiontower,it maybe suspendedby aninsulating ropeat aproperposition of the frontpart ofthe stickto preventit from being excessivelybent andreduce thelabor intensityoftheworker.
7.13The diameterofthemouth of a conductorclamp shallbe compatiblewith theouter diameterofthe conductor,andsubstitution isstrictly prohibitedto preventtheconductor frombeingcrushed orslipping.The radiansofthetwo semicirclesof a closedinsulator holdershallbeconsistent with the shapeofthesteel capofthe insulator,so asto avoidlarge stressconcentrationin thestress process.All double-wing holdersshall conformto thespecifications ofcorresponding linkfittings,and shallbe equippedwith backupprotection devicessuchasclosing boltsto preventthem from falling off.Cross armholdersmust adaptto thespecifications ofthetowermaterials,and theassembly ofthem shallbe firm.The specificationsoftension pullersshallbedetermined according to theload and the tensionmode.
7.14In thework ofreplacing suspensioninsulatorstringsor movingconductors,when thesingle suspensionwire deviceisused,there shallbe backupprotection measuresto preventthe conductorsfromfallingoff.
7.15When exchangingand transferringheavy toolsup anddown,the controlrope shallbe fastenedto preventthetransferred objectsfrom collidingwith eachother and accidentally collidingwith thebearing toolsin theworking state.
7.16Insulating ropesshallbekept cleanand dry,andshallbe preventedfrom rubbingagainst thetowermaterials.Dampened insulatingropes arestrictlyprohibitedto beused inlive working.
7.17If zeroand lowresistance insulatorsare foundduring livetesting ofinsulators,they shallbe retested2〜3times.
7.18Before thereplaced insulatorstring isseparated fromtheconductor,when thefirst insulatornear thecross armisdisassembled orinstalled,a dedicatedshort-circuiting wiremustbeused beforedirect operation.
7.19The equipotentialworker musthave backupprotection whenentering orleaving equipotentialand workingatequipotential,and themid-potentialworkermust alsohave backupprotection duringwork.8Test oftools
8.1The designof live working toolsshall conformto therequirementsof GB/T
18037.Conductive clothing,insulatingropes,insulating rods,insulator holders,etc.,shall passtype testsand leavingfactory testsin accordancewith therequirementsof GB/T6568,GB/T13035,GB13398,DL/T463,DL/T
878.
8.2The toolsshallbesubjected toelectrical testsandmechanicaltests ona regularbasis accordingto the test methodsofDL/T
976.The testcycles areas follows:a electricaltests:preventive tests shallbe conducted once a year,and inspectiontests shallbe conducted oncea year,andthe intervalbetween twotestsshallbe halfa year.b mechanicaltests:preventive testsshallbeconductedonceayearfor insulatingtoolsandonce everytwo yearsfor metaltools.
8.3Contents andrequirementsofpreventive testsaPower frequencywithstand voltage test:the testsample shallbe testedentirely;the insulation length ofthe testsamplebetween the test electrodesshallbe
3.7m;the withstand voltage shallbe580kV;the timeshallbe3min.It isqualified ifnobreakdown,flashover oroverheating occur.b Switchingimpulse withstandvoltagetest:the insulationlength ofthetestsample betweenthetestelectrodesshallbe
3.7m;the standardswitching impulsewave+250|is/2500|is shallbe applied;the voltageamplitude shallbe1050kV;thetest sampleshall withstand15times.It isqualified ifno breakdownor flashoveroccur.c Staticload test:a loadof
1.2times theweight ofthe ratedworking loadshallbeapplied forImin.It isqualified ifnopermanent deformationor damageoccur.d Dynamicload test:3times ofactual operationsshallbedone witha loadof
1.0times theweight ofthe ratedworking loadapplied.It isqualified ifthe toolsare flexible,portable and freefromjamming.
8.4Contents andrequirementsofinspection testsaThe insulatingtool shallbe dividedinto severalsections forpower frequencywithstandvoltagetests.A voltageof75kVshall beapplied acrossper300mm oftheinsulatingtool forImin.Itisqualified ifno breakdown,flashover oroverheatingoccur.b Theresistance betweenthe farthestendpoints ofthewholesetof conductiveclothingshallnot be greater than20Q.9Transportation andstorage oftools
9.1During transportation,theinsulatingtoolsshallbe putinto dedicatedtool bags,toolboxes ortool vehiclesin ordertoprevent moistureand damage.
9.2Aluminium alloytools,holders andclamps withlow surfacehardness,and metaltools suchas screwrods thatshouldnot bebumped shallbe transportedwithdedicatedtoolboxes.The capacityof eachbox shallbe limitedto onesetoftools.Scattered partsshallbefixed in the box.
9.3The insulatingtoolsshallbe protectedfrom moisture,rain andblazing sunduring transportation and maintenance.Plastic bagsmaybeused asinner packaging transportation bags,and canvasbags ordedicated leathercanvas boxesmay beusedas outerpackagingtransportationbags.
9.4The live working toolsshallbestored ina dedicateddepot,and thedepot forlive workingtoolsshallmeet therequirementsofDL/T
1.1—2009Directives forstandardization-Part1:Structure anddrafting ofstandards.This standardis arevision ofDL/T400—2010Technical Guidefor Live Working in500kV ACCompact TransmissionLine.Compared withDL/T400—2010,themainchanges areas follows:—the scopeof applicationhas beenexpanded tosingle-circuit anddouble-circuit500kV ACcompact lines at analtitude of3000m and below;—the technical requirements forworking onone power-off circuitwhile theother circuitis livehave beenadded.This standardwas proposedbytheChina ElectricityCouncil.This standardwas preparedbytheNational TechnicalCommittee ofStandardization for Live WorkingSAC/TC
36.Main draftingorganizations of this standard:China Electric Power ResearchInstitute Co.,Ltd,Jinhua PowerSupplyCompany ofState GridZhejiang Electric Power Co.,Ltd,State GridShandong ElectricPower Company,State GridJiangsuElectricPowerCo.,Ltd,and StateGrid HubeiElectricPowerCo.,Ltd.Main draftersof thisstandard:LEI Xinglie,FANG Yuqun,LIU Ting,LIU Kai,SUN Xiaobin,HAN Xuechun,SUNXiaofeng,HUANG Zhenning,MA Jianguo,HU Chuan,PENG Yong,WANG Bin,and QIANLiqun.This standardreplaces DL/T400—2010after implementation.This standardwas issuedon January9,2011as firstedition,and thisis thefirst revisededition.During theprocess ofimplementing thisstandard,relevant opinionsor advicecanbefed backto theStandardizationManagement CenteroftheChina ElectricityCouncil No.l,Lane2,Baiguang Road,Beijing,
100761.Technical Guidefor Live Working in500kV ACCompact TransmissionLine1ScopeThis standardspecifies thetechnicalrequirements,enteringorleaving equipotential,and thetest,transportationandstorageof toolsforliveworking on500kV ACcompact transmissionlines.This standardis applicableto liveworking on500kV single-circuit anddouble-circuit ACcompact transmissionlinesat analtitudeof3000m and below.2Normative referencesThefollowing referenceddocuments areindispensable forthe applicationofthis document.For datedreferences,only theeditioncited applies.For undatedreferences,the latestedition ofthe referenceddocument includingany amendmentsapplies.GB/T
2900.55Electrotechnical Terminology一Live WorkingGB/T6568Screen Clothesfor Live WorkingGB/T13035Live Working一Insulating RopesGB13398Insulating HollowTubes andFoam-Filled Tubesand SolidRods for LiveWorkingGB/T14286LiveWorking-Terminology forTools,Equipment andDevicesGB/T18037Technical Requirementsand DesignGuidefor LiveWorkingToolsGB26859Safety Code of ElectricPowerIndustry一Part of Electric LinesDL/T409Safety Codeof ElectricPower IndustryPartofElectricLinesDL/T463Insulator HolderforLiveWorkingDL/T876Guide ofInsulation CoordinationforLiveWorkingDL/T878Test GuideoftheInsulating ToolforLiveWorkingDL/T974Depot ofTools forLive-WorkingDL/T976Preventive TestCodeofTools,Devices andEquipment forLiveWorking3Terms anddefinitionsFor thepurposes ofthisdocument,the termsanddefinitionsgiveninGB/T
2900.55and GB/T14286as wellas thefollowingapply.
3.1liveworkingwithprotectivegaplive workingcarried outafter installingprotectivegapsin theadjacent towersoftheworklocationto limitovervoltage in thework location4General requirements
4.1Personnel requirements
4.
1.1Live working workers shallbe in good healthandfreefrom physicaland psychologicalobstacles thathinder work.
4.
1.2The liveworking workersshall havea basicknowledge ofelectrical principles,master thebasic principlesandoperating methodsof liveworking,andbe familiar withthe applicationscope andusing methodsof workingtools.Theyshall masteremergency rescuemethods,especially theelectric shockrescue.
4.
1.3The liveworkingworkersshall receivededicated training,pass relevantexaminations andhold relevantcertificates.
4.
1.4The personin chargeofthework orthe guardianshall haveat least3years ofactual workingexperience inliveworking onpower transmissionlines witha voltageclass of500kV and above,befamiliarwith equipmentconditions,andhave certainorganizational capabilityandaccidenthandling ability.
4.2Institutional requirementsAccordingtothe provisions ofandtherelevant institutionsofGB26859and DL
409.
4.3Meteorological requirements
4.
3.1Live workingshallbe carried outingoodweather.In caseof thunder,rain,snow andfog,liveworkingshallnot becarried out.When thewind forceisgreaterthan level5lOm/s,liveworkingshould not becarriedout betweenphases.
4.
3.2Tf liveworking isrequired inweather withrelative humiditygreaterthan80%,insulatingtoolswith moisture-proofperformance shallbeadopted.
4.
3.3Under specialor emergentconditions,if emergent live-line repairmustbecarriedout,thepersonin chargeoftheworkshall organizerelevant personnelto fullydiscuss andformulate reliableorganizational measures,safety measures andtechnical measuresaccordingtothe siteclimate andtheworking conditions,andtheemergentlive-line repaircanbecarriedout onlyafter approval.
4.
3.4In caseofasudden changeof weatherduring liveworking,which mayendanger personalor equipmentsafety,thework shallbe stoppedimmediately.Under thecondition ofensuring personalsafety,the normalworkingconditionsof theequipmentshallberestored assoon aspossible orother measures shallbe taken.
4.4Other requirements
4.
4.1For newliveworkingprojects thatare morecomplicated andmore difficultand newdeveloped tools,scientific testsshallbeconductedto confirmsafety andreliability,and safetymeasuresandoperation processplans shallbe established.Theprojects andtools canbeusedonlyafterapproval.
4.
4.2The personinchargeofliveworkingshallcontact the duty dispatcherbeforethework starts,andthework canbestarted onlyafter contacting.When itis necessaryto disableautomatic reclosing devices,the licenseformalities shallbeperformed.After thework isfinished,reporting tothedutydispatcher shallbedonein time.Itis strictlyprohibitedtostop orresume thereclosingdevicesatanappointed time.5Technical requirements
5.1Maximum overvoltagetimesThe minimumworking distance,the minimumcombinedgapandthe minimumeffectivelengthofinsulatingtoolsfor liveworkingon500kV ACcompact linesshallbedetermined accordingtothemaximum overvoltagetimes atwork.Themaximum overvoltagetimes canbe calculatedaccordingtothe systemparameters.If theexact overvoltagetimes isnotknown,appropriate workgapsshallbe selectedaccordingtothe possiblemaximum overvoltagetimes ofthe500kV system[
2.18per unitvalue].
5.2Ground potentialworking
5.
2.1When theworker worksat groundpotential,the minimumworking distance betweenthe groundpotentialworker onthetower andtheliveconductors shallnot beless thanthe provisionsin Table
1.Table1Minimum working distancebetweenthegroundpotentialworkeronthetower andthe liveconductorsunit:mPhase-to-ground maximumswitching overvoltagetimesper unitvalueAltitude H/m
1.80and belowAbove
1.80H
10003.
03.21000H
20003.
23.42000H
30003.
43.6Note:The valuesin thetable donot includethe spaceoccupied bythe humanbody,which shallnotbeless than
0.5m andshallbe consideredatwork.
5.
2.2The minimumeffective insulationlengthofinsulatingtoolsshallmeetthe provisionsin Table
2.Table2Minimum effective insulationlengthofinsulatingtoolsunit:mInsulating load-bearing toolsAltitudeH/m Insulatinghand sticksandinsulating ropesPhase-to-ground maximumswitching overvoltage
1.80and
1.80andAbove
1.80Above
1.80timesper unitvalue belowbelowH
10003.
53.
73.
23.41000H
20003.
73.
93.
43.62000H
30003.
94.
13.
63.
85.3Bare handworking
5.
3.1When theworker enters or leaves equipotential viainsulatingtools,theminimumcombinedgapshallnotbeless thanthe provisionsin Table
3.Table3Minimum combinedgap ofenteringorleaving equipotentialunit:mPhase-to-ground maximumswitching overvoltagetimesper unitvalueAltitude H/m
1.80and belowAbove
1.80HIQQQ
3.
24.01000W
20003.
44.22000H
30003.
64.4Note:The valuesinthetable donot includethe spaceoccupied bythe humanbody,which shallnotbeless than
0.5m andshallbe consideredatwork.
5.
3.2When theequipotentialworkerentersor leavesequipotentialalong atension insulatorstring,theinsulatorstring shallbetested first.The number ofgoodinsulators shallnotbelessthanthe provisionsof Table4afterthenumber ofinsulatorsshort-circuited bythehumanbodyandbad insulatorsis deductedfromthetensioninsulatorstring.Table4The minimumnumber ofgood insulatorsMinimumtotal lengthofgoodStructure heightofeachThe minimumnumberofgoodAltitude H/minsulators/m insulator/mm insulators
170223.6比
10001951920518170233.81000〈生
20001952020519170244.02000〈生
300019521205205.
3.3The minimumworkingdistancebetweentheequipotentialworkerandtheearthingconductorsshallmeet theprovisions of Table
1.The minimumeffectiveinsulationlengthofinsulatingtoolsshallmeettheprovisionsof Table
2.
5.
3.4The minimumworkingdistancebetweentheequipotentialworkerandtheadjacent liveconductorsshallmeettheprovisionsofTable
5.Table5Minimum workingdistancebetweentheequipotentialworkerandtheadjacent live conductorsunit:mPhase-to-phase maximumswitching overvoltagetimesper unitvalueAltitude H/m
2.80andbelowAbove
2.80佐
10004.
64.81000H
20004.
85.02000/
730005.
05.2Note:The valuesinthetable donot includethe spaceoccupied bythehumanbody,which shallnotbelessthan
0.5m andshallbe consideredatwork.
5.4Work carriedoutonone power-off circuitofadouble-circuit lineonthesame towerwiththeother circuitlive
5.
4.1The workersare notallowed toenterthecrossarmonthelive sideor placeanything onthis crossarm whenworkingon thetower.
5.
4.2When thepower-off circuitpermitted bythedispatcherhas beenchanged tothe maintenancestate i.e.,the substationgroundingswitch hasbeen closed,but thehead endandthetail endofthe circuitarenot groundedor onlyone endisgrounded,this power-off maintenancecircuit shallstill beregarded asa livecircuit,andtheliveworkingmode shallbeadopted forworking.
5.
4.3When bothends ofthecircuitare grounded,itcanbe overhauledby meansof power-off maintenance.The workeronthe conductorwears afullsetofconductiveclothing includinga hat,an uppergarment,a pair of trousers,a pairof gloves,a pairof socksandapairofshoes,thesamebelow,and thendirectly entersorleavestheinsulatorstring orconductorofthemaintained circuit.The workeronthetower bodymustwearafullsetofconductiveclothingorelectrostaticprotectiveclothingandconductiveshoes.
5.
4.4When layingout,withdrawing ortightening aconductor onthepower-off circuit,measuresshallbetakento preventtheconductorfromapproaching theadjacentliveconductors withina dangerousdistance dueto swingingjumping orotherreasons.。
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