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NEC 2017 Code Changes Chapter 6- Special Equipment
Changesfromthe2014codearehighlightedinyellow. ARTICLE 690 - Solar Photovoltaic (PV) Systems PartI.General690.1Scope.ThisarticleappliestosolarPV
systems,otherthanthosecoveredbyArticle691,
includingthearraycircuit(s),inverter(s),and
controller(s)forsuchsystems.[SeeFigure690.1(a)
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andFigure690.1(b).]Thesystemscoveredbythisarticlemaybeinteractivewithother
electricalpowerproductionsourcesorstand-aloneorboth,andmayormaynotbeconnected
toenergystoragesystemssuchasbatteries.ThesePVsystemsmayhaveacordcoutputfor
utilization.
InformationalNote:Article691coverstheinstallationoflargescalePVelectricsupplystations.
690.2Definitions.
Alternating-Current(ac)Module(Alternating-CurrentPhotovoltaicModule).Acomplete,
environmentallyprotectedunitconsistingofsolarcells,optics,inverter,andothercomponents,
exclusiveoftracker,designedtogenerateacpowerwhenexposedtosunlight.
Array.Amechanicallyintegratedassemblyofmodule(s)orpanel(s)withasupportstructure
andfoundation,tracker,andothercomponents,asrequired,toformadcoracpower
producingunit.centertap.
BipolarPhotovoltaicArray.AdcPVarraythathastwooutputs,eachhavingoppositepolarity
toacommonreferencepointorcentertap.
DC-to-DCConverter.AdeviceinstalledinthePVsourcecircuitorPVoutputcircuitthatcan
provideanoutputdcvoltageandcurrentatahigherorlowervaluethantheinputdcvoltage
andcurrent.
DC-to-DCConverterOutputCircuit.Circuitconductorsbetweenthedc-to-dcconvertersource
circuit(s)andtheinverterordcutilizationequipment.
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DC-to-DCConverterSourceCircuit.Circuitsbetweendc-to-dcconvertersandfromdc-to-dc
converterstothecommonconnectionpoint(s)ofthedcsystem.
Direct-Current(dc)Combiner.AdeviceusedinthePVsourceandPVoutputcircuitstocombine
twoormoredccircuitinputsandprovideonedccircuitoutput.
DiversionChargeController.Equipmentthatregulatesthechargingprocessofabatteryby
divertingpowerfromenergystoragetodirect-currentoralternating-currentloadsortoan
interconnectedutilityservice.
ElectricalProductionandDistributionNetwork.Apowerproduction,distribution,and
utilizationsystem,suchasautilitysystemandconnectedloads,thatisexternaltoandnot
controlledbythePVpowersystem.
FunctionalGroundedPVSystem.APVsystemthathasanelectricalreferencetogroundthatis
notsolidlygrounded.
InformationalNote:AfunctionalgroundedPVsystemisoftenconnectedtogroundthrougha
fuse,circuitbreaker,resistancedevice,non-isolatedgroundedaccircuit,orelectronicmeans
thatispartofalistedground-faultprotectionsystem.Conductorsinthesesystemsthatare
normallyatgroundpotentialmayhavevoltagetogroundduringfaultconditions.
GeneratingCapacity.Thesumofparallel-connectedinvertermaximumcontinuousoutput
powerat40°Cinkilowatts.
InteractiveSystem.APVsystemthatoperatesinparallelwithandmaydeliverpowertoan
electricalproductionanddistributionnetwork.
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InteractiveInverterOutputCircuit.Theconductorsbetweentheinteractiveinverterandthe
serviceequipmentoranotherelectricalpowerproductionanddistributionnetwork.
Inverter.Equipmentthatisusedtochangevoltagelevelorwaveform,orboth,ofelectrical
energy.Commonly,aninverter[alsoknownasapowerconditioningunit(PCU)orpower
conversionsystem(PCS)]isadevicethatchangesdcinputtoanacoutput.Invertersmayalso
functionasbatterychargersthatusealternatingcurrentfromanothersourceandconvertit
intodirectcurrentforchargingbatteries.
InverterInputCircuit.Conductorsconnectedtothedcinputofaninverter.
InverterOutputCircuit.Conductorsconnectedtotheacoutputofaninverter.
Module.Acomplete,environmentallyprotectedunitconsistingofsolarcells,optics,andother
components,exclusiveoftracker,designedtogeneratedcpowerwhenexposedtosunlight.
MonopoleSubarray.APVsubarraythathastwoconductorsintheoutputcircuit,onepositive
(+)andonenegative(−).TwomonopolePVsubarraysareusedtoformabipolarPVarray.
MultimodeInverter.Equipmenthavingthecapabilitiesofboththeinteractiveinverterandthe
stand-aloneinverter.
Panel.Acollectionofmodulesmechanicallyfastenedtogether,wired,anddesignedtoprovide
afield-installableunit.
PhotovoltaicOutputCircuit.CircuitconductorsbetweenthePVsourcecircuit(s)andthe
inverterordcutilizationequipment.
PhotovoltaicPowerSource.Anarrayoraggregateofarraysthatgeneratesdcpoweratsystem
voltageandcurrent.
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PhotovoltaicSourceCircuit.Circuitsbetweenmodulesandfrommodulestothecommon
connectionpoint(s)ofthedcsystem.
PhotovoltaicSystemDCCircuit.AnydcconductorsuppliedbyaPVpowersource,includingPV
sourcecircuits,PVoutputcircuits,dc-to-dcconvertersourcecircuits,ordc-to-dcconverter
outputcircuits.
SolarCell.ThebasicPVdevicethatgenerateselectricitywhenexposedtolight.
Stand-AloneSystem.AsolarPVsystemthatsuppliespowerindependentlyofanelectrical
productionanddistributionnetwork.
Subarray.AnelectricalsubsetofaPVarray.
690.4GeneralRequirements.
(A)PhotovoltaicSystems.Photovoltaicsystemsshallbepermittedtosupplyabuildingorother
structureinadditiontoanyotherelectricalsupplysystem(s).
(B)Equipment.Inverters,motorgenerators,PVmodules,PVpanels,acmodules,dccombiners,
dc-to-dcconverters,andchargecontrollersintendedforuseinPVsystemsshallbelistedor
fieldlabeledforthePVapplication.
(C)QualifiedPersonnel.Theinstallationofequipmentandallassociatedwiringand
interconnectionsshallbeperformedonlybyqualifiedpersons.
InformationalNote:SeeArticle100forthedefinitionofqualifiedperson.
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(D)MultiplePVSystems.MultiplePVsystemsshallbepermittedtobeinstalledinoronasingle
buildingorstructure.WherethePVsystemsareremotelylocatedfromeachother,adirectory
inaccordancewith705.10shallbeprovidedateachPVsystemdisconnectingmeans.
(E)LocationsNotPermitted.PVsystemequipmentanddisconnectingmeansshallnotbe
installedinbathrooms.
690.6Alternating-Current(ac)Modules.
(A)PhotovoltaicSourceCircuits.TherequirementsofArticle690pertainingtoPVsource
circuitsshallnotapplytoacmodules.ThePVsourcecircuit,conductors,andinvertersshallbe
consideredasinternalwiringofanacmodule.
(B)InverterOutputCircuit.Theoutputofanacmoduleshallbeconsideredaninverteroutput
circuit.
PartII.CircuitRequirements
690.7MaximumVoltage.ThemaximumvoltageofPVsystemdccircuitsshallbethehighest
voltagebetweenanytwocircuitconductorsoranyconductorandground.PVsystemdccircuits
onorinone-andtwo-familydwellingsshallbepermittedtohaveamaximumvoltageof600
voltsorless.PVsystemdccircuitsonorinothertypesofbuildingsshallbepermittedtohavea
maximumvoltageof1000voltsorless.Wherenotlocatedonorinbuildings,listeddcPV
equipment,ratedatamaximumvoltageof1500voltsorless,shallnotberequiredtocomply
withPartsIIandIIIofArticle490.
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(A)PhotovoltaicSourceandOutputCircuits.InadcPVsourcecircuitoroutputcircuit,the
maximumPVsystemvoltageforthatcircuitshallbecalculatedinaccordancewithoneofthe
followingmethods:
InformationalNote:Onesourceforlowest-expected,ambienttemperaturedesigndatafor
variouslocationsisthechaptertitledExtremeAnnualMeanMinimumDesignDryBulb
TemperaturefoundintheASHRAEHandbookFundamentals,2013.Thesetemperaturedatacan
beusedtocalculatemaximumvoltage.
(1)Instructionsinlistingorlabelingofthemodule:ThesumofthePVmodule–rated
opencircuitvoltageoftheseriesconnectedmodulescorrectedforthelowestexpected
ambienttemperatureusingtheopen-circuitvoltagetemperaturecoefficientsin
accordancewiththeinstructionsincludedinthelistingorlabelingofthemodule
(2) Crystalline and multi-crystalline
modules: For crystalline and multi-
crystalline siliconmodules, the sumof
the PV module–rated open-circuit
voltage of the series connected
modules corrected for the lowest
expected ambient temperature using
thecorrectionfactorprovidedinTable
690.7(A)
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(3)PVsystemsof100kWorlarger:ForPVsystemswithageneratingcapacityof100kW
orgreater,adocumentedandstampedPVsystemdesign,usinganindustrystandard
methodandprovidedbyalicensedprofessionalelectricalengineer,shallbepermitted.
InformationalNote:OneindustrystandardmethodforcalculatingmaximumvoltageofaPV
systemispublishedbySandiaNationalLaboratories,referenceSAND2004-3535,Photovoltaic
ArrayPerformanceModel.Themaximumvoltageshallbeusedtodeterminethevoltagerating
ofconductors,cables,disconnects,overcurrentdevices,andotherequipment.
(B)DC-to-DCConverterSourceandOutputCircuits.Inadcto-dcconvertersourceandoutput
circuit,themaximumvoltageshallbecalculatedinaccordancewith690.7(B)(1)or(B)(2).
(1)SingleDC-to-DCConverter.Forcircuitsconnectedtotheoutputofasingledc-to-dc
converter,themaximumvoltageshallbethemaximumratedvoltageoutputofthedc-
to-dcconverter.
(2)TwoorMoreSeriesConnectedDC-to-DCConverters.Forcircuitsconnectedtothe
outputoftwoormoreseriesconnecteddc-to-dcconverters,themaximumvoltageshall
bedeterminedinaccordancewiththeinstructionsincludedinthelistingorlabelingof
thedc-to-dcconverter.Iftheseinstructionsdonotstatetheratedvoltageofseries-
connecteddc-to-dcconverters,themaximumvoltageshallbethesumofthemaximum
ratedvoltageoutputofthedc-to-dcconvertersinseries.
(C)BipolarSourceandOutputCircuits.For2-wiredccircuitsconnectedtobipolarPVarrays,
themaximumvoltageshallbethehighestvoltagebetweenthe2-wirecircuitconductorswhere
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oneconductorofthe2-wirecircuitisconnectedtothefunctionalgroundreference(center
tap).Topreventovervoltageintheeventofaground-faultorarc-fault,thearrayshallbe
isolatedfromthegroundreferenceandisolatedintotwo2-wirecircuits.
690.8CircuitSizingandCurrent.
(A)CalculationofMaximumCircuitCurrent.Themaximumcurrentforthespecificcircuitshall
becalculatedinaccordancewith690.8(A)(1)through(A)(6).
InformationalNote:Wheretherequirementsof690.8(A)(1)and(B)(1)arebothapplied,the
resultingmultiplicationfactoris156percent.
(1)PhotovoltaicSourceCircuitCurrents.Themaximumcurrentshallbecalculatedby
oneofthefollowingmethods:
(1)Thesumofparallel-connectedPVmodule–ratedshortcircuitcurrents
multipliedby125percent
(2)ForPVsystemswithageneratingcapacityof100kWorgreater,a
documentedandstampedPVsystemdesign,usinganindustrystandardmethod
andprovidedbyalicensedprofessionalelectricalengineer,shallbepermitted.
Thecalculatedmaximumcurrentvalueshallbebasedonthehighest3-hour
currentaverageresultingfromthesimulatedlocalirradianceonthePVarray
accountingforelevationandorientation.Thecurrentvalueusedbythismethod
shallnotbelessthan70percentofthevaluecalculatedusing690.8(A)(1)(1).
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InformationalNote:OneindustrystandardmethodforcalculatingmaximumcurrentofaPV
systemisavailablefromSandiaNationalLaboratories,referenceSAND2004-3535,Photovoltaic
ArrayPerformanceModel.ThismodelisusedbytheSystemAdvisorModelsimulationprogram
providedbytheNationalRenewableEnergyLaboratory.
(2)PhotovoltaicOutputCircuitCurrents.Themaximumcurrentshallbethesumof
parallelsourcecircuitmaximumcurrentsascalculatedin690.8(A)(1).
(3)InverterOutputCircuitCurrent.Themaximumcurrentshallbetheinverter
continuousoutputcurrentrating.
(4)Stand-AloneInverterInputCircuitCurrent.Themaximumcurrentshallbethe
stand-alonecontinuousinverterinputcurrentratingwhentheinverterisproducing
ratedpoweratthelowestinputvoltage.
(5)DC-to-DCConverterSourceCircuitCurrent.Themaximumcurrentshallbethedc-to-
dcconvertercontinuousoutputcurrentrating.
(6)DC-to-DCConverterOutputCircuitCurrent.Themaximumcurrentshallbethesum
ofparallelconnecteddc-to-dcconvertersourcecircuitcurrentsascalculatedin
690.8(A)(5).
(B)ConductorAmpacity.PVsystemcurrentsshallbeconsideredtobecontinuous.Circuit
conductorsshallbesizedtocarrynotlessthanthelargerof690.8(B)(1)or(B)(2)orwhere
protectedbyalistedadjustableelectronicovercurrentprotectivedeviceinaccordance
690.9(B)(3),notlessthanthecurrentin690.8(B)(3).
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(1)BeforeApplicationofAdjustmentandCorrectionFactors.Onehundredtwenty-five
percentofthemaximumcurrentscalculatedin690.8(A)beforetheapplicationof
adjustmentandcorrectionfactors.
Exception:Circuitscontaininganassembly,togetherwithitsovercurrentdevice(s),thatislisted
forcontinuousoperationat100percentofitsratingshallbepermittedtobeusedat100
percentofitsrating.
(2)AfterApplicationofAdjustmentandCorrectionFactors.Themaximumcurrents
calculatedin690.8(A)aftertheapplicationofadjustmentandcorrectionfactors.
(3)AdjustableElectronicOvercurrentProtectiveDevice.Theratingorsettingofan
adjustableelectronicovercurrentprotectivedeviceinstalledinaccordancewith240.6.
(C)SystemswithMultipleDirect-CurrentVoltages.ForaPVpowersourcethathasmultiple
outputcircuitvoltagesandemploysacommon-returnconductor,theampacityofthecommon
returnconductorshallnotbelessthanthesumoftheampereratingsoftheovercurrent
devicesoftheindividualoutputcircuits.
(D)SizingofModuleInterconnectionConductors.Whereasingleovercurrentdeviceisusedto
protectasetoftwoormoreparallel-connectedmodulecircuits,theampacityofeachofthe
moduleinterconnectionconductorsshallnotbelessthanthesumoftheratingofthesingle
overcurrentdeviceplus125percentoftheshort-circuitcurrentfromtheotherparallel
connectedmodules.
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690.9OvercurrentProtection.
(A)CircuitsandEquipment.PVsystemdccircuitandinverteroutputconductorsand
equipmentshallbeprotectedagainstovercurrent.Overcurrentprotectivedevicesshallnotbe
requiredforcircuitswithsufficientampacityforthehighestavailablecurrent.Circuits
connectedtocurrentlimitedsupplies(e.g.,PVmodules,dc-to-dcconverters,interactive
inverteroutputcircuits)andalsoconnectedtosourceshavinghighercurrentavailability(e.g.,
parallelstringsofmodules,utilitypower)shallbeprotectedatthehighercurrentsource
connection.
Exception:AnovercurrentdeviceshallnotberequiredforPVmodulesorPVsourcecircuitordc-
to-dcconverterssourcecircuitconductorssizedinaccordancewith690.8(B)whereoneofthe
followingapplies:
(1)Therearenoexternalsourcessuchasparallel-connectedsourcecircuits,batteries,or
backfeedfrominverters.
(2)Theshort-circuitcurrentsfromallsourcesdonotexceedtheampacityofthe
conductorsandthemaximumovercurrentprotectivedevicesizeratingspecifiedforthe
PVmoduleordcto-dcconverter.
InformationalNote:Photovoltaicsystemdccircuitsarecurrentlimitedcircuitsthatonlyneed
overcurrentprotectionwhenconnectedinparalleltohighercurrentsources.Theovercurrent
deviceisofteninstalledatthehighercurrentsourceendofthecircuit.
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(B)OvercurrentDeviceRatings.OvercurrentdevicesusedinPVsystemdccircuitsshallbe
listedforuseinPVsystems.Overcurrentdevices,whererequired,shallberatedinaccordance
withoneofthefollowing:
(1)Notlessthan125percentofthemaximumcurrentscalculatedin690.8(A).
(2)Anassembly,togetherwithitsovercurrentdevice(s),thatislistedforcontinuous
operationat100percentofitsratingshallbepermittedtobeusedat100percentofits
rating.
(3)Adjustableelectronicovercurrentprotectivedevicesratedorsetinaccordancewith
240.6.
InformationalNote:Someelectronicovercurrentprotectivedevicespreventbackfeedcurrent.
(C)PhotovoltaicSourceandOutputCircuits.Asingleovercurrentprotectivedevice,where
required,shallbepermittedtoprotectthePVmodulesandconductorsofeachsourcecircuitor
theconductorsofeachoutputcircuit.Wheresingleovercurrentprotectiondevicesareusedto
protectPVsourceoroutputcircuits,allovercurrentdevicesshallbeplacedinthesamepolarity
forallcircuitswithinaPVsystem.Theovercurrentdevicesshallbeaccessiblebutshallnotbe
requiredtobereadilyaccessible.
InformationalNote:Duetoimprovedground-faultprotectionrequiredinPVsystemsby
690.41(B),asingleovercurrentprotectivedeviceineitherthepositiveornegativeconductors
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ofaPVsystemincombinationwiththisground-faultprotectionprovidesadequateovercurrent
protection.
(D)PowerTransformers.Overcurrentprotectionforatransformerwithasource(s)oneach
sideshallbeprovidedinaccordancewith450.3byconsideringfirstonesideofthetransformer,
thentheothersideofthetransformer,astheprimary.
Exception:Apowertransformerwithacurrentratingonthesideconnectedtowardthe
interactiveinverteroutput,notlessthantheratedcontinuousoutputcurrentoftheinverter,
shallbepermittedwithoutovercurrentprotectionfromtheinverter.
690.10Stand-AloneSystems.Thewiringsystemconnectedtoastand-alonesystemshallbe
installedinaccordancewith710.15.
690.11Arc-FaultCircuitProtection(DirectCurrent).Photovoltaicsystemsoperatingat80volts
dcorgreaterbetweenanytwoconductorsshallbeprotectedbyalistedPVarc-faultcircuit
interrupterorothersystemcomponentslistedtoprovideequivalentprotection.Thesystem
shalldetectandinterruptarcingfaultsresultingfromafailureintheintendedcontinuityofa
conductor,connection,module,orothersystemcomponentinthePVsystemdccircuits.
InformationalNote:AnnexAincludesthereferenceforthePhotovoltaicDCArc-FaultCircuit
Protectionproductstandard.
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Exception:ForPVsystemsnotinstalledonorinbuildings,PVoutputcircuitsanddc-to-dc
converteroutputcircuitsthataredirectburied,installedinmetallicraceways,orinstalledin
enclosedmetalliccabletraysarepermittedwithoutarc-faultcircuitprotection.Detached
structureswhosesolepurposeistohousePVsystemequipmentshallnotbeconsidered
buildingsaccordingtothisexception.
690.12RapidShutdownofPVSystemsonBuildings.PVsystemcircuitsinstalledonorin
buildingsshallincludearapidshutdownfunctiontoreduceshockhazardforemergency
respondersinaccordancewith690.12(A)through(D).
Exception:GroundmountedPVsystemcircuitsthatenterbuildings,ofwhichthesolepurposeis
tohousePVsystemequipment,shallnotberequiredtocomplywith690.12.
(A)ControlledConductors.RequirementsforcontrolledconductorsshallapplytoPVcircuits
suppliedbythePVsystem.
(B)ControlledLimits.Theuseofthetermarrayboundaryinthissectionisdefinedas305mm
(1ft.)fromthearrayinalldirections.Controlledconductorsoutsidethearrayboundaryshall
complywith690.12(B)(1)andinsidethearrayboundaryshallcomplywith690.12(B)(2).
(1)OutsidetheArrayBoundary.Controlledconductorslocatedoutsidetheboundaryor
morethan1m(3ft.)fromthepointofentryinsideabuildingshallbelimitedtonot
morethan30voltswithin30secondsofrapidshutdowninitiation.Voltageshallbe
measuredbetweenanytwoconductorsandbetweenanyconductorandground.
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(2)InsidetheArrayBoundary.ThePVsystemshallcomplywithoneofthefollowing:
(1)ThePVarrayshallbelistedorfieldlabeledasarapidshutdownPVarray.
SuchaPVarrayshallbeinstalledandusedinaccordancewiththeinstructions
includedwiththerapidshutdownPVarraylistingorfieldlabeling.
InformationalNote:AlistedorfieldlabeledrapidshutdownPVarrayisevaluatedasan
assemblyorsystemasdefinedintheinstallationinstructionstoreducebutnoteliminateriskof
electricshockhazardwithinadamagedPVarrayduringfire-fightingprocedures.Theserapid
shutdownPVarraysaredesignedtoreduceshockhazardsbymethodssuchaslimitingaccess
toenergizedcomponents,reducingthevoltagedifferencebetweenenergizedcomponents,
limitingtheelectriccurrentthatmightflowinanelectricalcircuitinvolvingpersonnelwith
increasedresistanceoftheconductivecircuit,orbyacombinationofsuchmethods.
(2)Controlledconductorslocatedinsidetheboundaryornotmorethan1m(3
ft.)fromthepointofpenetrationofthesurfaceofthebuildingshallbelimitedto
notmorethan80voltswithin30secondsofrapidshutdowninitiation.Voltage
shallbemeasuredbetweenanytwoconductorsandbetweenanyconductorand
ground.
(3)PVarrayswithnoexposedwiringmethods,noexposedconductiveparts,and
installedmorethan2.5m(8ft.)fromexposedgroundedconductivepartsor
groundshallnotberequiredtocomplywith690.12(B)(2).Therequirementof
690.12(B)(2)shallbecomeeffectiveJanuary1,2019.
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(C)InitiationDevice.Theinitiationdevice(s)shallinitiatetherapidshutdownfunctionofthePV
system.Thedevice“off”positionshallindicatethattherapidshutdownfunctionhasbeen
initiatedforallPVsystemsconnectedtothatdevice.Forone-familyandtwo-familydwellings,
aninitiationdevice(s)shallbelocatedatareadilyaccessiblelocationoutsidethebuilding.
Therapidshutdowninitiationdevice(s)shallconsistofatleastoneofthefollowing:
(1)Servicedisconnectingmeans
(2)PVsystemdisconnectingmeans
(3)Readilyaccessibleswitchthatplainlyindicateswhetheritisinthe“off”or“on”
position
InformationalNote:Oneexampleofwhyaninitiationdevicethatcomplieswith690.12(C)(3)
wouldbeusediswhereaPVsystemisconnectedtoanoptionalstandbysystemthatremains
energizeduponlossofutilityvoltage.WheremultiplePVsystemsareinstalledwithrapid
shutdownfunctionsonasingleservice,theinitiationdevice(s)shallconsistofnotmorethansix
switchesorsixsetsofcircuitbreakers,oracombinationofnotmorethansixswitchesandsets
ofcircuitbreakers,mountedinasingleenclosure,orinagroupofseparateenclosures.These
initiationdevice(s)shallinitiatetherapidshutdownofallPVsystemswithrapidshutdown
functionsonthatservice.Whereauxiliaryinitiationdevicesareinstalled,theseauxiliarydevices
shallcontrolallPVsystemswithrapidshutdownfunctionsonthatservice.
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(D)Equipment.Equipmentthatperformstherapidshutdownfunctions,otherthaninitiation
devicessuchaslisteddisconnectswitches,circuitbreakers,orcontrolswitches,shallbelisted
forprovidingrapidshutdownprotection.
InformationalNote:Inverterinputcircuitconductorsoftenremainenergizedforupto5
minuteswithinvertersnotlistedforrapidshutdown.
PartIII.DisconnectingMeans
690.13PhotovoltaicSystemDisconnectingMeans.Meansshallbeprovidedtodisconnectthe
PVsystemfromallwiringsystemsincludingpowersystems,energystoragesystems,and
utilizationequipmentanditsassociatedpremiseswiring.
(A)Location.ThePVsystemdisconnectingmeansshallbeinstalledatareadilyaccessible
location.
InformationalNote:PVsystemsinstalledinaccordancewith690.12addresstheconcerns
relatedtoenergizedconductorsenteringabuilding.
(B)Marking.EachPVsystemdisconnectingmeansshallplainlyindicatewhetherintheopen
(off)orclosed(on)positionandbepermanentlymarked“PVSYSTEMDISCONNECT”or
equivalent.Additionalmarkingsshallbepermittedbaseduponthespecificsystem
configuration.ForPVsystemdisconnectingmeanswherethelineandloadterminalsmaybe
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energizedintheopenposition,thedeviceshallbemarkedwiththefollowingwordsor
equivalent:
WARNINGELECTRICSHOCKHAZARD
TERMINALSONTHELINEANDLOADSIDESMAYBE
ENERGIZEDINTHEOPENPOSITIONThewarningsign(s)orlabel(s)shallcomplywith110.21(B).
(C)SuitableforUse.IfthePVsystemisconnectedtothesupplysideoftheservice
disconnectingmeansaspermittedin230.82(6),thePVsystemdisconnectingmeansshallbe
listedassuitableforuseasserviceequipment.
(D)MaximumNumberofDisconnects.EachPVsystemdisconnectingmeansshallconsistofnot
morethansixswitchesorsixsetsofcircuitbreakers,oracombinationofnotmorethansix
switchesandsetsofcircuitbreakers,mountedinasingleenclosure,orinagroupofseparate
enclosures.AsinglePVsystemdisconnectingmeansshallbepermittedforthecombinedac
outputofoneormoreinvertersoracmodulesinaninteractivesystem.
InformationalNote:ThisrequirementdoesnotlimitthenumberofPVsystemsconnectedtoa
serviceaspermittedin690.4(D).Thisrequirementallowsuptosixdisconnectingmeansto
disconnectasinglePVsystem.ForPVsystemswhereallpowerisconvertedthroughinteractive
inverters,adedicatedcircuitbreaker,in705.12(B)(1),isanexampleofasinglePVsystem
disconnectingmeans.
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(E)Ratings.ThePVsystemdisconnectingmeansshallhaveratingssufficientforthemaximum
circuitcurrentavailableshort-circuitcurrent,andvoltagethatisavailableattheterminalsof
thePVsystemdisconnect.
(F)TypeofDisconnect.
(1)SimultaneousDisconnection.ThePVsystemdisconnectingmeansshall
simultaneouslydisconnectthePVsystemconductorsofthecircuitfromallconductors
ofotherwiringsystems.ThePVsystemdisconnectingmeansshallbeanexternally
operablegeneral-useswitchorcircuitbreaker,orotherapprovedmeans.AdcPV
systemdisconnectingmeansshallbemarkedforuseinPVsystemsorbesuitablefor
backfeedoperation.
(2)DevicesMarked“Line”and“Load.”Devicesmarkedwith“line”and“load”shallnot
bepermittedforbackfeedorreversecurrent.
(3)DC-RatedEnclosedSwitches,Open-TypeSwitches,andLow-VoltagePowerCircuit
Breakers.DC-rated,enclosedswitches,open-typeswitches,andlow-voltagepower
circuitbreakersshallbepermittedforbackfeedoperation.