article 690 - solar photovoltaic (pv) systems · pdf filearticle 690 - solar photovoltaic (pv)...

2016AllStarTraining,Inc.

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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.

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