CharINWhitePaperMegawattChargingSystem(MCS)

RecommendationsandSpecificationforMCSrelatedstandardsbodiesandsolutionsuppliers

Version2.0

2025-05-08

ChargingInterfaceInitiative(CharIN)e.V.

c/oCharINAcademyGmbHEUREF-Campus10-11

10829Berlin

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RecommendationsandrequirementsforMCSrelatedstandardsbodiesandsolutionsuppliers,Version2.0,2025-04-11

PAGE

10

Contents

Introduction 4

MCSImportancetoBatteryElectricCommercialVehicleIndustry 4

MCSConsiderationsforPubliccharging 4

Provisionsforautomation 4

Requirements 5

Communication 5

ChargingCommunication-PhysicalLayer 5

High-LevelCommunicationApplicationProtocol 8

Electrical 9

Electromagneticcompatibility 9

Isolation&Safety 9

HVTouchSafety 9

Maximumsocket/pintemperatures 10

Contacttemperaturedifferencecomparedtoambient 10

Permissiblesurfacetemperatures 11

Shortcircuitprotection 11

BusVoltageRange 11

MaximumCurrent 12

MinimumCurrent 12

ThermalManagementSystemstoSupportHighCurrents 12

PEPinSize 13

PEWireSize 13

Insulationrequirements 13

Touchcurrentprotection 14

Auxiliarylowvoltagesupply 14

Hardware 15

CouplerRetention 15

EVSE/PortLocationRecommendations 15

Torquerequirement 16

Insertion/ExtractionForce 16

Droptestrequirement 16

Adapters 16

MatingDurability 17

AutomatedConnection 17

IngressProtection 17

Temperaturerestrictedunlock 17

ThermalBoundaryConditions 17

Cable17

Ergonomics 18

Conclusion 19

Reference 20

Introduction

Thisdocumentgivesanoverviewofseveraltechnicalandnon-technicalaspectsoftheMegawattChargingSystem(MCS),asdiscussedwithintheCharINSubgroupsince2018.Asadescriptivesummary,itprovidestheachievementsinpreparinggeneraldesignaspectsofanMCS.ForfurtherdevelopmentthisdocumentalsoprovidesrecommendedMCSspecificationsforadoptionbyStandardsDevelopmentOrganizations(SDOs).

MCSImportancetoBatteryElectricCommercialVehicleIndustry

Therearetwokeytechnologiestobroadacceptanceofbatteryelectriccommercialvehicles:increasedrangeanddecreasedchargetimes.Chargingtime,whichcanbequantifiedasdistancepertimeunitcharged,shouldbeconsideredacrossthefleet,andshouldalsoconsiderlostchargingtimeduetodelayedchargingorevenchargingequipmentissues.MCSoffersthechargeratenecessarytorealizewidespreadadoptionofbatteryelectrificationinthecommercialvehiclemarketbyincreasingdrivingrangegainedperminutespentcharging.MCSalsooffersimprovedrobustnessofcommunication,whichwillreducedowntimerelatedtofailedchargingevents.

Commercialvehiclesdutycyclesarespecifictotheirapplications.TheincreasedchargerateofferedbyMCSwillallowthevehiclestodrivemoredistanceperdaybyutilizingthemandatedbreak-timefromthehours-of-serviceregulations.Theseregulationsstatethatdriversmusttakeabreakonoccasionduring

theirdrivecycle;theexactamountvariesbylocation,butit’swellunderstoodthatreducingchargingtimestofitintonormalbreaksinthedutycycleisanenablerforimprovedelectrificationforcommercialvehicles.ThisisjustonespecificexampleofhowtheMCSchargeratecanenablethemarket.

MCSConsiderationsforPubliccharging

AccessibilityhastobeconsideredwheninstallingMCSchargersinpublicinfrastructure.MCSisanenablingtechnologytocommercialvehicleelectrification.ItiscriticalthatMCSchargersareaccessiblebylargecommercialvehiclesrequiringdrivethroughcapabilities.PleasehavealookintotheWhitepaper“ChargingSiteRecommendations”ofCharINforfurtherinformation.

Provisionsforautomation

WhilethepredominateimplementationofMCScharginginfrastructureisexpectedtobehuman-operatedchargingconnectors,provisionforautomatedcouplingispossible.

Requirements

ThischaptersummarizesimportantrequirementsdefinedfortheMegawattChargingSystemwithregardstosafety,communicationandhardwareaspects.Thesetechnicalrequirementswerediscussedbynumerousexpertsfromdifferentindustriesandshouldensureasafeandreliablechargingsystem.

Communication

CommunicationtopologyisanimportantpartoftheMCSspecification.FollowingtheOSImodelforcommunication,oneimportantpartoftheworkdoneintheMCSgroupisdefiningaphysicalcommunicationlayer.Chargingsystemsdeployedthroughouttheworldpresentlyusephysicallayerswithdifferenttechnologies,eachwiththeirownprosandcons.CharINmembershavesuccessfullyimplementedimprovementstotheCCSarchitectureformanyyears,whichusespowerline

communication(PLC)withtheHomePlugGreenPHYcommunicationprotocol.This“singleended”PLCusedforCCSsupportedawidevarietyofusecaseswiththebenefitofnotneedingdedicatedconnectionpinsforcommunicationbetweenEVandEVSE.

ChargingCommunication-PhysicalLayer

MCSisdesignedfora6-foldhighercurrentandupto10-foldhigherpowercomparedtoCCS.Therefore,thesingle-endedimplementationoftoday’sPLCwasconsiderednotrobustenoughfortheexpectedincreaseinelectro-magneticinterference(EMI)emissionscomparedwithCCS.

Afterassessingdifferentphysicallayers(includingCAN,Ethernet,PLC),CharINrecommendsadaptingEthernet–specifically10Base-T1S(IEEE802.3),usingthededicatedchargingcommunicationpinsoftheMCSconnector.EthernetnativelysupportstheTCP/IPcommunicationstackaswellasIPV6.Thissolutionassureshighsignalstabilityandimmunitytoelectromagneticdisturbances.

PLCA

ThePhysicalLayerCollisionAvoidance(PLCA)isapartoftheReconciliationSublayer(RS)whichactsasawrapperbetweenthePHYandtheMAClayer,thereforethistechnologyisusedinthe10BASE-T1Stopreventcollisionsofthedataonthephysicallayer.TheISO15118-10recommendsusinghalf-duplexmultidropmodeofcommunicationduetothemajoradvantageonthesame.Theinformationbetweenthenodesissharedviaroundrobinfashion,givingeachnodeanopportunitytotransmitsitsdataoverthebusline.BEACON,COMMIT,DATAandSILENCEarethePLCAvariables.

Figure1PLCAMessagestructure

Source:Source:Physical-LayerCollisionAvoidancein10BASE-T1SAutomotiveEthernet”.Informationavailable:TestHappens-TeledyneLeCroyBlog:Physical-LayerCollisionAvoidancein10Base-T1SAutomotiveEthernet

Themessagestructureisdescribedasfollows:

BEACON:TheBEACONissignaledbythePHYwithnodeID=0,alsoknownasPLCAcoordinatortoindicatethestartofnewPLCAcycle.

COMMIT:TheCOMMITrequestisgeneratedbythePLCAControlstatemachine.Uponthereceptionofthisrequest,CRS(CarrierSense)signalisassertedbyPHY.

SILENCE:OnceaPLCAcoordinatorsendsaBEACONsignaltostartanewPLCAcycle,eachnodeinthenetworkisgrantedatransmitopportunityinaroundrobinfashion.

AdvantagesofPLCAin10BASE-T1SEthernetoverPLCCommunication

ReducedCollisions:ThePLCAworksontheprincipleofCSMA/CA(CarrierSenseMultipleAccess/CollisionAvoidance)comparedtoPLCcommunicationwhichworksontheCSMA/CD(CarrierSenseMultipleAccess/CollisionDetection),wherethelaterbasicallyonlydetectsthecollisioninsteadofavoidingitandduetowhichoncollisionthepacketsaredroppedresultinginslowmodeofcommunicationastheinformationneedstoberetransmitted.

ImprovedThroughput:Duetonocollisions,thenetworkcanhandlemoredatatraffic,leadingtoimprovedoverallefficiencyofthecommunicationcomparedtoPLC.

EnhancedReliability:WiththePLCA,dataaretransmittedinaroundrobinfashion,withoutanycollisionsaseverynodegetsitsequalopportunitytimetotransmittheinformation.AspertheIEEE802.3normandexplicitlymentionedintheISO15118-10itsmandatorytoconfigureitas32-bittimesoneachnode,thereforemakingitareliablemodeofcommunication.

Figure2ComparisonofCSMA/CDandPLCAintermsofthroughputandaccesslatencySource:OnSemi–NCN26010SinglePairEthernet10BASE-T1SProductOverview

Abbreviations:

CSMA/CD:CarrierSenseMultipleAccess/CollisionDetection

PLCA:PhysicalLayerCollisionAvoidance

NodeConfiguration

Figure3SinglePairEthernetwithMultidropmodeofcommunicationSource:ISO15118-10

NodeID=0(EVSE),configuredastheBEACONasthechargingstationcontrollerwouldinitiatethecommunicationoverthebus

NodeID=1(EV),configuredasthevehiclecontrollerwouldthenrespondbacktoanyinformationsentfromtheEVSE.

NodeID=2(Connector),NodeID=3(Inlet)andNodeID=4(Adaptor),theseareoptionalnodeandifrequiredcouldbeusedintheimplementation.

NodeID=5to7arereservedforanyfuturechangesorimplementations.

High-LevelCommunicationApplicationProtocol

ISO15118isthewell-establishedstandardwithmanysubgroupsworkingondifferentimplementationdetails.ISO15118-2manyhasbeeninusethroughoutthechargingindustryformanyyearsbuthadsomelimitationsaswellasdifferentimplementationsduetoinconsistentinterpretationandimplementationofthestandard.Inaddition,otherDINandSAEprotocolsforcommunicationhavealsobeenusedinthechargingindustryformanyyears,butthoseearlierprotocolsalsohaveevenmorelimitationsandlooseinterpretations.

Asaresultofthesignificantlymorecomplexusecasesthatneedsupporting,suchassecurehandlingofpaymentsystemswith“plugandcharge”,flexiblechargemanagementoperationswithfleetsandlargesites,vehicletogridexportpowerneeds,etc.necessitatinganimprovedcommunicationprotocolultimatelyleadingtothedevelopmentofISO15118-20.Thisprotocolhasbeenpublishedandisavailableforusesinceearly2022.

BecauseofthesignificantnumberofimprovementsofferedbyISO15118-20comparedtopreviousprotocols,ISO15118-20representsthemostcompleteandrobustcommunicationprotocolavailableglobally.Asaresult,CharINrecommendsthatMCSusesISO15118-20exclusively,withnoother(older)protocolssupported,toensuretheabsolutehighestlevelofuserexperienceandsecuritytoequipmentusingMCS

1.

WhileISO15118-20mandatesstrongsecuritymeasures,includingtheuseofTLS1.3forencryptedcommunication,itisworthnotingthatcertaindeploymentscenarios—suchasprivateordepot-basedchargingwheretheinfrastructureisunderstrictoperationalcontrol—maynotrequirethesamelevelofnetworksecurityaspubliccharging.Inthesecontrolledenvironments,avoidingtheimplementationofTLS1.3couldsimplifysystemintegration,reducecosts,andacceleratedeployment,providedthatriskassessmentsconfirmadequateprotectionthroughphysicalsecurityandnetworkisolation.Nonetheless,suchexceptionsshouldbeconsideredcarefullyandonacase-by-casebasis,withaclearunderstandingofthepotentialtrade-offsinsecurityandinteroperability.

1ISO15118-20:2022/DAM1:2024,AnnexKfortheMCSservice

Electrical

Electromagneticcompatibility

EMCrobustnessisatthecoreofchargingcommunicationperformance.ThestandardIEC61851-21-2definesthenecessaryrequirements.CharINmembershavefundedstudiesbyindependentlabs/researchorganizationsintotherobustnessoftheMCSsetupusingsinglepairEthernet.Thesetestswereperformedwithdirectlyinjectednoiseprofiles(bulkcurrentinjection(BCI)couplingtests)tosimulatecouplingofnoisefromthetractionvoltagelinesandadjacentcommunicationlines,tosimulatecommonusecases/industryscenarios.Thefailureconditionsforthesetestsweredefinedasthelossofjustonedatapacket,oralatencytimeof>60ms,whichisverystringent.Theresultsofthesestudiesindicatedthatshieldedtwistedpair(STP)isnotnecessary,andthatunshieldedtwistedpair(UTP)isadequatefortheanticipatednoiselevelsatfullpower.

TheseresultsformthebasesoftherecommendationofEthernetinfurthersections.

Isolation&Safety

MCSisdesignedasachargingsystemthatisgalvanicallyisolatedfromthegrid.Allstate-of-the-artelectricalsafetyrequirementsfromISO5474,IEC60664andIEC61851serieswereconsidered.Furtherkeyrequirementsforthesystemdesignare:

LimitationoftransientvoltagesbetweenHV+orHV-toPEto2.5kVbytheEVSE

LimitationoftheYcapacitancesonEVSEandEVsidedependingonthemaximumoperatingvoltage(seechapter

XV

)

HVTouchSafety

InthissectionHVisconsideredas>60Vand<1500VDC.

Highvoltage(HV)touchsafetyisameasureintendedtopreventlivingobjectsfromcontactingconductivepathsthatmayhaveahighvoltageand/orhightemperature.GloballymanygovernmentalbodiesrequireIPXXBforhighvoltageconnectionsthatareoutsideofapassengercompartment.IPXXBisdefinedbyIEC60529andisintendedtopreventadefined“finger”fromcontactinganyhazardsurface.

MCSneverintendstohaveanyhighvoltageexposurewhentheconnectorandinletarenotmated.BasedupontheexperiencewiththeCCSstandardsdevelopmentandthelessonslearnedtowardbroaderadoptionoftheCCSinterfaceinregionswithotherguidelinesrelatedtotouch-safetyprotections,theMCSdesignfollowedtheselearningsandisconstructedtoprovideIPXXBleveloftouchsafety.

Maximumsocket/pintemperatures

Werecommendthatthemaximumtemperaturelimitofthepin/socketcontactsforMCSissetto100°Cduetothefollowingreasons:

Adequatetestingresultsdemonstratethatevenat100°Ccontacttemperature,thepermissiblesurfacetemperaturesdefinedinIEC62196andUL2278aremaintained.(ReferenceVI.)

Increasedagingislessofaconcernwithmaterialsandsurfacetreatmentsavailablenow.

Thecurrentstandardsnecessitatetheuseofcompositematerialswithtemperatureratingsexceeding105°C.TheexistinglimitsofIEC62196andUL2278arebaseduponformermateriallimitstherebynecessitatingamaximumtemperaturelimitof90°C.100°Cwasagreedasacompromisetoprovidedesignmarginbelowthematerialslimitsof105°C

Today,commonlyusedcompositeplasticscanbefoundinhigh-temperaturegradeswithrelativelyhigherworkingtemperatures.Thesegradesofplasticsarenotprohibitivelyexpensiveandwouldallowforacontacttemperatureincreasetowhileremainingwithinworkingtemperaturelimits.

TemperaturesensingisrequiredfortheHVDCcontactsonboththeinletandtheconnector.ThesensorbehaviorshallfollowtherequirementsspecifiedinIECTS63379whenpublished.

Thetypeofsensorshallremainatthediscretionoftheinletandconnectormanufacturers,respectively.

Contacttemperaturedifferencecomparedtoambient

Werecommendthattheretobenospecificrequirementformaximumtemperaturedifferencebetweensocket/pintemperatureandambienttemperatureforMCS.

Existingstandardsspecifyadualrequirement:

Amaximumsocket/pintemperature(e.g.,90°C)and

Amaximumtemperaturedeltabetweenambientandsocket/pintemperature(e.g.,50°C).

CharINdoesnotrecommendtrackingdualrequirementslikethis.Rather,thefocusisonlimitingmaximumabsolutetemperature,thereforeonlyasinglemaximumtemperatureshouldbereferencedandnoreferencetoambienttemperatureisneeded.

Toclarifyanexample,usecase:Ifavehicleischargingin–10°Cambientairconditions,ifadeltatemperatureof50°Cwasconsidered,thiswouldrequirethatmaximumpin/sockettemperaturesremainbelow40°C(duetothe50°Cdeltarequirement).Havingpintemperaturesabove40°Cwouldnotcauseissues,particularlyrelatedtosafety;therefore,weshouldnotlimitthechargingpowerasaresultofthislowambienttemperature.

Permissiblesurfacetemperatures

CharINrecommendsinlinewithexistingstandards:

Themaximumpermissibletemperatureofthosepartsoftheaccessoryandcableassemblythatcanbegraspedduringnormaloperationcarryingtheratedcurrentshallnotexceed:

50°Cformetalparts,

60°Cfornon-metalparts.

Forpartswhichmaybetouchedbutnotgrasped,thepermissibletemperaturesare:60°Cformetalparts,

85°Cfornon-metalparts.

Shortcircuitprotection

Basedontheprospectiveshortcircuitcurrentsfrommultiplebatterypacks,asavailableatthevehicleinlet,theshortcircuitcurrentshouldbelimitedbythevehicletoapeakcurrentof70kAand12MA2sbetweentheDC+andDC-terminals.TheEVsupplyequipmentshalllimitthepeakcurrentto30kAand1MA2satthevehicleconnector.Incaseoftwoindependentfaults(oneinthevehicleandoneintheEVsupplyequipment)ashortcircuitcurrentmayflowthroughtheprotectiveconductor.Basedontheaddedimpedanceofthechargingcable,thepeakcurrentwillbelimitedto55kA,and11MA2s.TheEVandEVSE,includingthelockedcoupler,shallbedesignedtowithstandthesecurrents.TheinductanceoftheEVSEoutputcircuitandofthevehicleshallbelimitedincoordinationwiththeshortcircuitprotectivedevices.

ProvisionallytheinductanceoftheEVSEoutputcircuitis100μHandfortheEVitisforeseentobebetween30-50μH.

BusVoltageRange

Theoperatingvoltagerangeforachargingsystem(whichincludestheEVSEandEV)mustbeestablishedwhileconsideringaverycomplexamountofinformation.ThiscomplicatedselectionconsidersmetricssuchasavailabilityofpowerelectronicsequipmentforbothEVandEVSE,coverageofvehicleapplications,operatingefficiencyacrossthefleetusage,maximumpoweravailable,addressinghighvoltagesafety,andbalancingthechallengeofsimplifyingpowerelectronicsarchitectureswhilemeetingtheneedsoftheusecasesandoptimizingvaluefordevelopingandmanufacturingEVSEandEV.

TheindustryhasexperiencewithCCSdevelopmentinthepastwithoperatingrangesbetweenapproximately200-920VDC.Wideroperatingranges(aslowas50VDCandashighas1000VDC)aredocumentedaspossiblebutaren’timplementedintypicalinstallations.ThisisausefulreferencewhenconsideringpastandpresentstateoftheartcomparedtofutureexpectationsforMCS.

WhenconsideringthevoltagelevelsthatMCSmustsupport,CharINconsidersthemostimportantfactorstobesupportingasmanyvehiclesaspossible(wideroperatingvoltagerangeisbetter)whilebalancingthatwiththetotaloperatingrange(wideroperatingvoltagerangeincreasescomplexity).Alternativeswereconsidered,suchasreducedoperatingperformancewithhigher/lowervoltagesneeded

duetouniqueoperatingmodesorbatterycellchemistries.ButthosealternativesarenotrecommendedbyCharIN.

Withthoseconsiderations,CharINrecommendsthatMCSshoulduseaminimumvoltageof400VDCandamaximumoperationalvoltageof1250VDC.

ItisimportanttonotethatCharINrecommendsthatallMCSEVSEssupportthefulloperatingrangeof400-1250VDC.Pastexperienceofthee-Mobilitymarketshasshownthattheoperatingvoltagerangecompatibilityisamusttoavoidincompatibilitybetweenvehiclesandinfrastructure.Therefore,EVSEmanufacturersarestronglyadvisedagainstsupportingdevelopmentofMCSEVSEthatcan’tsupportthefullrangeof400-1250volts.

Note:TheConnectorisdesignedfor1500VDC.Systemvoltagewith1500VDCisunderconsiderationwithIEC61851-23-3.

MaximumCurrent

ThemaximumcontinuousratingforMCShasbeentestedupto3000ADC.Considerationsforshort-term,duty-cycleratingsweredeferredforfutureMCSdevelopmentandtesting.Highercurrentsshouldbecarefullyexaminedandvalidatedagainstsafetyrequirements.

Note:Activecoolingisrecommendedforhighercurrents,forcablesaswellasconnectorsandinlets.

MinimumCurrent

TheminimumcurrentsupportedbyMCSshallbedeterminedbythemaximumallowablepermissibleerroraccordingtoIEC61851-23-3asdefinedinCC6.2.BecauseMCSusesISO15118-20,the0AmodeaccordingtoCC.5.5.2shallbesupported.

ThermalManagementSystemstoSupportHighCurrents

Thefollowingtworequirementsclearlydefinethedivisionofresponsibilitywithregardtothermalsystemsduringcharging

Thevehicleisresponsibleforcomplyingwithtemperaturerequirementsforthevehicle.

TheEVSEisresponsibleforcomplyingwithtemperaturerequirementsfortheEVSE(includingcable/connector).

Eachmanufacturerisempoweredtochoosethethermalmanagementsystemoftheirchoice,solongastheymeetthetemperaturerequirements(limits)forMCS.

CharINproposesthatthechargingcurrentandvoltagelimitsoftheEVSEshallbecommunicatedtotheEVandtheEVcontrolshowmuchcurrentisrequestedduringchargingperISO15118-20.

Toensurethatcustomerexpectationsaremetatawidevarietyofoperatingconditions,theEVSEshouldbedesignedinawaysuchthatpowerratingsareprovidedatambienttemperaturesupto40°C.

PEPinSize

8mmdiameterisusedintheMCSconnectordesignforthePEpin.

PEWireSize

ThepotentialequalizationwireincludedintheMCSconnectorfollowstheindustrystandardthatisalreadywellestablishedinhighvoltageconnection,allowingasafepathforhighvoltageshortcircuitcurrentsthroughtheconnectorassemblyfordefinedconditions.

Thecableshallbecapableofwithstandingashortcircuitcurrentof11MA2s,whichtypicallyresultsinaminimumcrosssectionof25mm2.

Insulationrequirements

TheelectricalinsulationrequirementsfortheMCSchargingsystemarederivedfromtheexistingStandardswithappropriateamendmentstoaddresstheincreasedMCSchargingpowerlevels.TherelevantStandardsincludeISO5474forEVs;IEC61851-1andIEC61851-23-3(underdevelopment)forEVSEs;andIECTS63379(underdevelopment)forthechargingconnectorandvehicleinlet.

Touchcurrentprotection

Limitingthetouchenergyasanadditionalprotectionprovisionisanestablishedrequirementinthepublishedstagesofthe2ndeditionofIEC61851-23.DuetothehigherpowerlevelsprovidedbyMCS,higherYcapacitanceswillbeneededinthesystem.TherearevariousconceptstoallowfortheneededYcapacitancesbystillstayingbelowthecriticallimits.

CharINproposestheselimits:

Table1CharINproposedY-capacitancelimits

Vdc+toVdc-

Cysystem(μF)

CyEVtotal(μF)

CyEVperDCline(μF)

1078<Vdc≤1250

ln(0,5???????+75

0,5? 758 )

?0,007

0,5?????????????????

0,25?????????????????

Vdc≤1078

30

15

7,5

thec1limitoffigure22(DC)ofIEC604791(moreconservativethanc1infigure20(AC))

withahumanbodyresistanceof575?

Seeclause8.105.1ofIEC61851-23-3(indevelopment)

Auxiliarylowvoltagesupply

Whenconsideringusecases,CharINreviewedthepossibletechnicalsolutionsofimplementinganauxiliarylowvoltagesupplyinthesystem.ThiswouldbeconsideredashelpfulforusecaseswheretheEVSEorEVdonothavelowvoltageavailableforbasiccommunicationsinordertosupportchargingorexportpowerfeatures(suchasvehicle-to-grid(V2G)incaseofapoweroutage).Afterreviewingthetechnicalconceptsandchallengesassociatedwithdifferentoptions,theconclusionisthatalowvoltageauxiliarysupplyintegratedwiththeMCSconnectorisnotrecommendedasarequirementbutshouldbeconsideredasanoptionalfeaturethatshallnotimpactthefunctionofthecommunicationschemeutilizingthesamecircuit(s).WhenthereisnoauxiliarylowvoltagesupplyintegratedwithMCS,ifanEVSEneedsanabilitytocommunicateforsupportingVehicle-to-gridoperations,theEVSEshouldbesuppliedwithanuninterruptablepowersupply(UPS)orsimilar.Incaseavehiclehasalowvoltagebatteryproblemsuchthatitcan’tbegincharging,itisrecommendedtofollowtheindustrystandardofusing“jumper”cablesora“jumpbox”totemporarilyprovidelowvoltagepowertothatvehicleuntilitcanbegincharging.

Hardware

CouplerRetention

TherearemanylessonslearnedfromthedifferentimplementationsofCCSretainingmeansandlatches,whichincludedbothmechanicalandelectricalinterlockmechanisms,controlledbyindividualusersandalsobyelectronicdevices.TherecommendedMCSretentionisbasedonthoselessonslearned.

TheMCSinterfaceshallincludeanelectricallyactivated/actuatedlocktoensurethattheconnectorremainsengagedwiththeinletduringallnormaloperationandalsoincaseofshortcircuit.ThiselectricallyactivatedretainingmeansshallprovidefeedbacktotheEVandshallbecontrolledindependentlyofbuttonsorswitchesusedforeithernormaluserrequestedshutdownsoremergencyshutdowns.TheretainingmeansshallbeintegratedintotheinletsideoftheMCScoupleronatleastonelocation,andupto3locations,asincludedintheMCSconnectordimensionproposals.Thelockshallhaveapinorslotdesignthatoperatesconsistentlyinallexpectedoperatingconditions,especiallyconsideringtemperatureandweathervariationsforchargingoperationsinextremeenvironments,andwithexpectedtolerancesandwear.

EVSE/PortLocationRecommendations

CharINexpectsthatMCSwillbeusedonmanydifferentvehicleswithmanydifferentusecasesandconfigurations.CharINrecommendsthatfortrucks,theinletlocationshouldbeontheleftsideofthevehicle,behindthemost-forwardaxle.Thisconsistentlocationsupportsbestpracticesfromexperienceswithearlydevelopmentandlessonslearnedfrompreviouschargingexperiences.

AsurveyamongthevehiclemanufacturerswithintheMCSSubgroupresultedininletpositionsbetween2mand4,8m,measuredfromthefrontofthevehicle.

Figure4OutcomeanalysisMCSinletpositionfortrucks

ThefuturereadinessofMCSiscloselylinkedtotheintegrationofautomatedElectricVehicleSupplyEquipment(aEVSE)technology.Astheindustrymovestowardautomatedsolutions,itbecomes

increasinglyimportanttodefinethedatumplaneanddatumaxisfortheinletatanearlystageofdevelopment.Thesestandardizedreferencepointsenableprecisepositioningandalignmentforautomateddockingandundocking,aswellasintegrationwithAutomatedVehicleDockingSystems(AVDS)asspecifiedinISO12768-1.

ByadoptingstandardizedinletpositioningandaccommodatingaEVSEintegrationfromtheoutset,MCStechnologycanbettersupportautonomoustruckingandlong-haulapplications,whereautomatedchargingsolutionswillplayavitalrole.HarmonizingMCSdesignwithemergingautomationtechnologiesensuresfuturereadinessand