GHJ-2000A培訓資料-en課件

TelecommunicationsCompanyofHongtuHigh-Tech

TrainningInformationGHJ-2000AIntelligentDigitalMultiplexingEquipment

1SystemGeneralEquipmentFeaturesDesignPrincipleSystemConfigurationNetworkingMethodIntroductiontoUnitsInstallationandconnectingOperationSafetyProtectionDailyMaintenanceNoticeList2SystemGeneral

ModelGHJ-2000Aintelligentdigitalmultiplexingequipmentisamulti-functionalPCMequipmentwithbuilt-inopticaltransmissionunit,whichcompletestheconnectionbetweenuserterminaldevicesorbetweentheuserterminaldeviceandthepublictelephoneexchangenetworkviaanopticalfibernetworkorothertransmissionmedia.Byutilizingthe2Mdigitalrelayportequippedattheofficesideexchangeortheanalogueuserresources,thisequipmentextendsthevoiceanddataservicestovarioususerareasviaModelGHJ-2000Aintelligentdigitalmultiplexingequipment,toplaytheroleofasmallofficeandrealizenumberdistributionbeyondtheboundary,thuspostponingthebuildingofanewexchangeoffice;orintheurbanarea,itcanovercometherestrictionofdoubletwistedwiresinfrequencybandandtransmissiondistance,toexpandtheservicescopeoftheexchangeoffice.3SystemGeneral

ModelGHJ-2000Aintelligentdigitalmultiplexingequipmenthasanumberofvoiceanddatainterfaces,abletomeetalldemandsofusers.Ithasabuilt-inopticaltransmissionunit,andtheequipmentcostcanbegreatlyloweredbyadoptingopticaltransmissionmode.Whentheopticaltransmissionunitisnotused,theequipmenthasastandardE1interfaceforconnectionwithothertransmissiondevices.ModelGHJ-2000AintelligentdigitalmultiplexingequipmentalsohastheDIfunction,andcandistributethespeechpathsflexiblywhenaringnetworkisformed.4EquipmentFeaturesThesystemcapacityis60paths.Itsupportsdifferenttypesofuserservices.Flexibleandconvenientconfigurationofuserservicetypes.TheDIfunctionisperformedbysoftware,tomeettheneedsofdifferenttypesofusersviaflexibleconfigurationofmonitoringsystem.Differentopticalfibertransmissionsystemofthecompanycanbeconfigured.Convenientinmaintenance,andsmallvolumeenablingspacesaving.Modularframeandstructuredesign,flexibleforexpansion.Mutualhotbackupdesignbetweenpowersupplymodules.5DesignPrinciple

ModelGHJ-2000AintelligentdigitalmultiplexingequipmentconformstoITUG.703,G.704,G.706andG.715standardsandisbasedonthe30-pathgroups,eachcasecontaininguptotwosystemsof30-path,respectivelyasSystemAandSystemB.Eachsystemcontainsfourspeechpathboards,andoneachofthemfoursmallspeechpathboardscanbemounted(eachspeechpathboardhastwopathsforvoiceordata,anduserscanselectasneeded).6DesignPrinciple

ModelGHJ-2000Aintelligentdigitalmultiplexingequipmentisusuallydividedintolocalequipmentandremoteequipment.Localandremoteisdeterminedwithrespecttotraditionaltelephones.Localistheendconnectedwiththeexchangeandremoteistheendconnectedwiththeusertelephoneset.Thelocalexchangeperformsthedigitalizingprocessingfortheanaloguevoiceordigitalsignals,andconvertstheDCsignalsonthelineintoPCMfollow-upsignaling.Thetransmissionsystemmultiplexesthe2Mdigitalsignalintohighspeeddigitalsignalandsendittotheremoteuserend.Thetransmissionsystemattheremoteuserendreceivesthe2Msignal,andtheremoteequipmentthensynchronizesanddecodesthe2Msignal,sendingtheanaloguevoicesignalordigitalsignaltotheuser.7Principle

BlockDiagram

8OperationPrinciple

Monitoringcanbeperformedforbothremoteequipmentandlocalequipment.ThemonitoringinterfacesincludeoneRS485andoneRS232interface,bothprovidedbytheclockboard.Boththelocalequipmentandremoteequipmentcanbeconnectedexternallytothemastercontrolconsole,torealizerealtimemonitoringofallfunctionalboardsinthelocalequipmentcaseandremoteequipmentcaseatthelocalend.Undernormalconditions,themastercontrolconsoleisconfiguredatthelocalexchangeside.

9SystemConfiguration

InModelGHJ-2000Aintelligentdigitalmultiplexingequipment,thelocalequipmentcaseandremoteequipmentcaseareexactlytheidentical,eachcaseisconfiguredwithtwopowersupplypanels,oneringingpanel,onegrouppathpanel,8SpeechPathPanel(optionalinnumber),oneE/Msignalingpanel(optional),Thesystemconfigurationshowunder:PowersupplypanelPowersupplypanelringingpanelEMsignalingpanelSpeechPathPanel24SpeechPathPanel23SpeechPathPanel22SpeechPathPanel21SpeechPathPanel14SpeechPathPanel13SpeechPathPanel12SpeechPathPanel11grouppathpanel10SystemConfiguration

EachSpeechPathPanelhas8speechpaths,whicharedistributedon4smallspeechpathboards.Eachsmallspeechpathboardcontainstwospeechpaths(includinginterfaces).Smallspeechpathboardsofdifferenttypescanbemixedforuse.

SpeechPathPanel11~14arethespeechpathboardsofSystemA,andSpeechPathPanel21~24arethespeechpathboardsofSystemB.Amaximumof3smallspeechpathboardscanbefitonSpeechPathPanel14andSpeechPathPanel24,i.e.:amaximumof6speechpathscanbeconfigured.Forspecificarrangement,seeTable.11SystemConfigurationPathdistributiononspeechpathboardsPanel11Panel12Panel13Panel14Panel21Panel22Panel23Panel24ASystemPath1~8ASystemPath9~16ASystemPath17~24ASystemPath25~30BSystemPath1~8BSystemPath9~16BSystemPath17~24BSystemPath25~3012NetworkingMethodModelGHJ-2000Aintelligentdigitalmultiplexingequipmenthasflexiblenetworkformingability,thebasicmodesbeingpoint-to-point,starandDI.

1.Point-to-pointtelecommunicationmode:13NetworkingMethod

2.

Starnetworktelecommunicationmode：14NetworkingMethod3.DInetworktelecommunicationmode:15IntroductiontoUnits

PowersupplypanelRingingcurrentpanelGrouppathpanel：(Ordinary、Intelligent)SpeechPathPanelLocal/Remotespeechpathsubboard2/4wiretonespeechpathsubboardSynchronousdatasubboardAsynchronousdatasubboardHotlinespeechpathsubboardN*64K/V.35datapanel10MEthernetdatapanel

16Powersupplypanel

Themainfunctionsofthepowersupplypanelarevoltageconversionandsupplyingpowertothesystem.Eachequipmentcanhavetwopowersupply

panels,formutualbackup(powersupplycanbeaccomplishedwithasinglepowersupplypanel).Theinputis-48V,theoutput+5Vand-5V,andthepoweris35W.Therearethreeindicatorsonthepowersupplypanel,being-48V,+5Vand-5Vfromthetoptobottom.Theyareallgreen.Theoperationisnormalwhenindicatorsarelit,andisabnormalwhentheyarenotlit.

17

Theringingcurrentpanelprovidesringingtotheuserlines.Onthisboard,theringingmoduleworksinnon-balancedmode,i.e.,RING+isGNDandRING-is+75VAC(25Hz)ringingcurrentsignal.Theindicator(green)ontheringingcurrentpanelindicatestheoperationstatusofthepanel.Theoperationisnormalwhenitislit,andisabnormalwhenitgoesoff.Ringingcurrentpanel18Ordinarygrouppathpanel(MDX1)

Mainfunctions：l

CompletingsendingandreceivingstandardE1interfacesignalsl

PerformingtheformationanddecompositionofstandardE1signalframes.l

Generatingvarioustimesequencesignalsforreceivingandsending.l

Abletosynchronizewithexternallyinput2.048MHzclock.l

Indicatingvariousalarminformation.l

Indicatingvariousstatus.l

Monitoringcommunication,reportingthesystemstatustomastercontrolconsole,andreceivingcontrolinformationfromthemastercontrolconsole.19OrdinarygrouppathpanelOperationinstructions：

A)ForE1inputandoutputimpedance,120

balancedmodeor75

unbalancedmodecanbeselected.B)Whenitissynchronizedwithanexternalclock,theclockisofTTLlevelandisconnectedinviaacoaxialcable;thegrouppathpanelcanalsooutputa2048KHZstandardclockatTTLlevel.C)Undereachrowofindicatorsthereisadouble-rowtoggleswitch.D)

ThecommunicationwiththemastercontrolconsolecomputerE)Selectingtheclockmode.20OrdinarygrouppathpanelAlarmindicatorslamp：

Thereareatotalof16indicatorsonaordinarygrouppathpanel,theyareintworows,respectivelyindicatingSystemsAandB.Theindicatorsareasfollowsfromthetoptobottom:

AISYellowReceivingAISalarmLOSSRedReceiving2MsignalcodelossalarmFLSRedReceivingframelossofsynchronismalarmMFLSRedReceivingcompositeframelossofsynchronismalarmRAYellowOppositeendframelossofsynchronismalarmBERRedAlarmwhenlineerrorcoderate

10-3alarmRLOOPGreenRemoteend2MsignalreturnLLOOPGreenLocalend2Msignalreturn21Intelligentgrouppathpanel(MDX1_B)

Functionalblockdiagram：

Theintelligentgrouppathpanel(MDX1_B)isanordinarygrouppathpaneladdedwithtimeslotcrossconnectionunit,whichcanaccomplishblockfreecrossconnectionforfour2Mtimeslots,andthefunctionalblockdiagramisshown：

SystemAInternalreceiving(InternalreceivingA)SystemAInternalSending(InternalSendingA)SystemBInternalSending(InternalSendingB)SystemBInternalreceiving(InternalreceivingB)SystemAExternalReceiving(ExternalReceivingA)SystemAExternalSending(ExternalSendingA)SystemBExternalSending(ExternalSendingB)SystemAExternalReceiving(ExternalReceivingB)22IntelligentgrouppathpanelDesignPrinciple：

SystemAInternalSending(InternalSendingA)andSystemBInternalSending(InternalSendingB)arethe2MsignalsformedbySystemAandSystemBoftheModelGHJ-2000Aintelligentgroupdigitalmultiplexingequipment,andthetimeslotarrangementofthese2Msignalsaredeterminedbyhardware.SystemAExternalSending(ExternalSendingA)andSystemBExternalSending(ExternalSendingB)arethetwoE1signalsactuallysentbytheModelGHJ-2000AintelligentgroupdigitalmultiplexingequipmentcorrespondingtoSystemAandSystemB.

SystemAExternalReceiving(ExternalReceivingA)andSystemBExternalReceiving(ExternalReceivingB)arethetwoE1signalsactuallyreceivedbytheModelGHJ-2000AintelligentgroupdigitalmultiplexingequipmentcorrespondingtoSystemAandSystemB.SystemAInternalReceiving(InternalReceivingA)andSystemBInternalReceiving(InternalReceivingB)refertosignalssentintotheframeprocessorsofSystemAandSystemB.ThetimeslotarrangementforInternalReceivingAandInternalReceivingBsignalsisaccomplishedbythecrossconnectionunitviathemonitoringsoftware.23Intelligentgrouppathpanel

Thecrossconnectionunitcanrealizetheunblockedcrossconnectionofthe2MsignalsfromfourframesofInternalSendingA,InternalSendingB,ExternalReceivingAandExternalReceivingBtothe2MsignaltimeslotofthefourframesofExternalSendingA,ExternalSendingB,InternalReceivingAandInternalReceivingB,thisincreasingtheflexibilityofsystemoperation.ThecrossconnectionunitinModelGHJ-2000Aintelligentgroupdigitalmultiplexingequipmentaccomplishestheexchangeofatotalof120timeslotsforfour2Msignals.BecausethesignalingofPCMsystemisapath-followingsignaling,thereforethecrossconnectionunitdoesnotperformexchangeforthe16timeslots,andthesignalingexchangeisaccomplishedbytheCPUonthegrouppathpanel,andthesignalingisexchangedwiththeexchangeofspeechpathtimeslot.Therelationshipoftimeslotexchangecanbesetbythemastercontrolconsoleviathemonitoringchannel,orwithaportablecomputeronsite.24IntelligentgrouppathpanelAlarmindicatorslamp：

Thereareatotalof16indicatorsonaintelligentgrouppathpanel,theyareintworows,respectivelyindicatingSystemsAandB.Theindicatorsareasfollowsfromthetoptobottom:AISYellowReceivingAISalarmLOSSRedReceiving2MsignalcodelossalarmFLSRedReceivingframelossofsynchronismalarmMFLSRedReceivingcompositeframelossofsynchronismalarmRAYellowOppositeendframelossofsynchronismalarmBERRedAlarmwhenlineerrorcoderate

10-3alarmRLOOPGreenRemoteend2MsignalreturnLLOOPGreenLocalend2Msignalreturn25SpeechPathPanel

SpeechPathPanelconsistsofthespeechpathmasterboardandspeechpathsubboards,andthespeechpathsubboardsaremountedonthespeechpathmasterboard.Thespeechpathsubboardsaredividedintothoseforordinaryspeechpath,2/4-wiretone,64Kbpsdate,hotlinespeechpath,magnetospeechpath,etc.Eachspeechpathsubboardcontainstwospeechordatapaths.Eachspeechpathmasterboardcanbemountedwithuptofoursubboards.Mainfunctionsofspeechpathmasterboard：Generatingthetimesequencesignalsrequiredbyeachspeechpathsubboardaccordingtothetimesequencesignalgivenbythegrouppathpanel.Connectingthespeechpathsubboardandgrouppathpanelaswellaspowersupplypanel,etc.26SpeechPathPanelAlarmindicatorslamp：

Thereareeightindicators(green)onthespeechpathmasterboard,respectivelyindicatingthebusyoridlestatusofthespeechordatapathsNo.1~8fromtoptobottom.Forsubboardsofdifferentfunctions,themeaningofaOnindicatorisdifferent.SpeechpathsubboarddescriptionIndicatoronIndicatoronLocalspeechpathsubboardIndicatoroffIndicatoroffRemotespeechpathsubboardHook-offbyremoteuserHook-offbyremoteuser2-wiretonesubboardHook-onbyremoteuserHook-onbyremoteuser4-wiretonesubboardHook-offbyuserHook-offbyuserSynchronousdatasubboard(V35)Hook-onbyuserHook-onbyuserAsynchronousdatasubboardN/AN/AOrdinarymagnetosubboardNormalNormalCarrierwaveinterfacemagnetosubboardN/AN/AHotlinesubboardNormalNormal27Local/Remotespeechpathsubboard

Themainfunctionoflocalspeechpathsubboardistointerfacewiththeuserlinesoftheexchange.Itsfunctionsare:toneencodinganddecoding,ringingcurrenttesting,signalingdecoding,etc.Eachspeechpathsubboardcontainstwospeechpaths.Themainfunctionofremotespeechpathsubboardistoaccomplishtheencodingofspeechpaths,decoding,2-wire/4-wireconversion,powersupplytouser,ringing,overvoltageprotectionandtestingofuserlines,etc.Eachspeechpathsubboardcontainstwospeechpaths.

Local/Remotespeechworkingdiagram：LocalPCMRemotePCMtransmissionmedia

…………282/4-wiretonespeechpathsubboard

Themainfunctionofthe2/4-wiretonespeechpathsubboardisvoiceencodinganddecodingand2/4-wiretoneinterfacing.

2-wireinterfaceisusuallyusedforconnectionwithatoneModem.4-wireinterfaceisusuallyusedfor4-wiretoneadaptation.2/4-wiretonespeechpathsubboardsareclassifiedintoordinary2/4-wiretonespeechpathsubboardand2/4-wiretonespeechpathsubboardwithattenuator.292/4-wiretonespeechpathsubboardordinary2/4-wiretonespeechpathsubboard

：Eachordinary2/4-wiretone

speechpathsubboardcontainstwospeechpaths.2-wireInterfacelevel：2-wiresending:0dBr

0.5dBr2-wirereceiving:-3.5dBr

0.5dBr4-wireInterfacelevel:

4-wiresending:0dBr

0.5dBror+4dBr

0.5dBr4-wirereceiving:0dBr

0.5dBror+4dBr

0.5dBr302/4-wiretonespeechpathsubboard2/4-wiretonespeechpathsubboardwithattenuator：Eachofthe2/4-wiretonespeechpathsubboardwithattenuatorcontainstwo2/4-wiretoneinterfaces,andthe2/4-wireinterfacelevelcanbeadjustedbyadjustingtheattenuationvalueofattenuator.Thelevelfor4-wiresending(forsignalintoequipment)(theattenuationvalueofattenuatoris0)is-14dBr,andthemaximumlevelfor4-wiresending(forsignaloutofequipment)(theattenuationvalueofattenuatoris0)is+4dBr.Theadjustmentrangeoftheattenuationvalueofattenuatoris0dBto15.5dB,andtheadjustmentprecision0.5dB.

31Synchronousdatasubboard

Themainfunctionsofthesynchronousdatasubboardareencodinganddecodingofsynchronousdataandinterfaceadaptation.Eachdatasubboardcontainstwopathsforsynchronousdata(G.703interface)oronesynchronousdata(V.35interfaceorV.11/RS422interface).TheG.703interfacedataare64kbpssyntropicdataandV.35dataare64kbpsor128kbpssyntropicdata.Onthespeechpathmasterboard,thelocationofeachsubboardisassignedwithtwotimeslots.ForV.35subboard,thefirsttimeslotisoccupiedwhentheinterfacedatarateis64kbps,andbothtimeslotsareoccupiedwhentheinterfacedatarateis128kbps.Onthesubboardthereisatwo-positiontoggleswitch,onepositionforselectingtheinterfaceandtheotherforselectingrate.32Asynchronousdatasubboard

Themainfunctionsoftheasynchronousdatasubboardaretheconversionfromasynchronismtosynchronismandinterfaceadaptation.TheasynchronousdatasubboardprovidesinterfacesofRS-232/V.24orRS-422/V.11.Eachsubboardcontainstwointerfaces,occupyingtwovoicechannels.Themaximumrateofasynchronousdatais14.4kb/s,andcanbeuseduponplugging.

33Magnetointerfacesubboard

Themagnetointerfacesubboardprovidesamagnetointerface,forconnectionwithasinglemagnetosetormagnetoattendantconsole.Thesignalingtransmissionforthissubboardisinthedigitalsignalingmode(thesameasPCM).Thespeechpathparametersandoutgoingarethesameaswithordinaryspeechpaths.Themainfunctionsaretoneencodinganddecodingfortelephone,testingofsignal,etc.Eachspeechpathsubboardcontainstwospeechpaths.34Carrierwavemagnetointerfacesubboard

Thecarrierwavemagnetointerfacesubboardprovidesamagnetointerface,forconnectionwithasinglemagnetosetormagnetoattendantconsole.Differentfromtheordinarymagnetointerfacesubboard,thesignalingtransmissiononthissubboardisinthe2100Hzin-bandmode.Thissubboardhastheconversionfunctionbetween25Hzringingcurrentsignaland2100Hztonesignal.Foruseofthisboard,one2100Hzsignalgeneratorsubboardshouldbeused.Despiteofthenumberofcarrierwavemagnetointerfacesubboardsused,itisonlynecessarytouseone2100Hzsignalgeneratorsubboardineachcase.35Hotlinespeechpathsubboard

Themainfunctionsofthehotlinespeechpathsubboardarehotlinetelephonetoneencodinganddecoding,hook-offandhook-ontesting,feedingtotelephonesetandringing.Eachspeechpathsubboardcontainstwospeechpaths.36N*64K/V.35databoard

TherateoftheinterfaceisN*64Kb/s(N=1~30),itcanprovidetwodatainterfacesofV.35(orV.11).ThespeechtimeslotofoccupiedPCMcanbeset,andDTEandDCEmodecanalsobeselected.

K8：Firstdatainterfacehasselectedthespeechpathtimeslotsofpaths1~10.K9：Firstdatainterfacehasselectedthespeechpathtimeslotsofpaths11~20.K10：Firstdatainterfacehasselectedthespeechpathtimeslotsofpaths21~30.K3：Seconddatainterfacehasselectedthespeechpathtimeslotsofpaths1~10.K2：Seconddatainterfacehasselectedthespeechpathtimeslotsofpaths11~20.K1：Seconddatainterfacehasselectedthespeechpathtimeslotsofpaths21~30.37N*64K/V.35databoard

Alarmindicatorslamp：N*64k/V.35databoardhas6indicatorsonthefront,numbered1~6fromtoptobottom.Thereisaredindicatorinthepanel.Themeaningofeachindicatorisasshown.No.IndicatorcolorMeaning1GreenThereissendingdataindatapathNo.1whenON2GreenThereisreceivingdataindatapathNo.1whenON3GreenThereissendingdataindatapathNo.2whenON4GreenThereisreceivingdataindatapathNo.2whenON5YellowDatainthefirstpathinloop-backmode(K4[1]ON)6YellowDatainthesecondpathinloop-backmode(K4[2]ON)InsidepanelRedConflictinginthesettingofoccupiedtimeslotsfortwodatapathswhenON3810MEthernetdatapanel

InModelGHJ-2000Aintelligentdigitalmultiplexingequipment,the10BASE-TinterfaceisusuallyforinterconnectionofEthernet,andoneE1transmissionchannelcanrealizethesimultaneousconnectionofvoice,lowspeedasynchronousdata,mediumspeedsynchronousdataandEthernetdata.Intheactualapplication,theEthernetofmanycomputersissmall,andtheyneedtobeconnectedwiththeEthernetofthehigherleveloratthesamelevel,andtheuseofitsownorrented2Mlineasthetransmissionchannelwouldbeacomparativelyconvenientchoice.Thus,whenthetwoEthernetsrequiringtobeconnectedneedtoconnectseveralpathsofvoiceorlowspeeddata,byusinga10Base-TontheEthernetHUBandviatheModelGHJ-2000Aintelligentgroupdigitalmultiplexingequipment,interconnectionbetweenEthernetandvoicechannelcanberealizedveryconvenientlyandquicklythrougha2Mchannel,whichcanbeopticalfibercableormicrowave.3910MEthernetdatapanelTypicalApplication：

Thesizeofa10BASE-TdatapanelisthesameasaSpeechPathPanel,anditcanbepluggedintoanypositionofSpeechPathPanel11~SpeechPathPanel14(whenusedinSystemA)orSpeechPathPanel21~SpeechPathPanel24(whenusedinSystemB)ofSystemAorSystemB.typicalapplicationshowasfollows.4010MEthernetdatapanelSelectionofoperationmode：

ThenumberoftimeslotsoccupiedintheE1signalframebytheEthernethighspeeddataduringtransmissionisdeterminedbythesettingofthetoggleswitchonthepanel.10BASE-Tdatainterfacepanelhastwotoggleswitches,K2andK3,forselectingtheoperationmodeof10BASE-Tinterface.Theyaresetasfollows:K2—1：duplexmodeselection:ONforfullduplexandOFFforsemi-duplex.K2—2：packagefilteringselection:ONfornopackagefilteringandOFFforpackage

filtering.K3—1：compressionselection:ONforpackagecompressionandOFFfornopackagecompression.4110MEthernetdatapanel

Indicators：

10BASE-Tdatainterfacepanelhastwoindicatorsonthefront,andthegreenoneistheLANinterfaceindicator,whichisONwhentheEthernetportisconnectednormally,andflasheswhenthereisadataflow.Theyellowindicatorbelowistheconflictingindicator,whichisONwhenthereisconflictattheEthernetport;frequentconflictsindicateabnormalofcircuitoperation,andthesettingofnetworkscanbecheckedformatching.Excessivehighloadonthenetworkmayalsoleadtofrequentconflicts.Inthiscase,somedatasourcescanbeturnedofftolowerthenetworkloaddataflow,orthetransmissionbandwidthcanbeincreased.42Installation

ModelGHJ-2000Aintelligentdigitalmultiplexingequipmentlocalequipmentandremoteequipmentusetheidentical19-inchwidemetalcases,whichareincompactstructureandcanbeusedforfixingallfunctionalunitboards.

Themasterboardsincasesareexactlythesameforbothlocalequipmentandremoteequipment,toprovidesignalinterconnectionforallfunctionalboards,2Mcodeflowinputandoutput,powersupplyinput,alarmoutputandinterfacingwiththeRS232interfaceofmastercontrolconsole.TheconnectionbetweentheDF’sandthisequipmentisalsowireddirectlyfromthemasterboards.

Forinstallation,firstplacetheframeatthedesignatedlocation(conduit),andconnectthegroundingwireoftheframefirmlyandreliablywiththeground.Onthelocalsideequipment,thegroundingwireoftheframemustbefirmlyandreliablyconnectedwiththegroundbeforeinstallingthecase(Thegroundingfortheprogrammableexchangeshouldalsobeconnectedwiththegroundingofthelocalexchangeframewithaspecialconductor).

43InstallationGHJ-2000AGHJ-2000AEquipmentSchematicofcase

44structure

GHJ-2000AEquipmentSchematicofmasterboardcardpositions

45ConnectingPowerSupply：

Thetwo2-pinsocketsattheundersiderightcornerofthemasterboardandthe2-pinconnectorsunderthemareforexternalpowersupplyfortheequipment,theupperpinbeingpowerinput(normally–48V)andthelowerpinbeingpowergrounding(theindicatinglettersonthemasterboardcanbereferencedwhenmakingtheconnection).Withthepowersupplycordprovidedwiththeequipment,theblue(orblack)leadshouldbeconnectedtothepowersupplyandtheredleadtothesupplyground.－48VGND46Connecting2Msignallines

：

Thefourcoaxialsocketsatthelefttopcornerofthemasterboardareforinputandoutputofthe2Msignal.Tx2M1istheoutputofSystemA2Msignal,Rx2M1istheinputforSystemA2Msignal,Tx2M2istheoutputforSystemB2Msignal,andRx2M2istheinputforSystemB2Msignal.Whentheinterfaceisin120Ωbalancedmode,thecoaxialsocketsarechangedtothreepins,andthesignalconnectionismadeinwindingmode(Themiddleandlowerpinsaresignallines,andthetoppinforgroundingline).unbalancedmodeTx2M1Rx2M1Tx2M2Rx2M2balancedmodeTx2M1Rx2M1Tx2M2Rx2M247ConnectingAlarmline：

Thetwo2-pinsocketsattheupperleftcornerofthemasterboardareforconnectionlinesofsystemalarmandframetopalarmbox.Thetwosocketsareparallel,oneforconnectingthetopalarmbox,a