Specifications

Section-4 Theory
November 11, 2013
4‐2
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4.3 ACDistribution
ThreephaseACmainsmustbesuppliedtothePAcabinetsviacircuitbreakerCB23andCB24ontheACmainsinput
assembly(A15).Thetransmittercanaccept208‐240VAC(DeltaorWYE)or380‐415VAC(WYE)bychangingjumpers
orconnectionsinfourareas:
• TerminalboardsTB1andTB2areintheACdistributionpanel.TheTB1andTB2JumpersaredescribedinSec‐
tion2.8.3,CheckingACConfiguration,onpage2‐13.
• Para llelMOVboards(A15A1&A15A2).MOVboardjumpersareshownonsheet8ofthePACabinetMain
WiringDiagram,drawingnumber843‐5601‐001.
• DriverandPAbackplaneboards.OntheIPAandPAbackplaneboards,drawingnumbers801‐0222‐131and
801‐0222‐101respectively,thejumpersonTB1,TB2,andTB3areconnectedbetweenterminals2and3for
208to240VACDeltaorWYEandconnectedbetweenterminals1and2
for380to415VACWYEconnections.
• Aneutralconnectionisrequired,fromtheACserviceentrancetoCB23andCB24(ifused)forthe380to415
voltWYEconnection,butnoneutralconnectionisrequiredforthe208to240voltDeltaorWYEconnections.
440to480VACDeltaorWYEconnectionsrequireastep
downtransformer.
Ifproperlyjumperedtherewillbethreephase208‐240VACappliedtoeachdriverandPAmodule.
4.4 TransmitterControlSystem
TheMaxivaULXSeriestransmittersutilizeaveryadvancedbutsimpletousecontrolsystem.Thefullyoutfitted,
singlecabinet,liquid‐cooledtransmitterconsistsof1poweramplifiercontrolcabinet,2preamplifiers,2IPAs
(drivers),16PA(poweramplifier)modules,aTCU(transmittercontrolunit),oneortwoM2Xexcitersand
acooling
systemthatincludesinterconnectingplumbing,pumpmodule,and heatexchanger(cooler)unit.
Inordertoreducecostandsimplifythedesign,theamplifiersand IPA(driver)modulesdonotcontainmicro
controllers.ACPLD(complexprogrammable logicdevice)basedmonitorboardineachPAandIPAisresponsiblefor
reportingfaultsbacktotheTCUandtakingactionwhentheON/STBYcommandis
issuedfromtheTCU.
Inmulti‐cabinetsystems,thereisaTCUineachcabinetandthemaincabinet(no.1)TCUcontainsaGUI(graphical
userinterface)screenandassumestheroleofthemastercontrollerforthesystem.TheTCUsintheotherPA
cabinetsareconsideredslaves;theydon’thaveGUIscreens
anddonotrequireallofthecardsusedinthemain
cabinetTCU.ForadditionalinformationontheTCUandthevariousboardsthatitcontainssee
1.2.3onpage1‐5.
TheTCUsineachcabinetcontainanMCM(mastercontrolmodule)module.TheMCMmodulesineachTCUare
connectedbythesystembus.ThesystembusoriginatesinthemaincabinetTCUandconnectstotheMCMcardsin
allotherTCUs.
TheTCUineachcabinetusesthecabinetbus,DriveAandBbusses,andBP1throughBP4bussesforcontroland
communicationswithineachcabinet.ThesebusestietheMCMandtwoPAInterfaceboards(intheTCU)toallofthe
RFamplifiersinthecabinet.The
useofseparatesystemandcabinetbusallowseachcabinettooperate
independentlyincaseacabinetfails.
4.4.1 GraphicalUserInterface(GUI)
TheGUIisatouchscreen,panelPCwhichincludes5.25"color,1/4VGAdisplay.Thisistheprimarylocalinterfacefor
theoperatorbutisnotrequiredtooperatethetransmitter.Theprimaryoperatorcontrols,ON,OFF,RAISE,LOWER
arelocatedonthefrontpanelnexttotheGUI.Operationand
navigationoftheGUIiscoveredinSection3ofthis
manual.TheGUIscreenispresentonlyinthemainTCU(cabinet1inmulticabinetsystems).
4.4.2 TransmitterRFPowerControl
TheIPAandPAmoduleshavenogainadjustment.ThetransmitterRFoutputpoweriscontrolledviathephaseand
gainboardlocatedinthepredrivermodules.Thepredriversaretheonlycomponentsinthedrivechain(besidesthe
exciter)capableofadjustingtheirRFpowerbasedonacommandfrom
theMCM.