Specifications

Section-2 Installation
October 17, 2013
2‐4
Copyright©2013,HarrisBroadcast
WARNING:Disconnectprimarypower priortoservicing. 888‐2693‐004
Ifusingmetalconduit,installtheACmainswiringinaseparateconduitfromallLPUinputcablesandsmallsignal
lines.
Ifapr
e‐wiredrackisnotordered,matingconnectors(IEC15andIECC20)areprovidedwiththetransmitter
shipmenttoallowterminationofACmainscablesfromtheACmainsdistributionpanel.Iftheseconnectorscan’tbe
locatedpleasecontactHarrisCustomerService.
2.6.1 SurgeSuppressionDevices
HarrisstronglyrecommendstheuseofsurgeprotectiondevicesontheincomingACmainslines.Thesedevices
protectagainstdamagesduetotransientsarisingfrombothnaturalandman‐madesources.(e.g.lightningand
inductiveloadswitching).Clearpreferenceistobegivento"series"typesurgeprotectiondevices‐‐featuring
protectionbybothaserie
sinductance/shuntcapacitorfi lterandshuntthresholddevice‐‐oversimpleshunt‐only
clampingdevices.Thesurgeprotectormustbesizedtohandlethefullamperageofthe loaditisprotecting(plusa
nominalsafetymargin)andbeconnectedtothebuildinggroundsystembyshort,di
rectconnections.Inthecase
wheretheshuntprotectionelementsareprotectedbyafuse,itisnecessarytoperiodicallychecktheintegrityofthe
fusetoensurecontinuedtransientprotection.
Thet
ransmitterandthepowersuppliesmoduleshavebeentestedtospecEN61000‐4,whichguaranteesa
protectionagainst2kVtransients.However,thisprotectionhasitslimits,anditis prudenttoprotectyour
investmentbyinstallingqualitysurgesuppressionequipment.
Caution
.FAILURE TO FOLLOW THESE RECOMMENDATIONS MAY LEAD TO
SHORTENED EQUIPMENT LIFE AND REDUCED RELIABILITY.
2.7 GroundRequirements
TwoseparategroundconnectionsarerequiredfortheUAXtransmitter:anACsafetygroundandanRFearth
ground.
TheACsaf
etygroundpreventsanelectrocutionhazardshouldadangerouspotentialfrominsidetheunit
accidentallycontactthemetalchassis.TheACsafetygroundworksbyprovidingasecure,uninterruptedpathforany
waywardelectricalcurrenttoreturntothesource:thesecondarywindingofthelocalpower‐gridtransformer(o
r
generator).Thisensuresthatanyexposedmetalpartswillnotsimply“float”toavoltageleveldangeroustohumans
inthecaseofanaccidentalcontactwithmainsvoltageandthatasufficientfaultcurrentwillbedrawntotripany
circuitprotectiondevices.
TheACsaf
etygroundconnectionismadeautomaticallyfortheLPUandPABchassisviathegreen/yellowwire(third
prong)oftheACinputcord.
Inthecas
eofaHarris‐suppliedACdistributionchassis,thegreen/yellowphysicalearth(PE)connectionfromthe
incomingACmainsserviceterminatesatthePEterminaloftheACdistributionchassis.Theindividualsubassemblies
makingupthetransmitterconnectviathegreen/yellowwireoftheirmainscordstothesamePEte
rminalontheAC
distributionchassis.Whenpresent,therackbuss‐barwillalsoconnecttothisPEterminal.
TheACsaf
etyground(green/yellow)wirefromthetransmitterrackshouldterminateatasuitablephysicalearth
(PE)or(PEN)connectionattheACmainsentrance/distributionpanel,orasotherwisedictatedbysafetynorms.In
thosesystemswithonlyadirectearthgroundinsteadofawiredPEconnectionbacktothepo
wersource,theuseof
specialground‐faultsensingcircuitprotectiondevicesisindicated.
Ina
dditiontotheequipmentchassis,allmetalenclosuresandconduitpiecespotentiallyexposedtomainsvoltages
inthecaseofafaultshouldhaveasecure,uninterrupted,conductivepathbacktothePEterminalinthemains
entrance.
TheRFea
rthgroundpreventsdamagetotheequipmentduringlightninginducedtransientsbyprovidingalow
impedancepathforlightningtoreturntotheearth.AnRFgroundstrap/wireattachmentpointislocatedattherear
oftheLPUandPABchassis.Thisconnectionissuitableforuseinasinglepoi
ntgroundingsystem,withtheground
strapattachedtotheequipmentrackandthe rack,inturn,toacommongroundingplate.Astrapwithaminimum
widthof5cmshouldbeusedtoconnecttheequipmentracktothe buildingearthgroundsystem.