Installation manual
SimradES70/PI50MarineComputer
•Toallowforfutureexpansionofthesystem,allcablesshouldbeallocatedspare
conductorpairs.Also,spacewithinthevesselshouldbesetasidefortheinstallation
ofextracables.
RadioFrequencyinterference
Allcablesthataretobepermanentlyinstalledwithin9m(30ft)ofanysourceofRadio
Frequency(RF)interferencesuchasatransmitteraerialsystemorradiotransmitters,
must,unlessshieldedbyametaldeckorbulkhead,beadequatelyscreenedbysheathing,
braidingorothersuitablematerial.Insuchasituationexiblecablesshouldbescreened
whereverpossible.
Itisimportantthatcables,otherthanthosesupplyingservicestotheequipmentinstalled
inaradioroom,arenotinstalledthrougharadioroom,highpowerswitchgearorother
potentialsourcesofinterference.Cableswhichmustpassthrougharadioroommust
bescreenedbyacontinuousmetalconduitortrunkingwhichmustbebondedtothe
screeningoftheradioroomatitspointsofentryandexit.
Physicalprotection
Cablesexposedtotheriskofphysicaldamagemustbeenclosedinasteelconduit
orprotectedbyametalcasingunlessthecable’scovering(e.g.armourorsheath)is
sufcienttoprotectitfromthedamagerisk.
Cablesexposedtoanexceptionalriskofmechanicaldamage(forexampleinholds,
storage-spacesandcargo-spaces)mustbeprotectedbyasuitablecasingorconduit,
evenwhenarmoured,ifthecablecoveringdoesnotguaranteesufcientprotection
forthecables.
Metallicmaterialsusedforthephysicalprotectionofcablesmustbesuitablyprotected
againstcorrosion.
Grounding
Allmetalliccablecoverings(armour,metallicsheathingetc.)mustbeelectrically
connectedtothevessel’shullatbothendsexceptinthecaseofnalsub-circuitswhere
theyshouldbeconnectedatthesupplyendonly.
Groundingconnectionsshouldbemadeusingaconductorwhichhasacross-sectional
areaappropriateforthecurrentratingofthecable,orwithametalclampwhichgrips
themetalliccoveringofthecableandisbondedtothehullofthevessel.Thesecable
coveringsmayalsobegroundedbymeansofglandsspeciallyintendedforthispurpose
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