Simrad EK80 - Radio Frequency Interference; Physical Protection of Cables

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5Cablescontaininginsulationmaterialswithdifferentmaximum-ratedconductor
temperaturesshouldnotbebunchedtogether(thatis,inacommonclip,gland,conduit
orduct).Whenthisisimpractical,thecablesmustbecarefullyarrangedsuchthatthe
maximumtemperatureexpectedinanycableinthegroupiswithinthespecicationsof
thelowest-ratedcable.
6Cableswithprotectivecoveringswhichmaydamageothercablesshouldnotbe
groupedwithothercables.
7Cableshavingacoppersheathorbraidingmustbeinstalledinsuchawaythatgalvanic
corrosionbycontactwithothermetalsisprevented.
8Toallowforfutureexpansionofthesystem,allcablesshouldbeallocatedspare
conductorpairs.Also,spacewithinthevesselshouldbesetasidefortheinstallationof
extracables.
Radiofrequencyinterference
Allcablesthataretobepermanentlyinstalledwithin9m(30ft)ofanysourceofRadio
Frequency(RF)interferencesuchasatransmitteraerialsystemorradiotransmitters,must,
unlessshieldedbyametaldeckorbulkhead,beadequatelyscreened
Suitablescreeningcanbeestablishedusingsheathing,braidingorothersuitablematerial.In
suchasituationexiblecablesshouldbescreenedwhereverpossible.
Itisimportantthatcables,otherthanthosesupplyingservicestotheequipmentinstalled
inaradioroom,arenotinstalledthrougharadioroom,highpowerswitchgearorother
potentialsourcesofinterference.Cableswhichmustpassthrougharadioroommustbe
screenedbyacontinuousmetalconduitwhichmustbebondedtothescreeningoftheradio
roomatitspointsofentryandexit.
Physicalprotectionofcables
Cablesexposedtotheriskofphysicaldamagemustbeenclosedinasteelconduitor
protectedbyametalcasingunlessthecable'scovering(forexamplearmourorsheath)is
sufcienttoprotectitfromthedamagerisk.
Cablesexposedtoanexceptionalriskofmechanicaldamage(forexampleinholds,
storage-spacesandcargo-spaces)mustbeprotectedbyasuitablecasingorconduit,even
whenarmoured,ifthecablecoveringdoesnotguaranteesufcientprotectionforthecables.
Metallicmaterialsusedforthephysicalprotectionofcablesmustbesuitablyprotected
againstcorrosion.
Cablelayoutandinterconnections