Simrad SU90 - Grounding; Physical Protection

AppendixDBasiccablerequirements
Itisimportantthatcables,otherthanthosesupplyingservicestotheequipmentinstalled
inaradioroom,arenotinstalledthrougharadioroom,highpowerswitchgearorother
potentialsourcesofinterference.Cableswhichmustpassthrougharadioroommust
bescreenedbyacontinuousmetalconduitortrunkingwhichmustbebondedtothe
screeningoftheradioroomatitspointsofentryandexit.
Physicalprotection
Cablesexposedtotheriskofphysicaldamagemustbeenclosedinasteelconduit
orprotectedbyametalcasingunlessthecable'scovering(e.g.armourorsheath)is
sufcienttoprotectitfromthedamagerisk.
Cablesexposedtoanexceptionalriskofmechanicaldamage(forexampleinholds,
storage-spacesandcargo-spaces)mustbeprotectedbyasuitablecasingorconduit,
evenwhenarmoured,ifthecablecoveringdoesnotguaranteesufcientprotection
forthecables.
Metallicmaterialsusedforthephysicalprotectionofcablesmustbesuitablyprotected
againstcorrosion.
Grounding
Allmetalliccablecoverings(armour,metallicsheathingetc.)mustbeelectrically
connectedtothevessel'shullatbothendsexceptinthecaseofnalsub-circuitswhere
theyshouldbeconnectedatthesupplyendonly.
Groundingconnectionsshouldbemadeusingaconductorwhichhasacross-sectional
areaappropriateforthecurrentratingofthecable,orwithametalclampwhichgrips
themetalliccoveringofthecableandisbondedtothehullofthevessel.Thesecable
coveringsmayalsobegroundedbymeansofglandsspeciallyintendedforthispurpose
anddesignedtoensureagoodgroundconnection.Theglandsusedmustbermly
attachedto,andingoodelectricalcontactwith,ametalstructuregroundedinaccordance
withtheserecommendations.
Electricalcontinuitymustbeensuredalongtheentirelengthofallcablecoverings,
particularlyatjointsandsplices.Innocaseshouldtheshieldingofcablesbeusedasthe
onlymeansofgroundingcablesorunits.
Metalliccasings,pipesandconduitsmustbegrounded,andwhenttedwithjointsthese
mustbemechanicallyandelectricallygroundedlocally.
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