Installation manual

AppendixCBasiccablerequirements

APPENDIXC—BASICCABLEREQUIREMENTS

Thischapterprovidesgeneralinformationrelatedtotheinstallationofsystemcables.

Topics

•Cabletraysonpage37

•RadioFrequencyinterferenceonpage38

•Physicalprotectiononpage38

•Groundingonpage38

•Cableconnectionsonpage39

•Cableterminationsonpage39

•Cableidenticationonpage39

Cabletrays

Allpermanentlyinstalledcablesassociatedwiththesystemmustbesupportedand

protectedalongtheirentirelengthsusingconduitsand/orcabletrays.Theonlyexception

tothisruleisoverthenalshortdistance(maximum.0,5meters)asthecablesruninto

thecabinets/unitstowhichtheyareconnected.Theseshortserviceloopsaretoallowthe

cabinetstomoveontheirshockmounts,andtoallowmaintenanceandrepair.

•Whereverpossible,cabletraysmustbestraight,accessibleandplacedsoastoavoid

possiblecontaminationbycondensationanddrippingliquids(oil,etc.).Theymustbe

installedawayfromsourcesofheat,andmustbeprotectedagainstphysicaldamage.

Suitableshieldsmustbeprovidedwherecablesareinstalledinthevicinityofheat

sources.

•Unlessitisabsolutelyunavoidable,cablesshouldnotbeinstalledacrossthevessel’s

expansionjoints.Ifthesituationisunavoidable,aloopofcablehavingalength

proportionaltothepossibleexpansionofthejointmustbeprovided.Theminimum

internalradiusoftheloopmustbeatleasttwelvetimestheexternaldiameterof

thecable.

•Whereaservicerequiresduplicatesupplylines,thecablesmustfollowseparatepaths

throughthevesselwheneverpossible.

•Signalcablesmustnotbeinstalledinthesamecabletrayorconduitashigh-power

cables.

•Cablescontaininginsulationmaterialswithdifferentmaximum-ratedconductor

temperaturesshouldnotbebunchedtogether(thatis,inacommonclip,gland,conduit

orduct).Whenthisisimpractical,thecablesmustbecarefullyarrangedsuchthatthe

maximumtemperatureexpectedinanycableinthegroupiswithinthespecications

ofthelowest-ratedcable.

•Cableswithprotectivecoveringswhichmaydamageothercablesshouldnotbe

groupedwithothercables.

•Cableshavingacoppersheathorbraidingmustbeinstalledinsuchawaythat

galvaniccorrosionbycontactwithothermetalsisprevented.

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