Raymarine VCM100 - Page 31

•Surroundinglargeobjects,inthesamehorizontalplane,can
interferewiththeradarsignalandcauseblindareasorshadow
sectorsandfalsetargetsontheradardisplay(seebelow).
Donotmounttheradarscannersohighthatitisaffectedbythe
pitchingandrollingofthevessel.
Shadowareasandfalseechoes
Mounttheradarscannerawayfromlargestructuresorequipment,
suchasenginestacks,searchlights,horns,ormasts.Theseobjects
maycauseshadowareasandfalseechoes.Forexample,ifyou
mounttheradarscanneronamast,echoesfromothertargetsmay
bereectedfromthemast.Wetsailsmayalsocauseshadowareas,
soradarperformancemaybereducedintherain.Itisparticularly
importanttoavoidshadowareasnearthebow.Raisingoreven
loweringtheradarscannermayhelptoreducetheseeffects.
Inshadowareasbeyondtheobstructiontherewillbeareductionof
thebeamintensity.Theremaybeablindsectorifthebeamintensity
isnotsufcienttoobtainanechofromanobject.Thismayoccur
evenatcloserange.Forthisreasontheangularwidthandrelative
bearingofanyshadowareamustbedeterminedatinstallation.
Youmaybeabletodetectshadowareasorfalseechoesonyour
multifunctiondisplay.Forexample,seacluttercanbeusedasa
goodindicatorofblindarcs.Darksectorsontheradardisplay
indicatepossibleshadowedareas.Thisinformationshouldbe
postednearthedisplayunitandoperatorsmustbealertfortargets
intheseblindareas.
Access
Theradarscannershouldbeeasilyaccessibletoallowmaintenance
tobecarriedoutsafely.Sufcientclearancemustbeallowedtofully
openthescannerunitformaintenanceandservice.
Mountingplatform
Theradarscannermustbemountedonarigidandstableplatform.
Theplatformmustbecapableofsupportingthemassandinertia
oftheradarscannerunderseagoingconditions.Theplatform
shouldnottwist(causingbearingerrors)orbesubjecttoexcessive
vibration.
Themountingsitemustbeclearofthefollowing:
•Ropes.
•Movingrigging.
•Heat.
•Fumes.
•People.
Magneticcompass
Mounttheradarscanneratleast1mawayfromamagnetic
compass.
Multipleradarscanners
Iftworadarscannersareinstalledatdifferentlocationsinadual
radarsystem,careshouldbetakentoallowforthedifferencein
positionoftheradarswhenswitchingbetweenthetwoonyour
multifunctiondisplay.Thisisespeciallynoticeableatshortranges
onlargervessels.
Cables
•Allcablesshouldbeadequatelyclampedandprotectedfrom
physicaldamageandexposuretoheat.Avoidrunningcables
throughbilgesordoorways,orclosetomovingorhotobjects.
•Whereacablepassesthroughanexposedbulkheadordeckhead,
useawatertightfeed-through.
Locationandmounting
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