Simrad ST90 - Page 139

442703/B
137
Context
Asageneralrecommendation,the
hullunitshallbeorientedwiththe
hoist/lowermotorpointingaft.Ifthis
orientationmakesitdifculttoaccess
theMotorControlUnit,thehullunit
mayberotatedduringitsinstallation
tothemostsuitabledirection.
Thehullunit,transducerand
transducercablemustbehandled
withcare.
Note
•Thetransducerisprotectedwith
athicklayeroffoamtoprevent
damageduringtransportandhull
unitinstallation.Thisprotection
mustremainattachedwhilethehullunitisbeingmanoeuvredintothesonarroom.
•Thetransduceriscoveredwithathickredprotectivecoatingmadeofaspecial
plastictype.Theredprotectivecoatingisanvitalpartofthetransducer.Itisvery
importantthatneitherthiscoatingnortheinternalpartsofthetransducerare
damagedduringthehandling,installationorcleaning.Anyholesand/orscratchesin
thetransducersurfacewillallowwatertopenetratethetransducer.Ifaleakoccurs,
thetransducermustbereplaced.
•Thetopmatingsurfaceoftheinstallationtrunkmustbeprotectedwithablindange
orwoodencoveratalltimesuntilthehullunitisinstalled.Itisveryimportantthat
thissurfaceiscleanandundamaged,becauseitmustbewatertightafterthehullunit
hasbeeninstalledontopoftheinstallationtrunk.
•TheMotorControlUnitmustneverbephysicallydismountedfromthehullunitgantry.
AdedicatedO-ringisprovidedwiththeST90delivery.ThisO-ringensuresawatertight
connectionbetweentheinstallationtrunkandthebottomofthetransducershaftsleeve.
Duringtheinstallationprocess,makesurethatthisO-ringiskeptsafefromdamage,and
thatthetopoftheinstallationtrunkiskeptclean,smoothandwithoutphysicaldamage
suchasscratchesordents.ProperO-ringlubricationmustbeappliedbeforethehullunit
ismountedontopoftheinstallationtrunk.
Procedure
1LifttheHullUnit(withthetransducerprotectionstillinplace!)andplaceit
verticallyovertheinstallationtrunk.
Whilelifting,makesurethatyoudonotdamagethedelicatepartsofthehullunit.
Installingthehullunit