Simrad ST90 - Page 260

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442703/B
Note
OntheST94HullUnit,thetransducerisautomaticallyhoistedto1.6metreswhenvessel
speedexceeds11knots.
Thehullunitisalargemechanicalconstruction.Itismountedonthetopofthe
installationtrunk.Theinstallationtrunkpenetratestheship’shull,andallowsthe
transducertobeloweredintothesea.Thehullunitisnormallylocatedintheforward
partofthevessel.Thislocationisrecommendedtoavoidthenoisefromthepropellers
andtheengine.
ThepurposeoftheMotorControlUnitistocontrolthehoistingmotoronthehullunit.
WhenyoumaketheappropriatecommandsontheST90sonar,theMotorControlUnit
willstartandstopthemotor.Itwillalsomakesurethatthemotorrotatesthecorrectway.
Themotionsensorforthebuilt-inelectronicstabilizationofthesonarbeamsisprovided.
•Tolowerthetransducer,pressDownontheOperatingPanel.Toindicatetransducer
movement,theDownindicatorlampashes,andanaudiblesignalissounded.When
thebottompositionhasbeenreached,theindicatorlampislit,andtheaudiblesignal
stops.
•Toretractthetransducer,pressUpontheOperatingPanel.
Thetransducercanalsobeloweredtoanyselectedmiddleposition.OntheOperating
Panel,pressMiddle.Incaseofpowerfailure,thetransducercanberaisedorlowered
manuallybymeansofahandcrank.
Note
IfyouforgettohoistthetransducerbeforetheST90isswitchedoff,thetransduceris
hoistedautomaticallybeforethepowerisdisconnected.Thetransducerisalsohoisted
automaticallyifaseriousmalfunctionoccurstothecommunicationbetweenthebridge
andthehullunit.
Caution
Ifthetransducerhitslargerobjectsorbottom,thetransducershaftmaybebent,or
-inworstcase-itcanbebrokenoff.Abrokentransducershaftwillcausewater
leakagethroughthetopoftheshaft.Ifyoususpectthatthetransducershaftisseriously
damagedwithholes,donot
retractthetransducertoitsupperposition.
Topreventseriousdamagetothevesselorthevesselstability,youmusthaveawater
pumpandawarningsysteminthesonarroom.
SimradST90InstallationManual