Installation manual

SimradES38-12
Example:Acousticwindow
Figure11Acousticwindow
ASteeltank
BOil
CAcousticwindow
DCableserviceloop
EStufngtube
FCableinsteelconduit
GOilinlet
Thetransducershowninthegureis
mountedinsidethetankbehindastrong
acousticwindow.
Thewindowistypicallymadeof
polycarbonate.Thetankislledwithoil.
Transducermountedinsidethehull
Thetransducercanalsobemountedinsidethehull.
Aninstallationofthetransducerinsidethehull,andsoundingthroughthehull,requiresa
goodacousticcontactbetweenthetransducerfaceandthehull.Buildatankaroundthe
transducerandllitwithaliquid.Oilusedinhydraulicsystemsisawellsuitedliquid
forthispurpose.Itcontainsnogasbubblesandisnon-corrosive.
Typicalvaluesofthetwowaylossare3dBforpolyester,6dBforaluminiumand10dB
forsteel.Hullsmadeofwoodorasandwichtypewithfoaminthemiddle,attenuate
thesoundsomuchthatthroughhullsoundingmustberegardedasimpossible.Theloss
varieswiththedistancebetweentransducerfaceandthehull.Thebestresultisobtained
whenthedistanceishalfawavelength.ConsultSimradforadvice.Inadditiontothe
loss,thebeampatternisdegraded,becausealargerareaofthehullissetintovibrations.
Usemountingplatewheneverprovided
Certaintransducersmaybeprovidedwithamountingplate,orwithdrawingstoallow
forlocalproductionofthis.
Themountingplateisweldedtotheholepreparedforthetransducer.Boltsthroughthe
transducerbodyintothemountingplatewillsecurethetransducer.
Smoothsurfaceisimportant
Mountingscrewsorboltsmustnotbeextrudingfromthetransducerorthearea
immediatelyaroundit.
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