Simrad SU90 - Page 38

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409977/B
TheSU90operateswith384individualchannelshandledby12transceiverboards.
Ifasinglechannelfailsduringnormaloperation,youarenotlikelytodetectit.
Evenifseveralchannelsfail,youmaynotseeit.
Thedetectionofafaultychanneldependsonthephysicallocationoftherelevant
transducerelement.Iffaultychannelsaregroupedtogetheronthetransducerface,
thismaycauseavisibledefectintheSU90presentation.Iftheyarescattered,
thevisibledefectmaybealothardertosee.Inallcases,theechoesfromthe
neighbouringchannelscauseaninterpolationthatwillrestorealotofthedegraded
presentation.
Note
Forfurtherinvestigationsofthisissue,usethefunctionalityofferedbytheElement
BITE(ElementBuiltInTestEquipment)dialogbox.
10Iftheresultfromthereceptiontestshowsanumberoftransducerelementsthatare
eitherdefectiveorofferreducedperformance,repeatthetest.
Withthevesselinport,theenvironmentalconditionsarenotsatisfactory.Inthe
shallowwatersoftheport,noisefromothervessels,dockyardworkersormachinery
willcauseunreliabletestresults.Ifyoudothistestsinabusyharbour,orwithnoise
sourcespresent,thesensitivereceiverswilldetectallthenoiseinthenearbywaters.
Excessivenoiseorinterferencemaybemisinterpretedasphysicaldefects.
Youmayneedtorepeatthetestseveraltimes,and-ifnecessary-implementa
"silentship"toimprovetheconditions.
11Finishthetest.
aClosetheBITE(BuiltInTestEquipment)dialogbox.
bSetTxPowertoOff.
cHoistthetransducerbackuptoitsupperposition.
Result
Requirements
Results
Themaximumnumberofunserviceableelementsis4.
Dateandsignature:
Furtherrequirements
Ifthenoiselevelishigherthanspecied,youmustcheckthereason(s)forthis.
•CheckthegroundingoftheTransceiverUnit.
•Verifythatotherelectricequipmentand/ormachineryonboard,suchascooling
systems,hydraulicpumps,electricmotorsetc,donotinuenceonthenoisereading.
Switchoffasmuchmachineryaspossible,especiallyelectricalmotors.
•Checkforinterferencefromotherhydroacousticsystems.
SimradSU90HarbourAcceptanceTest