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394149/C
Makinganoise/speedcurvetodeterminevesselnoise
TheperformanceoftheEK80Widebandscienticechosounderwillalwaysbelimitedby
differentnoisesources.Duringtheseaacceptancetest,accuratenoisemeasurementsmust
beperformedfordifferentvesselspeeds.Theweatherandseaconditionsforthenoise
measurementswillbethoseatthetimeoftheseaacceptancetest.
Prerequisites
TheEK80Widebandscienticechosounderhasbeeninstalledaccordingtotheinstructions
intheEK80Installationmanual.Alltransceivershavebeensetup,andareoperational
withtheirrespectivetransducers.
TheEK80HarbourAcceptanceTesthasbeenconductedsuccessfully.
Forthistestyouwillneedadesktoporlaptopcomputerwithaspreadsheetprogram.
Context
Inordertomeasurethenoise,youmustrecordthenoisevalueusingthetooltipinthe
echogram.Sincethenoisewillvarywitheachindividualping,youmustvemeasurements
foreachspeed,andcalculatetheaveragenoise.
Youmustmeasurethenoiseforeachsinglechannel,butyoucandoallthesemeasurements
simultaneously.
Tip
Ifyourecordalltherawdatayouretrieveduringthetest,youcangobacklaterandrepeat
thetestusingthereplayle.Youmaythenforexamplerecordmorethanvenoisesamples
foreachspeedtomakeamoreaccuratecurve.
Procedure
1PreparetheEK80toreadthenoisevalues.
aOntheDisplaymenu,clickDisplayOptionstoopenthedialogbox.
bIntheDisplayOptionsdialogbox,enabletheNoisetooltip.
cClickOKtoclosetheDisplayOptionsdialogbox.
2Establishaseparatecommunicationlinewiththebridgetoverifythevesselspeed
duringthetest.
3Startrawdatarecording.
4Repeatthefollowingcycleforeachvesselspeed:
SimradEK80