Raymarine i70 - Performing a Speed Run Calibration Using SOG; Calibration Table

Measuringanauticalmile
1.Startingpoint(startstopwatch)
2.Measuredmile
3.Endpoint(stopstopwatch)
4.Firstpairofmarkers
5.Secondpairofmarkers
Toprovideamoreaccuratereadingthevessel
shouldmakebetween4to6runsinbothdirections
toallowfortideandwindconditions.Theaverage
ofthetimetakenoverallrunsshouldbeusedto
calculateLogSpeed.
Thevesselspeedcanthenbeworkedoutbytaking
thedistancetravelled(1nauticalmile)anddividingit
bytheaveragetimetakentoperformtherun.The
resultingcalculationisyouraveragespeedinknots.
PerformingaSpeedRunCalibration
usingSOG
Ifahigherlevelofprecisionisrequiredthan
thatachievedwiththe1PointSpeedCalibration
procedure,aSpeedRunCalibrationshouldbe
performed.TheSpeedRunCalibrationwillensure
thattheLogSpeedreadingisaccurateoverthe
vessel’sfullspeedrange.
Prerequisites:
•SOGdatamustbeavailable.
•Youwillneedtobeunderway,withsufcientspace
tomaneuverunhindered.
•Inordertoachieveaccurateresults,water
conditionsmustbecalmwithzerotideandzero
current.
Note:SpeedRunCalibrationisnotavailablewhen
connectedtoaSpeedPod.
Thestepsbelowdetailthemethodofcalibrating:
•speedtransducersconnectedviaaniTC-5
•thespeedelementofasmarttransducer
connecteddirectlytotheSeaTalk
ng
network.
Fromafavoritepage:
1.SelectMenu.
2.SelectSet-up.
3.SelectTransducersSet-up.
4.SelectContinue.
Theinstrumentdisplaywillsearchforanddisplay
alistofconnecteddevices.(i.e.iTC-5,DSTor
transducerpod)
5.Selectthedevicethatthetransducer(s)youare
calibratingareconnectedto.
Alistofavailabletransducerdataisdisplayed,
6.*SelectSpeed.
Important:*SteponlyapplicabletoiTC-5.
7.SelectSpeedCalibration.
8.SelectNewcalusingSOG.
Youwillneedtoaddcalibrationpointsatarange
ofspeedsspanningthefullspeedrangeofthe
vessel.Conventionaltransducerscanhaveupto
5calibrationpointsandsmarttransducerscan
haveupto8.Ideallythecalibrationpointsshould
betakenatregularincrementsthroughoutthe
speedrangewiththelastcalibrationpointbeing
closetothevessel’stopspeed.
WiththeSpeedTransducerconnectedtoa
SpeedPodthe5calibrationpointsarexedin
sequenceat2,4,8,16and32knots.When
addingcalibrationpointsduringtheSpeedRun
Calibrationensurevesselspeedisascloseto
thexedcalibrationpointspeedsaspossible,as
thecalibrationfactorappliedwillbethedifference
betweentheactualvesselspeedandthexed
calibrationpointspeed.
9.SelectStart.
10.Ensurethevessel’sspeedissteadyatyourrst
calibrationpointspeedandselectAdd.
11.Repeatstep10forallremainingcalibration
points,ensuringthatthecalibrationpointsare
equallyspacedthroughoutyourvessel’sspeed
rangefromstationarytotopspeed.
Onceallcalibrationpointshavebeensuccessfully
addedtheCalibrationcompletemessageis
displayed.
12.SelectOk.
CalibrationTable
BydefaultSpeedTransducersincludeadefault
setofcalibrationpointswhichareoverwritten
duringthenormalspeedcalibrationprocess.The
calibrationpointsarestoredintheCalibrationTable.
TheCalibrationTablecanbeaccessedfromthe
AdvancedMenu.
FromtheAdvancedMenuyoucan:
•ViewtheexistingCalibrationT able
•Adjusttheexistingcalibrationpoints(Add,Editor
Deletecalibrationpoints)
•EnteranewCalibrationTable
•CheckLogSpeedagainstSOG
Transducercalibration45