Owner's manual
Page40
NAV440UserManual
7430‐0131‐01Rev.F
inthehorizontalplane.UsingNAV‐V ironeffectsIEW2.2,thehardandsoft canbeviewedbyselectingthe
ationMenu
MisalignmentoptionontheConfigur emagneticci
Forcalibrationinstructions,refertoAligningtheMagnetometer
,andviewingth rcleduringthecalibration.
onpage55.
MagnetometerAlignmentUsingCode
Theunitprovidesacommandinterfaceforinitiatingthehardiron/softironcalibrationwithoutusingNAV‐VIEW
2.2.Todoso,senda commandtoinitiatethecalibration,andthenrotatetheusersystem360degrees.The C
WC W
dhastwooptions:auto‐terminationandmanualtermination.
• Withauto‐termination,theunittrackstheyawmovementandafter380degreesofrotationreturnsthe
calibrationcompleteresponse,
comman
CC.Theauto‐terminationsequencecanfalselyterminateifthe360degree
so
rotationisnotcompletedwithintwo(2)minute fthe
WCcommandinitiation.
• Manualterminationrequiressendingasecond
WCcommandwiththeterminationcodeinthepayload.
Manualterminationisagoodoptionwhentheusersystemmovesveryslowly(e.g.,largemarinevessel)and
te
completingthe360degreerotationmayrequiremorethantwominu s.
ThestatusofthemagnetometercalibrationisindicatedbythesoftwareErrorÆdataErrorÆmagAlignOutOfBounds
errorflagavailableinthe
T0packet.YoucanaccessthehardIronScaleRatioandsoftIronScaleRatiocalibrationdata
asconfigurationfieldsinNAV‐VIEW2.2,orbyusingthecommunicationprotocol.Also,thesoftwareErrorbitofthe
ftw
masterFailbytewithintheBITwordistransmittedineverymeasurementpacket.Whentheunithasnotbeen
properlycalibrated,thisso areErrorbitwillbesettofail(high).
Thecalibrationcomplete(
CC)commandresponsemessagecontainstheXandYhardironbias,aswellasthesoft
ironratio.Thisinformationcanbeinterpretedtogiveanindicationofthequalityofthecalibration.Formore
informationonthehardironbiasandsoftironratio,referto
CompensationforMagneticFieldsonpage39.Referto
Chapter9.Communicatingwiththe440fordetailsoftheWC andCCcommands.
InstallationGuidelines
FieldInstallation
• Forapropercalibrationandalignment,the440Seriesunitmustbeinstalledinitsoperatingenvironment,
suchasthelandvehicleoraircraftinwhichitwillbeused.