Campbell CDM-VW300 Series, Руководство пользователя

Страница: 109 / 118

Appendix G. CRBasic Program Library
G-19
CardOut (0 ,-1)
SampleFieldCal
EndTable
BeginProg
'50 Hz/20msec scan rate
Scan (20,msec,500,0)
CDM_VW300Dynamic (CPI_ADDR,Strain(),DCode()) 'Get unshifted strain
'Now shift the given Strain using the Baseline/Offset value
Strain(1) = Strain(1) + StrainBL(1) : Strain(2) = Strain(2) + StrainBL(2)
'Zeroing calibration for Geokon 4000 Vibrating Wire Strain Gauge
'Strain offset and Temperature baseline readings
FieldCal (0,Strain(),2,0,StrainBL(),ZeroMode,0,1,100) 'Calibrate for 2 seconds
FieldCal (4,Temp(),2,0,TempBL(),ZeroMode,0,1,100)
CallTable dynamic
CallTable CalHist
If TimeIntoInterval (0,1,Sec) Then
CDM_VW300Static (CPI_ADDR,StaticStrain(),Temp(),StrainStdDev()) 'Obtain un-shifted static
'strain
'Calculate static digits reading (for troubleshooting)
StaticDigits(1) = StaticStrain(1)/GaugeFactor/NomBatchFactor
StaticDigits(2) = StaticStrain(2)/GaugeFactor/NomBatchFactor
'Now shift the given StaticStrain using the Offset/Baseline reading to obtain
' final/adjusted StaticStrain
StaticStrain(1) = StaticStrain(1) + StrainBL(1) : StaticStrain(2) = StaticStrain(2) + _
StrainBL(2)
'Calculate static frequency from static digits (for troubleshooting)
StaticFreq(1) = SQR(StaticDigits(1)*1000) : StaticFreq(2) = SQR(StaticDigits(2)*1000)
CallTable static
EndIf
NextScan
EndProg
G.1.13 50 Hz Measurement Example
— One CDM-VW300, Two
Geokon 4000 Sensors with FieldCal() and TableFile() to
CF
'===Geokon4000-50Hz2ChEventTableFile_4-25-13.CR3===
'CR3000 datalogger
'CDM-VW300 vibrating-wire analyzer
'Program to read 50-Hz dynamic data from one CDM-VW300 measuring two Geokon 4000
strain gauges.
'Write data to CF card at each event.
'Demonstrate use of TableFile() with Option 64, DataEvent(), and DataInterval() to conserve
' data
storage.
'IMPORTANT -- Ensure that the CPI address coded on the following line matches the address
'reported for the attached analyzer in the DevConfig or DVWTool software.
Const CPI_ADDR = 1 '<<<<<<<<<<<<<<SET CPI ADDRESS HERE
'Constants specific to the Geokon 4000 strain gauges
Const GaugeFactor = 4.062 'G = 4.062 - Gauge factor taken from sensor manual
Const NomBatchFactor = 0.97 'B=0.97 - Batch Factor taken from calibration sheet provided with
' sensors
'Output will be in Strain, not Digits nor Frequency
Public Strain(2) : Units Strain() = Microstrain 'Measured strain output in units of Microstrain
Public StrainBL(2) : Units Strain() = Microstrain 'Baseline/offset strain reading in units of
' Microstrain (for calibration)
Public DCode(2) As Long 'Dynamic diagnostic code
Public StaticStrain(2) : Units StaticStrain() = Microstrain 'Static (1Hz) strain reading in
' microstrain
Public StaticDigits(2) 'Calculated Static (1Hz) Digits output (for troubleshooting)
Public StaticFreq(2) : Units StaticFreq) = Hz 'Calculated Frequency (1Hz) from static digits
'(for troubleshooting)
Public Temp(2) : Units Temp() = DegC ' Temperature in DegC
Public TempBL(2) : Units TempBL() = DegC ' Temperature Baseline in DegC
Public StrainStdDev(2) : Units StrainStdDev() = Microstrain 'StdDev of dynamic strain readings
Public ZeroMode 'Mode variable for baseline/offset zeroing calibration