Campbell Scientific CDM-VW300 Series Dynamic Vibrating-Wire Analyzer System - Manual (Page 111)

Appendix G. CRBasic Program Library
'Calculate static digits reading (for troubleshooting)
StaticDigits(1) = StaticStrain(1)/GageFactor/NomBatchFactor
StaticDigits(2) = StaticStrain(2)/GageFactor/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
SlowSequence
Scan (5,sec,10,0)
'Rainflow-Histogram call must be in a slow sequence scan
CDM_VW300Rainflow (CPI_ADDR,RF1(),RF2(),RF3(),RF4(),RF5(),RF6(),RF7(),RF8())
CallTable rainflhist
NextScan
EndProg
G.1.12 50 Hz Measurement Example — One CDM-VW300, Two
Geokon 4000 Sensors with FieldCal() and CardOut() to
CF
'===Geokon4000-50Hz2ChEventCard_4-22-13.CR3===
'CR3000 datalogger
'CDM-VW300 vibrating-wire analyzer
'Program to read 50-Hz dynamic data from one CDM-VW300 measuring two Geokon 4000 strain gages.
' Write data to CF card at each event.
' Demonstrate use of CardOut(), 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 gages
Const GageFactor = 4.062 'G = 4.062 - Gage 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
'Configure the CDM-VW300 device
Dim Enable(2) As Long = { 1, 1}
Dim Max_AMP(2) = { 0.002, 0.002}
Dim F_Low(2) = { 300, 300}
Dim F_High(2) = { 6000, 6000}
'Use Hz^2 (1) instead of Hz (0) so we can get to digits
G-19