Campbell Scientific 4WFBS120, 4WFBS350, 4WFBS1K 4 Wire Full Bridge Terminal Input Modules - Manual (Page 17)

4WFBS120, 4WFBS350, 4WFBS1K 4 Wire Full Bridge Terminal Input Modules (TIM)
Scan (1,Sec,10,0) 'Scan once a Second
PortSet (1 ,1 ) 'Turn on AM16/32 using C1
I = 1
Delay (0,150,mSec) 'required Delay for AM16/32 multiplexer
SubScan (0,0,16)
PulsePort (2,10000) 'Pulse port C2 hi and low to clock the multiplexer
BrFull (MVpV(I),1,mV7_5C,1,VX1,1,2500,True,True,250,500,1,0) ' Full Bridge measurement
StrainCalc (Strain(I),1,MVpV(I),mV_VZero(I),-1,GF(I),0) ' Strain calculation
I = I + 1 ' Increment I
NextSubScan
PortSet (1 ,0 ) 'Turn on AM16/32 using C1
FieldCalStrain (10,MVpV(),CalReps,0,mV_VZero(),ZeroMode,0,ZeroStartIdx,ZeroCalAvgs,0,STRAIN())
CallTable CalHist
CallTable STRAIN
Next Scan 'Loop up for the next scan
EndProg 'Program ends here
4.1.3.2 Edlog
The following examples for the CR10(X), 21X, and CR7 all have subroutines
that measures the unstrained "zero" output of the strain gage. The examples
calculate strain using equation 4.1.2 for a strain gage with a GF=2. These are
just examples. Besides adding additional measurement instructions, the
programs will probably need to have the scan and data storage intervals altered
for actual applications. The instructions in the subroutine will also need to be
modified for the actual gage factor.
Dataloggers that use Edlog include CR510, CR10(X), 21X, and CR7. The
Edlog instruction that is used to measure strain gages is Instruction 6 – Full
Bridge.
The Input Locations assignments used in CR10(X), 21X, and CR7 Examples
are listed in Table 4-1.
TABLE 4-1. Input Locations Used in
CR10(X), 21X, and CR7 Examples
Addr Name
1 mVperV
2 mVperV_0
3 Vr
4 uStrain
5 Count
6 GF
7 _4e6
8 Mult
9 1_2Vr
10 Vr_1_2Vr
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