CS525 ISFET pH Probe
‘CR200(X) Series
‘Declare the variable for the pH measurement
Public pHmV
‘Read sensor every 60 seconds
BeginProg
Scan(60,sec)
‘Turn power on, delay for 30000 microseconds, then measure sensor
ExDelSE(pHmV,1,1,Ex1,mV5000,30000,1,0.0)
NextScan
EndProg
4.2.1.2 CR800, CR850, CR1000, and CR3000 Programming
For the CR800, CR1000 and CR3000 dataloggers, Instruction VoltSe is used
to read Single-ended analog sensors. A multiplier of 1.0 and an offset of 0.0
yields millivolts. A corrected multiplier and an offset are required to provide
an output in pH units (see Appendix A).
The VoltSe instruction has the following form:
VoltSe(Dest, Reps, Range, SEChan, MeasOff, SettlingTime, Integ, Mult,
Offset)
Use mV5000 for the range parameter if the sensor’s output option is 0 to
5000 mV. Typically, use mV250 for the range parameter if the sensor’s output
option is
±
300 mV.
The mV250 range option may be inadequate for pH ranges that
are greater than 11 or less than 2. At these extreme ranges,
either use Autorange or mV5000.
NOTE
Below is an example program for CR800, CR850, CR1000, and CR3000
dataloggers when the sensor has a 0 to 5000 mV output.
‘CR1000 Series Datalogger
‘Declare the variable for the pH measurement
Public pHmV
‘Read sensor every 60 seconds
BeginProg
Scan(60,sec,1,0)
‘ Code for VoltSE measurements:
VoltSE(pHmV,1,
mV5000,1,False,0,_60Hz,1,0)
NextScan
EndProg
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