Campbell Scientific CS526 ISFET pH Probe - Manual (Page 17)

CS526 ISFET pH Probe
7.2.3.4 SplitStr() Instruction
The SplitStr() instruction has the following syntax:
SplitStr(SplitResult,SearchString,FilterString,NumSplit,SplitOption)
SplitResult — an array in which the split string will be stored.
SearchString — the string on which this instruction will operate. This will
be the variable entered for the Dest parameter for the SerialIn()
instruction (see above).
FilterString — enter “String” (this value will be ignored because of the
SplitOption that will be used).
NumSplit — enter 2
SplitOption — enter 0. This splits out numeric values.
7.2.4 Programming for Calibration
To output in pH units instead of digital counts, enter the offset and multiplier
into the datalogger program. Simple program instructions can be used to make
the required periodic calibration easier. See Appendix C, Calibration, for an
example program.
7.3 Calibration
Calibration should be carried out according to the detailed procedure outlined
in Appendix C, Calibration. The calibration should use two or more pH
standards, listed in TABLE 7-4, which are available from Campbell Scientific.
TABLE 7-4. Calibration Standards
pH Part Number
4 25587
7 25586
10 25588
Frequency of calibration depends on the level of accuracy required and the
coating / fouling nature of the measured samples.
8. Troubleshooting
Follow the procedure provided by the Assistance section at the
beginning of this document if the CS526 is not operating properly
and requires return to Campbell Scientific.
The most common causes for erroneous pH data include:
• poor sensor connections to the datalogger
• damaged cables
• scratched chip
• contaminated or clogged diaphragm
NOTE
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