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8.2 TDS Calibration Notes
1. When a Zero calibration fails, span calibration is lost. Both a Zero and a Span calibration
MUST
be done once the problem has been remedied.
2. The allowable zero range for the Conductivity sensor is 0 to 0.1 ppK. If a zero calibration fails,
please consult the troubleshooting guide (section 24.2).
3. The allowable span range is 75% to 133%. This range is ample to allow for correctly
functioning Conductivity sensors. If calibration fails due to the k factor being outside these
limits, then please consult the Troubleshooting guide (section 24.2) for possible remedies.
4. A Zero calibration should be performed at least monthly.
5. A Standard calibration should be performed at least weekly. Of course, more frequent
calibration will result in greater confidence in results.
6. TDS and Conductivity calibration data are stored in a single area in memory. Ensure that the
hydro
CHEM
has been correctly calibrated for the mode in which it will be used. The
hydro
CHEM
may require re-calibration when alternating between Conductivity and TDS
modes.
7. All calibration information is retained in memory when the
hydro
CHEM
is switched off, even
when the power supply is unplugged. This information can be recalled or printed later using the
GLP function (see section 14).
8. The
hydro
CHEM
displays the value of the standard to which it will attempt to calibrate.
Ensure that the standard value displayed corresponds to the standard that you are using.
8.3 TDS Calibration Messages
4. If a Zero Calibration has been successfully performed, the
hydro
CHEM
will display the
following message and the Zero value of the sensor. For example…
Zero Calibration OK, Zero=0.1ppK
5. If a Standard Calibration has been successfully performed, the
hydro
CHEM
will display the
following message and the span value of the sensor. For example…
2.0ppK Calibration OK, Span=100.1%
6. If a Standard Calibration has failed, the
hydro
CHEM
will display the following message and
the failed span value of the sensor. For example…
2.0ppK Calibration Failed, Span=50.0%