TPS smartCHEM-D, Manual, Page: 26 / 60

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5.5 TDS Calibration Notes
1. A Zero calibration should be performed at least monthly. In low conductivity applications
(where a zero error is particularly significant), a zero calibration may have to be done weekly.
2. A Standard calibration should be performed at least weekly. Of course, more frequent
calibration will result in greater confidence in results.
3. Conductivity and TDS calibration data is stored separately in memory. Ensure that the
smart CHEM -D has been correctly calibrated for the mode in which it will be used. The
smart CHEM -D does not require re-calibration when alternating between Conductivity and
TDS modes, providing the instrument has been correctly calibrated for each mode on the k
factor sensor to be used.
4. All calibration information is retained in memory when the smart CHEM -D is switched off.
This information can be recalled or printed later using the GLP function (see section 9).
5. The smart CHEM -D 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. Alter
the Standards set-up if necessary (see section 5.2).
6. Calibration settings for k=0.1, k=1.0 and k=10 sensors are NOT stored separately.
The smart CHEM -D requires re-calibration when a new k factor sensor is connected.
5.6 TDS Calibration Messages
1. If a Zero Calibration has been successfully performed, the smart CHEM -D will display the
following message…
Calibration OK,
Zero=0.01ppM
2. If a Standard Calibration has been successfully performed, the smart CHEM -D will display the
following message and the calculated k factor of the sensor. For example…
Calibration OK,
k=0.99
3. If a Standard Calibration has failed, the smart CHEM -D will display the following message
and the calculated k factor of the sensor. For example…
Calibrate Failure,
Check STD=2000.ppM
k=3.64,Exceeds Limit
Notes
1. The allowable k factor range is +/-25% of nominal. This range is ample to allow for correctly
functioning TDS sensors. If calibration fails due to the k factor being outside these limits, then
please consult the Troubleshooting guide (section 17.3) for possible remedies.