TPS smartCHEM-D, Manual, Page: 17 / 60

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3.4 Dissolved Oxygen Calibration Notes
1. The relationship of % Saturation and ppM depends on a number of variables, so always
calibrate in the mode required . Do not try to infer Oxygen content from one mode to another.
2. The smart CHEM -D automatically detects if a TPS ED1 or a YSI sensor is connected. When
the unit has been calibrated for one type, and the other type is then connected, the message
“
Probe
” appears in the Dissolved Oxygen display. It is necessary to re-calibrate for the new
sensor to obtain accurate readings.
3. A zero calibration should be performed at least monthly. In applications where there is a low
level of dissolved oxygen, a zero calibration may have to be done weekly.
4. An air calibration should be performed at least weekly. Of course, more frequent calibration
will result in greater confidence in results.
5. 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).
3.5 Dissolved Oxygen Calibration Messages
1. If a Zero calibration has been successfully performed, the smart CHEM -D will display the
following message and the Zero value of the sensor…
Calibration OK,
Zero=0.0%
2. If a Zero calibration has failed, the smart CHEM -D will display the following message and the
failed Zero value of the sensor. The unit will return to normal display mode with a “
∗∗
” in
place of the decimal point in the Dissolved Oxygen reading.
Calibration Failed,
Zero=15.0%
3. If an Air/Span calibration has been successfully performed, the smart CHEM -D will display
the following message and the Span value of the sensor…
Calibration OK,
Span=101.0%