Option
Start logging
measurements
Open data
7.4 Calibration
Calibrations can only be performed once the instrument has been installed and configured.
Note: The temperature sensor is factory calibrated and can only be changed by a Hach representative.
7.4.1 Definitions
To calibrate the gas to measure (main gas), the user usually puts the sensor in the main gas without
any interfering gas.
Calibrations can only be performed once the instrument has been installed, configured and the
channel has been set up. You must also ensure that you have the correct access rights to access the
calibration menu.
Select sensor calibration from the calibration menu.
There are two types of gas sensor calibration available, depending on the gas being measured and
the type of sensor being used:
1. In Air: For Oxygen and Ozone with an EC sensor. The sensor is exposed to air at atmospheric
pressure.
2. Direct value: Any gas with either an EC or TC sensor. This calibration exposes the sensor to a
gas with a known partial pressure, or a liquid sample with a known gas concentration.
7.4.2 EC gas sensor calibration
7.4.2.1 Calibration of the measured gas
1. Before initiating a calibration process, the calibration parameters must be set by pressing on the
Modify button. The last calibration parameters are memorized, so this step can be ignored if the
correct parameters are already set.
Option
Calibration mode
Medium
Concentration unit
type
Concentration unit
Liquid
Description
Only available in Store once mode, this option starts or stops the
measurement recording session. Measurement recording ends
automatically when the buffer is full.
Opens a table showing the measurments stored in the volatile memory
(RAM).
Note: If TPO or TPA calculation is enabled, a "TPO data" or a "TPA data" button
will be available underneath the "Open data" button described above. Pressing
this button will display the TPO or TPA calculated data in a screen similar to that
for standard data.
Description
2 types available, depending on the gas being measured:
• Direct value: Any gas
• In Air (default): For O
Select liquid or gas (direct calibration only)
Partial, fraction or dissolved (dissolved is for calibration in a liquid
only)
The list of available units depends on unit type selected above.
Select as appropriate, available when liquid has been selected in
medium (above).
or O
2
3
English 21