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3. THE PROGRAMMING MENU
To access to the menu press simultaneously the following keys:
The items to be set are listed (in this order):
1. K CELL (Cell constant):sets the conductivity probe's cell constant nominal value. The values
0.1, 0.7, 1.0 and 10 cm-1 (with tolerances from –30% to +50% of nominal value) are
admitted.
Caution! The cell constant must be inserted before starting the probe calibration.
An ERR signal is generated if the cell constant's actual value exceeds the limits –30% or +50%
of nominal value. In this case it is necessary to check that the value set is correct, that the
calibration solutions are in good state, and then proceed with a new calibration. The cell
constant change entails resetting the previous calibration.
-use the and arrows to modify the displayed value;
-press DATA/ENTER to confirm the modification and go onto the next item;
-press χ/TDS /ESC to cancel the modification;
-to exit the menu, press the °C/°F key again.
2. ALPH_T (Temperature coefficient αT):the temperature coefficient αTis the percentage
measurement of the conductivity variation according to temperature and is expressed in %/°C
(or %/°F). The admitted values vary from 0.00 to 4.00%/°C.
-use the and arrows to modify the displayed value;
-press DATA/ENTER to confirm the modification and go onto the next item;
-press χ/TDS /ESC to cancel the modification;
-to exit the menu, press the °C/°F key again.
3. REF_TEMP (Reference temperature): it indicates the temperature to which the displayed
conductivity value is standardized and can be equal to 20°C or 25°C.
-use the and arrows to modify the displayed value;
-press DATA/ENTER to confirm the modification and go onto the next item;
-press χ/TDS /ESC to cancel the modification;
-to exit the menu, press the °C/°F key again.
4. TDS (Conversion factor χ/TDS): it represents the ratio between the measured conductivity
value and the total quantity of dissolved solids in the solution, expressed in mg/l (ppm) or g/l
(ppt). This conversion factor depends on the nature of the salts present in the solution: in the
field of water quality treatment and control, where the main component is CaCO3 (Calcium
Carbonate), a value of 0.5 is usually used. For agriculture water, for fertilizers preparation, and
in hydroponics, a factor of about 0.7 is used. The range is 0.4...0.8:
-use the and arrows to modify the displayed value;
-press DATA/ENTER to confirm the modification and go onto the next item;
-press χ/TDS /ESC to cancel the modification;
-to exit the menu, press the °C/°F key again.
