16
Calibrating the compact controller for inductive conductivity
16.1 Calibrating
[CAL]
the conductivity sensor
The following calibration functions are available depending on the
type of sensor:
n
Calibrate the cell constant
n
Calibrate the temperature coefficient
n
Calibrate the zero point
Correct sensor operation
–
Correct measurement and metering is only
possible if the sensor is working perfectly.
–
Refer to the sensor's operating instructions.
Incorrect calibration
An error message ‘ERR’ appears if the result of
the calibration lies outside the specified tolerance
limits. In this case, the current calibration is not
applied.
Check the prerequisites for calibration and clear
the error. Then repeat calibration.
If the calibration is again incorrect, refer to the
information provided in the sensor operating
instructions.
During calibration, the controller sets the control outputs to
‘0’ .
Exception: If a basic load or a manual control variable has been
set. This remains active. The mA standard signal output is frozen.
When calibration has been completed successfully, all the error
checks relating to the measured value are restarted. The controller
saves the data determined for the cell constant and temperature
coefficient when calibration is successful.
The conductivity sensors can be calibrated using 3 different
methods. The cell constant is adjusted directly or indirectly with all
methods:
n
Calibration compared to a reference solution
n
Calibration compared to a reference measurement (e.g.
manual measuring device)
n
Calibration by entering a precisely known or determined cell
constant
Calibrating the compact controller for inductive conductivity
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Summary of Contents for DULCOTROL DWCa
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