Process Unit 73 LF - Knick

Automatic Calibration with Standard
Calibration Solution
For automatic calibration, the cell is immersed in a
standard calibration solution.
From the measured conductance and temperature,
the Process Unit 73 LF automatically calculates
the cell constant.
Temperature dependence of the calibration solution’s
conductance is taken into account by the
Process Unit.
During calibration, output current (1 and 2) and
controller output are frozen at their last values;
limit contacts are disabled, contact ”probe” is enabled.
What you have to know for calibration
Use only fresh calibration solutions!
The calibration solution must be selected during
parameter setting (see page 9–13).
Accuracy of calibration depends on exact detection
of the calibration solution’s temperature: Using
the measured or entered temperature, the Process
Unit 73 LF determines the setpoint for the calibration
solution from a stored chart.
Note the response time of the temperature probe!
For exact determination of the cell constant, wait
until the temperatures of temperature probe and
calibration solution have balanced.
Calibration 6–5