wtw Cond 3110 - Cell Constant Management

Cond 3110 Operation
19
ba75792e02 11/2008
4.3 Determining/setting up the cell constant [C]
Why determine/set up
the cell constant?
Due to aging, the cell constant slightly changes. As a result, an inexact
measured value is displayed. Calibration determines the current value
of the cell constant and stores this value in the meter.
Thus, you should calibrate at regular intervals.
You can either determine the cell constant of the conductivity
measuring cell in the range 0.450 ... 0.500 cm
-1
or 0.800 ... 0.880 cm
-1
by calibration in the control standard 0.01 mol/l KCl, or adjust it
manually in the range 0.800 ... 0.880 cm
-1
.
Besides, the fixed cell constant 0.475 cm
-1
can be selected.
Cleaning interval (Int.C) After the adjusted cleaning interval has expired the sensor symbol
flashes and thus reminds you to clean the measuring cell. It is still
possible to measure.
The cleaning interval (Int.C) is set to 180 days (d180) in the factory. You
can change the interval (see section 4.5.2).
Note
In order to maintain the high measurement accuracy of the measuring
system, clean the measuring cell and recalibrate after the cleaning
interval has expired.
4.3.1 Determining the cell constant (calibration)
Determining the cell
constant
(calibration in control
standard)
1 Press <CAL> repeatedly until CAL CELL is displayed.
2 Press <ENTER> or <CAL_> to confirm the selection of CAL
CELL.
The cell constant of the last calibration is displayed.
L
CL
E
L
A
C