wtw Cond 3210, Руководство по эксплуатации

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Operation Cond 3210
30 ba75794e07 07/2017
4.4.5 Determining the cell constant (calibration in
control standard)
Why determine the cell
constant?
Aging slightly changes the cell constant, e.g. due to coatings. As a
result, an inexact measured value is displayed. The original character-
istics of the cell can often be restored by cleaning the cell. Calibration
determines the current value of the cell constant and stores this value
in the meter.
Thus, you should calibrate at regular intervals (we recommend: every
6 months).
Procedure You can determine the actual cell constant of the conductivity measur-
ing cell by calibrating with the control standard in the following ranges:
The cell constant is determined in the control standard, 0.01 mol/l KCl.
Cell constants outside the ranges quoted above cannot be calibrated.
Stability control
(AutoRead)
In calibration, the Stability control function (AutoRead) is automatically
activated.
Display calibration data You can have the data of the last calibration displayed (see section
4.4.6).
Calibration evaluation After calibration, the meter automatically evaluates the current status of
the calibration. The evaluation appears on the display and in the cali-
bration record.
Measurement /
Temperature unit
°C
°F Temperature unit,
degrees Celsius or degrees
Fahrenheit.
All temperature values are dis-
played with the selected unit.
Reset - Resets all sensor settings to
the delivery condition (see
section 4.6.1).
Menu item Possible
setting Explanation

0.450 ... 0.500 cm
-1
(e.g. TetraCon 325, nominal cell constant 0.475 cm
-1
)

0.800 ... 0.880 cm
-1
(e.g. KLE 325 with a nominal cell constant of 0.840 cm
-1
)
In the default condition, the calibrated cell constant of the meter is set
to 0.475 cm
-1
(conductivity sensor TetraCon 325).