YOKOGAWA PH71, User Manual

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IM 12B03D01-01E
2-4
2. Preparation
2.4 Wetting Cap
The glass electrode should be kept wet during storage. If the glass electrode dries out, it
will take hours to rehydrate and in the meantime the meter may give erroneous readings.
The wetting cap is used to prevent the glass electrode from drying out. Sensors are
shipped with a wetting cap containing a cotton wad moistened with a few drops of water.
For storage replenish the cap with a few drops of water (tap water) and attach to the
sensor firmly.
F0201.EPS
Protective cover
Lug
Slot
To remove cap, rotate counterclockwise
and pull out until lugs on cap clear
protective cover through slots.
Removed cap can be
attached onto sensor cable
during measurement.
Figure 2.1 Wetting Cap
2.5 Manual Temperature Setting
If a sensor without a built-in temperature element (needle type or test tube size pH
sensor) is connected to the meter,
mark will appear on the display. In this case,
measure the temperature of the solution being measured and manually set the measured
temperature into the PH71 meter for reliable measurement. The procedure is described in
Section 5.3 (2), “Manual temperature setting (M.tP) panel.”
Temperature compensation is performed based on a temperature shown on the display of
the PH71 meter. If a temperature shown on the display is different from the actual
temperature of the sample being measured, the displayed measured value may not be
true. The bigger the difference between the temperature displayed on the meter and the
actual temperature of the solution, the bigger the error between the displayed measured
value and the true value.
If mark appears on the display even though a sensor with a built-in temperature
element is connected, refer to Section 7.4.