Instruction Manual
PD 300
Taking Measurements (pH)
Be sure to remove the electrode storage bottle or
protective rubber cap on the electrode before taking
measurements. To ensure Automatic Temperature
Compensation (ATC) for pH measurements, the DO
or ATC probe must be plugged in and immersed into
the sample.
Figure 15: Measurement mode
To take readings:
1. Rinse the pH electrode with deionised or distilled water before use to remove any
impurities adhering to the probe body. If the pH electrode has dehydrated, soak it
for 30 minutes in electrode storage solution (sold separately).
2. Press
ON
to switch on meter.
3. Press the MODE key to select pH measurement mode. The MEAS annunciator
appears on the top center of the LCD. The ATC indicator appears in the lower right-
hand corner to indicator Automatic Temperature Compensation.
NOTE
For pH manual temperature compensation, you must disconnect the DO electrode from
the 6-pin connector. The ATC indicator will disappear from the display. You also need to
set a manual temperature compensation value. See Section 5.1.2 on page 18 to set
Manual Temperature Compensation
.
4. Dip the probe into the sample. Since the DO electrode contains the temperature
sensor, make sure it is also immersed in your solution.
When dipping the probe into the sample, the sensor or the glass bulb of the electrode
must be completely immersed into the sample. Stir the probe gently in the sample to
create a homogeneous sample.
5. Allow time for the reading to stabilise. Note the reading on the display. If the Ready
indicator is selected on, it will appear when the reading is stable. See below for
more information.
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