8
If measurements are taken successively in different samples, it is
recommended to rinse the electrode thoroughly with deionized water
or tap water and then with some of the next sample in order to prevent
cross-contamination.
The pH reading is affected by temperature. In order to measure the
pH accurately, the temperature effect must be compensated for. To use
the
Automatic Temperature Compensation
feature, connect and
submerse the
HI7662
temperature probe into the sample as close as
possible to the electrode and wait for a few seconds.
If the temperature of the sample is known, manual temperature
compensation can be used by disconnecting the temperature probe.
The display will show the last recorded
temperature reading with the
“°C”
tag blinking.
The temperature can now be adjusted with the
ARROW
keys (from -20.0 °C to 120.0 °C).
ORP MEASUREMENTS (HI2211 only)
An optional ORP electrode must be used to perform ORP measurements
(see Accessories).
Oxidation-reduction potential (REDOX) measurements provide the
quantification of the oxidizing or reducing power of the tested sample.
The surface of the ORP electrode must be clean and smooth in order
to obtain an accurate measurement.
• Press
RANGE
to enter mV range.
• Submerse the tip of the ORP electrode 3 cm
(1¼”) into the sample to be tested and allow
a few seconds for the reading to stabilize.
• The instrument displays the mV reading on
the primary LCD and the temperature on the
secondary LCD.
• If the reading is out of range, the closest full scale value will be
displayed blinking on the LCD.
