9
• The pH is displayed 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 primary LCD.
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 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 compen‑
sation can be used by disconnecting the temperature probe.
The display will show the last temperature reading the
“
MTC
” tag and the “
ºC
” tag blinking.
The temperature can now be adjusted with the
ARROW
keys (from –20.0 ºC to 120.0 ºC).
mV/ORP MEASUREMENTS
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 line.