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In order to take pH measurements, follow the next steps:
• Submerge the tip of pH electrode 2 cm (0.8’’) and the temperature probe into the sample to
be tested and stir gently. Allow time for the electrode to stabilize. When the reading becomes
stable, the
(unstable measurement) symbol will disappear.
• If the pH reading is less than -2.00 pH or greater than 16.00 pH, the closest full-scale value
will be displayed blinking.
If measurements are taken successively in different samples, it is recommended to rinse the
electrodes thoroughly with deionized or distilled water and then with some of the next sample to
prevent cross-contamination.
The pH measurement is affected by temperature. In order to have accurate pH measurements, the
temperature effect must be compensated for. To use the Automatic Temperature Compensation
(
ATC
) feature, connect and submerge the
HI 7662-T
temperature probe into the sample as close
as possible to the electrode and wait for a few seconds. The
“ATC”
message will be shown on the
display. Automatic Temperature Compensation will provide pH corrected values for the measured
temperature. If Manual Temperature Compensation (
MTC
) is desired, the temperature probe must
be disconnected from the instrument.
The default temperature of 25 °C (77 °F) or the last temperature reading will be displayed
preceded by the symbol and the
“MTC”
message.
The temperature can be adjusted with the
ARROW
keys (from -20.0 to 120.0 °C).
