Owner manual

pH MEASUREMENTpH MEASUREMENT

pH MEASUREMENT

Make sure the instrument has been calibrated

before taking pH measurements.

• Submerse the tip of a properly conditioned

electrode (see page 31) and the temperature

probe approximately 3 cm (1¼”) into the sample

to be tested and stir gently.

Allow time for the electrode to stabilize.

• The pH is displayed on the primary LCD and the temperature on the

secondary LCD.

• The pH reading is out of range, the closest full-scale value will be

displayed blinking on the primary LCD.

• It is also possible to view the mV reading by pressing the RANGE key.

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, this temperature effect must be compensated for. To use the

Automatic Temperature Compensation feature, connect and submerse the

HI 7662 temperature probe into the sample as close to the electrode as

possible and wait for a few minutes.

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” symbol blinking.

The temperature can now be adjusted with the ARROW keys (from

-20.0 ºC to 120.0 ºC).

MTC

SLOW

FAST

POOR GOOD

ATC

3 cm

(1¼")