Hanna Instruments HI 84529 - Manual (Page 24)

www. hannainst .com 24 Setup/Installation
Electrode
Calibration
Procedure
plug and o-ring on fill hole spout.
8. Using the dropper pipette provided, add a few drops of HI 7072 fill
solution to the electrode. Invert electrode to wet the o-ring and rinse
the electrolyte chamber.
9. Holding the body of the electrode gently press the cap with your thumb.
This permits the fill solution to drain out of the body. Release your thumb
and verify electrode returns to its original position (you may need to
gently assist for this to occur).
10. Fill electrode body with HI 7072 fill solution until solution volume is just
below fill hole.
Note: During measurement always operate reference electrode with the fill
hole open.
Measurement
Place pH electrode and reference electrode into electrode holder and connect
the electrodes to the instrument.
Rinse the pH and reference electrodes with distilled or deionized water.
Immerse the pH and reference electrodes 1.5 cm (0.6”) in the sample and stir
gently for a few seconds.
For a faster response and to avoid cross-contamination of the samples, rinse
the electrodes with a few drops of the solution to be tested, before taking
measurements.
It is recommended to calibrate the instrument frequently, especially if high
accuracy is required. The pH electrode should be recalibrated:
1. Whenever the pH electrode is replaced
2. At least once a week, but daily is advised
3. After testing aggressive chemicals and after the electrode is cleaned
4. When high accuracy is required
5. If the pH calibration expired warning is displayed during measurement
Every time you calibrate the instrument use fresh buffers and clean the
electrode.
Electrode
Preparation
Procedure