Hanna Instruments HI 84442 - Manual (Page 25)

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• If the calibration doesn’t complete within 6 minutes the error message “Too much
standard” will be displayed and the calibration can be restarted by pressing Restart
after a new standard is prepared.
• When pump calibration is complete, carefully unscrew electrode holder with pH
electrode, temperature probe and titrant top intact. Hold over rinse beaker and rinse
off with distilled or deionized water. Remove beaker and rinse out.
Verify: The instrument has been calibrated (pH and pump) before performing a lot of titrations.
An electrode calibration in at least one point (4.01 pH buffer) is recommended.
• Refer to Setup Configuration Menu (see the “Setup” section)
to set up the instrument for your measurement.
• Sample preparation: For all measurement samples fill a
beaker up to the 75 mL mark with sample. Place the stir bar
into the beaker and then place the beaker in the appropriate
place on the instrument top.
Note: Water samples must be collected and stored in capped botlles.
• Position the electrode holder on the top of the beaker and
secure it by turning clockwise.
• Before immerse the electrodes in the beaker:
- Carefully rinse the pH electrode and temperature probe
with deionized water.
- Dry electrodes using soft paper.
- Rinse again with the deionized water.
• Immerse the pH and the temperature electrodes approximatively
2 cm (0.8”) into the sample to be tested paying attention not
to touch the stir bar. Use O-Rings provided to secure the pH
electrode in holder.
TITRATION PROCEDURE