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14. PUMP CALIBRATION PROCEDURE
The calibration of the pump must be performed every time the syringe, pump tube, the titrant bottle
or the pH electrode is changed. It is recommended to perform the pump calibration before each set of
titration or after the titrator is left idle for several hours.
• Press
MENU
, select
Setup
and select the corresponding range according to the table below:
Low Range
High Range
0.1 to 5.0 g/L
4.0 to 25.0 g/L
• Verify the electrode has been calibrated in 8.20 pH buffer or in 7.01 pH buffer.
Sample preparation:
Use a clean tip and the 2000 µL automatic pipette to precisely add the
appropriate amount of
HI84502-55
Calibration Standard to a clean beaker as indicated below:
Low Range – 4 mL
High Range – 4 mL
Note:
Failure to use a clean pipette will result in erroneous readings.
• Fill the beaker up to the 50 mL mark with the distilled or deionized water.
• Press
CAL
key. The instrument displays the date and time of the last electrode calibration, and the
last pump calibration.
• Press
Pump
key.
Note:
Do not place the tip into the calibration beaker, place the tip over a waste beaker. A small
amount of titrant is dispensed when the pump resets.
• Press
Start
, wait for the syringe to refill.
50 mL
25 mL
15 mL