Hanna Instruments HI 84502 - Manual (Page 26)

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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.
• Place the stir bar in the beaker and put the beaker in the
minititrator top.
• Place the probe holder on the top of the beaker and secure it
by turning clockwise.
• Rinse the pH electrode with deionized water and immerse
into the sample until the PTFE reference junction is completely
submerged. Be sure that the tip of the electrode is not hitting
the stir bar. If necessary, additional distilled or deionized
water can be added.
PUMP CALIBRATION PROCEDURE
• Verify the electrode has been calibrated in 8.20 pH buffer or in 7.01 pH buffer.
Sample preparation: Use a clean tip and 2000 uL automatic pipette to precisely add the
appropriate amount of
HI 84502-55 Calibration Standard to a clean beaker as indicated below:
e g n a R w o L e g n a R h g i H
L / g 0 . 5 o t 1 . 0 L / g 0 . 5 2 o t 0 . 4
Low Range - 4 mL
High Range - 4 mL
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: