Ph Calibration; Preparation; One-Point Calibration - Hach sensION+ MM150 Manual

6. Operation

6.3. pH calibration

Important note: Before turning on the instrument, check that the sensor is connected.
The instrument must be calibrated before taking the first pH reading.
The calibration can be performed with 1, 2 or 3 points.

6.3.1. Preparation

1. Fill the tubes with the buffer solutions (note the fill level).
2. Unscrew the protector containing the electrolyte and rinse the sensor with deionized water.
3. Screw the sensor on to the tube containing the first buffer.
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6.3.2. One-point calibration

Stir gently holding the sensor by the handle. Do not hold it by the tube to avoid
heating of the buffer solution.
Follow the diagram on the next page.
One-point calibration is acceptable when pH values around that of the buffer
used are being measured.
One-point calibration only corrects the asymmetry potential of the electrode.
Notes: If the measuring instrument is not used for 5 minutes, it shuts off
automatically.
If an anomaly occurs during calibration, an error message will appear on
screen (see pg. 23).
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sensION+ MM150 HACH 0710.indd ANG:12 sensION+ MM150 HACH 0710.indd ANG:12
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Fig. 6. Preparation
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