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is ready to be sloped at the second buffer.
4. Rinse the pH probe in distilled water and immerse it in the
second buffer solution (either 4.00/4.01 or 9.18/10.01), then
press “SLOPE” key to calibrate. Once the unit calibrates the
second point and the unit will automatically exit the calibration
mode. Dual point calibration is complete.
5. The unit calculates and compensates for the pH electrode
SLOPE deviation corresponding to the values of the two
calibration buffers. After calibration, press and hold “MEA.
/EFF.” key for 5 seconds to display the new electrode
efficiency.
[
Note:
It is recommended to use a new electrode when the
efficiency value is over than 75%.]
C. pH Measurements
To take pH measurements, “STAND” and “SLOPE” icon must be on,
indicating the unit is dual-point calibrated and ready for
measurements. If “STAND” and “SLOPE” icons flash, perform a pH
calibration before taking measurements.
a.
Measurement with an ATC/Temp probe in the pH-
AUTOLOCK mode.
1.
Connect the pH electrode to the BNC connector and the
ATC/Temp probe to the ATC/Temp connector of the unit. The
“ATC” icon will lit up.
2.
Press “MODE” key until “pH” icon and “AUTO” icon lit up.
3.
Rinse the pH electrode and ATC/temp probe with distilled
water and immerse them in the sample to be measured.
Remove any air bubbles trapped around the probe by shaking
or stirring the probe.
4.
Press the “MEA./EFF.” key. The “WAIT” icon will start flashing.
The unit is waiting for a stable reading. The meter will track the
pH value as sensed by the pH electrode and the ATC/Temp
probe.
5.
When the “WAIT” icon disappears and the “HOLD” icon is
displayed, the reading is then locked and will not respond to
further changes from the sample. The pH value shown is the
pH value of the sample at the displayed sample temperature.
[
Note:
For samples that are inherently unstable, the unit will
