VWR 662-2380, Instruction Manual

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After finishing calibration in the first buffer rinse the electrode and
temperature probe in distilled water and dry them with tissue paper and start
calibration in next buffers (Pic. 7.C) by repeating the last point of the activities
described above.
When the electrode is calibrated, two other electrodes may be calibrated and
marked with the other electrode numbers.
10.4. Calibration with use of standard solutions
In this mode the standard solutions values, compliant with the NIST norm, are
used.
The meter’s memory stores a table with a dependence between
the temperature and pH values for these standard solutions.
If the standard solution‘s value differs from the entered standard value in the
3
rd
decimal place, the factory values may be adjusted in the range ±0.010 pH
(description below). After inserting the temperature probe into the pH
standard its temperature is measured and the pH value corresponding to this
temperature is suggested automatically. There is no need to adjust the
standard solutions temperature.
To perform calibration in standards:
- choose the electrode number ( E1 , E2 or E3) according to the point 9.2
and mark the electrode with this number;
- connect the pH electrode and temperature probe to the pH/mV and t
sockets respectively (Pic. 2);
-
enter the calibration mode: on the measurement screen mark pH, press
and hold the
button until the background turns red (Pic. 7.A).
The previous electrode characteristic is erased;
-
press the
button, the pH measurement parameters screen will
appear;
- press the
SOLUTION
window, choose STANDARD ;
- check and, if necessary, enter the calibration points values according to
the point 10.2;
- put the pH electrode and temperature probe into the solution; do not
touch the vessel‘s walls and bottom. It is advisable to use an electrode
holder. The meter will mark the detected buffer‘s value with frame;
- wait until the reading stabilises (it will be probably slightly different than
the calibration point value).
User‘s manual for PH-2500L pH meter v1.0x