wtw pH 3210, Руководство по эксплуатации

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Operation pH 3310
34 ba75802e02 12/2008
4.4.5 pH calibration
Why calibrate? pH combination electrodes age. This changes the zero point
(asymmetry) and slope of the pH combination electrode. As a result, an
inexact measured value is displayed. Calibration determines and
stores the current values of the zero point and slope of the electrode.
Thus, you should calibrate at regular intervals.
When do you have to
calibrate?
z
After connecting another combination electrode
z
When the calibration interval has expired
Buffer sets for
calibration
You can use the buffer sets quoted in the table for an automatic
calibration. The pH values are valid for the specified temperature
values. The temperature dependence of the pH values is taken into
consideration during the calibration.
No. Buffer set* pH
values
at
1 ConCal Any Any
2 NIST/DIN
DIN buffers according to DIN 19266
and NIST Traceable Buffers 1.679
4.006
6.865
9.180
12.454
25 °C
3 TEC
WTW Technical buffers 2.000
4.010
7.000
10.011
25 °C
4 Merck 1* 4.000
7.000
9.000 20°C
5 Merck 2 * 1.000
6.000
8.000
13.000
20°C
6 Merck 3 * 4.660
6.880
9.220 20°C