wtw Multi 3430, Руководство по эксплуатации

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Multi 3430 Operation
41 ba75865e02 12/2009
4.6.4 pH calibration
Why calibrate? IDS pH sensors age. This changes the zero point (asymmetry) and
slope of the IDS pH sensor. As a result, an inexact measured value is
displayed. Calibration determines the current values of the zero point
and slope of the IDS pH sensor and stores them in the measuring
instrument.
Thus, you should calibrate at regular intervals.
When do you have to
calibrate?
z
When the calibration interval has expired
Buffer sets for
calibration
You can use the buffer sets quoted in the table for an automatic calibra-
tion. 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 val-
ues
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
7 Merck 4 * 2.000
4.000
7.000
10.000
20°C