Xylem wtw Multi 3410, Руководство по эксплуатации

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Operation
Multi 3410
41
ba75863y18 01/2015
4.6.4 pH calibration
Why calibrate? During the operation of an IDS pH sensor, the zero point (asymmetry)
and slope of the sensor change with time.As a result, an inexact mea-
sured value is displayed. Calibration determines the current values of
the zero point and slope of the pH sensor and stores them in the mea-
suring instrument.
Thus, you should calibrate at regular intervals.
When do you have to
calibrate?

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.
mV resolution 0.1
1
Resolution of the mV display
Reset - Resets all sensor settings to the delivery
condition (see section 4.14.1)
Menu item Possible setting Description
No. Buffer set* pH values at
1
VariCal
Any Any
2
NIST/DIN
DIN buffers according to DIN
19266 and NIST Traceable Buf-
fers
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