Ph Calibration - wtw Multi 3420 Operating Manual

Multi 3420
Menu item
Alternative temperature
pH resolution
mV resolution
Reset
Why calibrate?
When do you have to
calibrate?
Buffer sets for
calibration
ba75864y18 01/2015
Possible setting
on
off
0.001
0.01
0.1
0.1
1
-

4.7.4 pH calibration

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 the calibration interval has expired
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*
VariCal
1
2
NIST/DIN
DIN buffers according to DIN
19266 and NIST Traceable Buf-
fers
3
TEC
WTW Technical buffers
Description
Takes the measured temperature value from
an IDS sensor.
This menu item is only available if an IDS
adapter and an IDS sensor with temperature
sensor are connected.
Resolution of the pH display
Resolution of the mV display
Resets all sensor settings to the delivery
condition (see section 4.15.1)
Operation
pH values at
Any Any
1.679 25 °C
4.006
6.865
9.180
12.454
2.000 25 °C
4.010
7.000
10.011
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