Ion concentration
Multi 9420
50
ba75964e04
04/2015
6.2
Calibration
6.2.1 Why calibrate?
Ion-selective electrodes age and are temperature-dependent. This changes
the slope. As a result, an inexact measured value is displayed. Calibration
determines the calibration line of the electrode and stores this value in the
meter.
Thus, you should calibrate before each measurement and at regular intervals.
6.2.2 When to calibrate?
Before any measurement if possible
After connecting another ISE electrode
6.2.3 Calibration (ISE Cal)
ISE Cal is the conventional
two-point
to
seven-point calibration procedure
that uses 2 to 7 freely selectable standard solutions. The concentration
expected for the measurement determines the concentration of the calibration
standards.
1.
Connect the ISE combination electrode to the meter.
The pH/mV/ISE measuring window is displayed.
2.
Keep the standard solutions ready.
3.
If necessary, measure the temperature of the standard solutions with a
thermometer.
4.
In the measured value display, select the ISE measuring window with
<
> <
>
and
<M>
.
5.
If necessary, change the ion type in the
ISE setup
/
Ion type
menu.
6.
If necessary, change the unit of the measurement result and calibration
standards in the
ISE setup
/
Unit
menu.
7.
Start the calibration with
<CAL>
.
The calibration display appears.
8.
Thoroughly rinse the electrode with distilled water.
01.08.2013 08:00
Standard
