Ion Concentration; Measuring; Measuring The Ion Concentration - wtw pH/ION 7320P Operating Manual

pH/ION 7320
Stability control
(AutoRead)
& HOLD function
ba75935e04 12/2017
8

Ion concentration

8.1

Measuring

8.1.1 Measuring the ion concentration

NOTE
When connecting an earthed PC/printer, measurements cannot be
performed in earthed media as the values would be incorrect.
The USB interface is not galvanically isolated.
Incorrect calibration of ion selective electrodes will result in incor-
rect measured values. Calibrate regularly before measuring.
For precise ISE measurements the temperature difference
between measurement and calibration should not be greater that
2 K. Therefore, adjust the temperature of the standard and
measuring solutions accordingly. If the temperature difference is
greater the [TpErr] warning appears in the measured value display.
1. Connect the ISE combination electrode to the meter.
The pH/ISE measuring window is displayed.
2. If necessary, select the ISE display (unit, mg/l) with <M>.
3. If necessary, measure the temperature of the test sample with a ther-
mometer.
4. Calibrate or check the meter with the electrode.
While no valid calibration is available, e.g. in the delivery condition,
"Error" appears in the measured value display.
5. Immerse the electrode in the test sample.
ISE
0.157
25.0
Ag
The stability control function (AutoRead) continually checks the stability of the
measurement signal. The stability has a considerable impact on the reproduc-
ibility of measured values.
The measured parameter flashes on the display
mg/l
°C
12.12.2012
USB output
12:12
Ion concentration
45