Lab 865
pH value
ba77145e02
12/2017
21
5
pH value
5.1
Measuring
5.1.1 Measuring the pH value
When connecting an earthed PC, measurements cannot be performed in
earthed media as the values would be incorrect.
The USB interface is not galvanically isolated.
Stability control
(AutoRead)
& HOLD function
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
as soon as the measured value is outside the stability range
when the automatic
Stability control
is switched off.
You can activate or switch off the automatic
Stability control
function (see
To ensure the high measurement accuracy of the measuring sys-
tem, always measure with a calibrated electrode (see section 5.2
C
1.
Connect the pH electrode to the meter.
2.
If necessary, select the measured parameter with
<M>
.
3.
When measuring without temperature sensor:
Temper the test sample or measure the current temperature and enter it
with
<
> <
>
.
4.
Immerse the pH electrode in the test sample.
The measured value is checked for stability (automatic stability control).
The display of the measured parameter flashes.
5.
Wait for a stable measured value.
The display of the measured parameter no longer flashes.
pH
6.949
24.8
°C
01.02.2014
08:00
Menu
USB output
