2 measuring the ph value, Measuring the ph value – Xylem pH/ION 3400i ION SELECTIVE ELECTRODE ANALYZER User Manual
Page 17

pH/ 3400i
Operation
17
4.2.2
Measuring the pH value
Setting the resolution
AutoRead AR
(drift control)
The AutoRead function (drift control) checks the stability of the mea-
surement signal. The stability has a considerable impact on the repro-
ducibility of the measured values.
For identical measurement conditions, the following criteria apply:
1
Perform the preparatory activities according to section 4.2.1.
2
Immerse the pH electrode in the test sample.
3
If required, enter the temperature of the test sample with <
▲>
<
▼> while keeping the <RUN/ENTER> key depressed.
4
Press the <
▲> <▼> keys until pH appears in the status display.
The pH value appears on the display.
mV/pH
mol/L
8
Auto Store
TempError
RCL
LoBat
AutoCal DIN
CalError
ARng AR
AutoCal TEC ConCal
Time
Baud
Day.Month No.
Ident
Year
1
U
%
°F
S
mg/L
% ppm
ISE
8
4
2
2
99
6
°C
TP
pH
1
Press the <RUN/ENTER> key and hold it down.
2
Press the <M> key. The measured values are displayed with a
high resolution, e.g. pH = 4.012.
3
Press the <RUN/ENTER> and <M> key once more.
The measured values are displayed with a low resolution, e.g.
pH = 4.01.
Reproducibility
Response time
Better than 0.02
> 30 seconds
1
Call up the pH measuring mode with <M> and <
▲> <▼> .
2
Activate the AutoRead function with <AR>.
The current measured value is frozen (hold function).