Xylem CG 842 - Manual (Page 22)

Operation
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4.2.1 Measuring the pH value
AutoRead AR
(Drift control)
The AutoRead function (drift control) checks the stability of
the measurement signal. The stability has a considerable ef-
fect on the reproducibility of the measured values.
For identical measurement conditions, the following criteria
apply:
l pH value: better than 0.02 (setting time: > 30 s)
1 Perform the preparatory activities according to sec-
tion 4.2.
2 Immerse the pH electrode into the test sample.
3 Press the <pH> key until pH appears in the status
display. The pH value appears on the display.
1 Call up the pH measuring mode by pressing <pH>.
2 Activate the AutoRead function by pressing <auto
read>.
The current measured value is frozen (Hold function).
3 Start the AutoRead function by pressing
<run/enter>.
AR flashes on the display until a stable measured val-
ue is reached.
4 If necessary, start the next AutoRead measurement
by pressing <run/enter>.
5 To terminate the AutoRead function: Press the <auto
read> key.