Xylem Lab 860 - Manual (Page 20)

Operation Lab 860
20 ba75554e05 01/2010
4.3.1 Measuring the pH value
Stability control SC
(drift control)
The stability control function (drift control) checks the stability of the
measurement signal. The stability has a considerable effect on the
reproducibility of the measured value.
For identical measurement conditions, the following criteria apply:
Drift within 15 sec < 0.02 pH units.
Note
The current measurement with stability control can be terminated at
any time (accepting the current value) by pressing <OK>.
1 Perform the preparatory activities according to page 19.
2 Immerse the pH electrode in the test sample.
3 Using <MODE>, scroll as necessary until the measured
parameter pH is displayed.
8 4 2
2 9 9 6
pH
°C
TP
1 If necessary, call up the measured variable pH with <MODE>.
2 With <SC>, activate the stability control function.
The SC function display indicator appears.
The current measured value is frozen (hold function).
3 Start measurement with stability control with <OK>.
SC flashes until a stable measured value is reached.
This measured value is downloaded to the interface.
4 If necessary, start the next measurement with stability control
with <OK>.
5 To terminate the stability control function: Press the <MODE>
or <SC>
key.