Xylem SI Analytics TITRATOR TitroLine 7500 KF, Руководство по эксплуатации

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This means: The lower the entered stop drift, the longer takes the measurement. If a high stop drift (e.g. 20
µg/min) is entered, the measurement ends significantly faster. Low value = exact measurement, high value =
inexact measurement. As stop drift 2 µg/min are pre-set as standard value. The value can be entered from 0.01
to 25 µg/min.
Diagram 1 shows on the left the titration curve with the measured variable water per time and the derived variable
drift per time.
Water and Drift
0
20
40
60
80
100
120
140
160
0 20 40 60
[s]
W
at
er
0
100
200
300
400
500
600
700
D
ri
ft
Water [µg] Drift [µg/m in]
Drift and Drift tolerance
0
100
200
300
400
500
600
700
0 20 40 60
[s]
D
ri
ft
0
100
200
300
400
500
D
ri
ft
t
o
ler
an
ce
Drift [µg/min] Drift Tolerance [µg/min2]
Diagram 1: Water and drift on the left, drift tolerance on the right
Stop Drift Tolerance
As stop drift tolerance 0.02 µg/min is pre-set as standard value. The value can be entered from 0.01 to 25.00
µg/min.
Fig. 65
In case the drift stop has not been reached as criterion, as new stop criterion is the stop drift tolerance will be
used. It is the derivative of the drift with respect to time. Diagram 2 shows the typical progression of the stop drift
tolerance. Thus, the automatic stop of titrations with side reactions is possible.