wtw AmmoLyt 700 IQ, Руководство по эксплуатации

Страница: 42 / 58

Calibration and measuring AmmoLyt
®
700 IQ
4 - 22 ba75353e05 03/2006
For measurements in test samples with a pH value > 7, a compensation
for the influence of the pH value may be necessary. The compensation
can, e. g. be performed using the superior process control engineering.
Note
For details, please refer to WTW GmbH.
4.2.2 Potassium compensation
Measuring ammonium in the presence of potassium leads to increased
ammonium values:
Higher measured values caused by potassium can be compensated for
by switching on the
Potassium compens. function and entering the
potassium content in the Settings of sensors and diff. sensors menu
(see section 3.4).
Potassium
compensation for
calibration
The presence of potassium affects the calibration results of the follo-
wing calibration procedures:
!
1 point ref. (2)
!
Simple std. add. (4) )
!
Double std. add. (5)
For these calibration procedures, the current potassium content must
always be determined and entered before or during calibration. The
entered potassium compensation has an effect on the calibration result
and thus on the subsequent measurements.
The calibration procedures, 1 point standard (1) and 2 point stand. (3)
are carried out in standard solutions. Potassium does not interfere
here. An incorrectly set potassium compensation affects the following
measurement.
Potassium con-
tents Ammonium value increased by approx.
10 mg/l K
+
0.7 mg/l
50 mg/l K
+
3.4 mg/l