9-32
Chapter 9: Inspection and Maintenance
42/24-10 EN Rev. 9
Cross-Sensitivity Alignment
Electronic Cross-
Sensitivity Correction
AO2000 offers the ability to electronically correct cross sensitivity, in contrast to
using purely physical methods (for example, for infrared absorption, optical filter
or flowing reference gas).
Electronic cross sensitivity correction is possible with the Caldos25, Caldos27,
Limas11, Magnos206 and Uras26 analyzer modules. In addition, this function must
be factory-set per customer order. It is configured as a function block application.
A detailed description of the function block
Cross sensitivity correction
is
contained in the Technical Bulletin “AO2000 Function Blocks – Descriptions and
Configuration” (Publication No. 30/24-200 EN).
Cross sensitivity correction is an offset correction.
Interference component concentration is continuously measured and corrected by
means of the measurement value. Alternatively, the interference component con-
centration can be entered directly as a correction value during the cross sensitivity
alignment.
Internal and External
Cross Sensitivity
Correction
Interference component concentration can be measured in two ways:
•
Using the analyzer module with which the sample component is measured
(internal cross sensitivity correction, possible only with the Limas11 and Uras26
analyzer modules) or
•
With another AO2000 analyzer module or another analyzer (external cross
sensitivity correction) The correction signal, i.e. the measured value of the
interference component is transferred to the analyzer module with the sample
component to be corrected via the system bus or analog input.
When should a cross
sensitivity alignment
be performed?
A cross sensitivity alignment, i.e. alignment of the cross sensitivity correction
function, should not be performed in normal operation.
We recommend checking the cross sensitivity correction once a year.
Test Gas for Cross
Sensitivity Alignment
One of the following test gases is needed for the cross sensitivity alignment:
•
Either a sample component-free test gas containing the maximum
concentration of the interference component
•
Or the interference component span gas.
Prior to the Cross
Sensitivity Alignment
Prior to the cross sensitivity alignment, the zero and end points of the applicable
sample and interference components must be calibrated with test gases in the
respective analyzer module.
Menu Path
MENU
→
Maintenance/Test
→
Analyzer spec. adjustm.
→
Cross sensitivity adjustm.
