M&C TechGroup PMA 100-L Operator's manual - Manual (Page 22)

M&C Products Analysentechnik GmbH 9-3.12.1-ME
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cal. log-book
M 10.11.99 11:o7
Select
Select Select leads to the following menu point.
12.6.5 Calibration log-book
It is possible to read back the data (date and time) of the
last 9 calibrations via the Direction keys
⇑⇓ .
The kind of calibration is marked as follows:
M
manual calibration.
A fault during the calibration is displayed as:
E M 10.11.99 11:07
Select leads to the beginning of the calibration.
13.Calibration
A calibration is recommended latest every 4 weeks.
The step into the calibration menu happens via the CAL key
or the serial interface.
13.1 Calibration
Zero and span calibration happen sequencely.
The zero gas is given to the ‘Sample in’ connection, located
on the back panel of the PMA100-L oxygen analyser (see 8.1,
fig. 7). A detailed description of the menu-driven handling is
given in chapter 12.
Faults during the calibration procedure are displayed in the
main menu like:
E ... O
2
-calibration
The fault message is also stored in the calibration log-book
with an
E ... followed by the shortcut for the calibration mode,
the date, and the time the calibration is carried out. If the zero
and the span gas concentration deviates more than 100%
to the adjusted concentration, a calibration cannot be carri-
ed out. The stop at the calibration is displayed as an error
message.
13.2 Cross-sensitivity
The paramagnetic measuring principle is based on the very
high magnetic susceptibility of oxygen. In comparison to
oxygen, other gases have such a minor susceptibility, most
of them are not even worth mentioning. Exception to this
are the nitrogen oxides. However, as this gas is in most
cases present in a very low concentration, the error is still
negligible.
The next table shows a list of cross-sensitivities. All values
based on a zero calibration with 100 Vol.-% N
2
and a span
calibration with 100 Vol.-% O
2
. The cross-sensitivities in the
table are valid for 100 Vol.-% of the corresponding gas.