Siemens RAPIDLAB 248, Operator'S Manual, Page: 33 / 135

Measuring a Short Sample or a Sample with a Bubble
CAUTION:
Special care must be taken to make sure that the sample is
repositioned directly beneath the sensors for which results are
required. For example, for pO
2
and pCO
2
results, the sample must be
positioned under the pO
2
and pCO
2
sensors with no air bubbles present.
For pH results the sample must be positioned under the pH and
reference sensors with no air bubbles present. Air bubbles present
under one of the sensors as a result of incorrect sample repositioning
may lead to erroneous results.
3. When you are satisfied that the sample is correctly repositioned
press
# . The sample analysis continues. The printout shows ‘Short
sample’ or ‘Bubble in sample’.
Cancelling the Sample Analysis
1. If you have enough sample left to repeat the analysis, press * .
2. The sample is flushed out of the measurement block and the display
returns to the
Ready screen.
Requesting an Additional Calibration
The 248 automatically calibrates using one of the user-selectable
methods (see Section 1,
Understanding the System , for details).
The Calibration menu allows additional, user-requested calibrations to
be carried out.
1. From Ready press # for menu , and 1 for Calibration .
2. Press
1
-
6
to select the type of calibration you want.
The 248 displays each stage of the calibration on the status line.
The calibration results are displayed and the 248 confirms when
the calibration is successful.
A successful, user-requested calibration resets the automatic
calibration timer.
The 248 will not allow a partial calibration if a full calibration is
due. For example, if you press
1 when a 2 point calibration is due,
the 248 displays ‘Full 2 point required’.
Calibrating the Barometer
The Calibration menu also allows you to check the atmospheric
pressure and to recalibrate the internal barometer.
1. From
Ready
press
#
for
menu
,
1
for
Calibration
and
7
for
Barometer
.
Operating the System Page 2-9
Main Menu → Calibration
1 Full 1 Point 5 pH 1 Point
2 Full 2 Point 6 pH 2 Point
3 Gas 1 Point 7 Barometer
4 Gas 2 Point
press 1 - 7 or * to Exit