Servomex SERVOTOUGH LaserExact 2950, Руководство оператора

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SERVOTOUGH LaserExact Monitor, Operator Manual 02950001A_1
SERVICE PROGRAM
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requirements to the gas parameters and signal quality. The PROPORTIONAL
calibration may be done whenever it appears necessary to the user that the
instrument measurements should be adjusted, for example during measurement of
process gas. Please note the following:
•
All gases can be calibrated individually. The true gas value is specified and
“Calibration” is set to “Yes” from the corresponding dropdown list.
•
For gases that are not to be calibrated, “Calibration” is set to “No” from the
corresponding dropdown list.
It is also possible to auto-calibrate gases. Gas A is calibrated by filling in the true
value and selecting “yes”. Gas B is auto-calibrated by setting the correct value to
zero and select “adjust”. In this case the calibration constants for line amplitude
and line width for gas B are adjusted according to the calibration of gas A. This is
useful if only one calibration gas is available or if the relative ratio of the measured
concentrations after the calibration shall be preserved.
In the example above, NH
3
gas is calibrated to 25 ppm. The calibration constants
for H
2
O will be adjusted accordingly.
Enter your initials for identification of calibration.
Press <Calibrate instrument> to update the instrument with a new calibration. The
instrument will use the currently measured average concentration to perform all
necessary calculations. The new calibration will be stored permanently. The
calibration time will be updated automatically.
SERVOMEX calibrates all instruments under controlled conditions using certified
gas. This calibration is then verified for the specified range of temperature and
pressure. There is no need to calibrate the instrument upon reception.
In the
GLOBAL calibration mode the instrument performs reference
measurements of the absorption line width in addition to the line amplitude. The
calibration constant and reference line width are then adjusted based on these
measurements. This calibration procedure requires stable and controlled
conditions of the reference gas. It should be performed using a test cell and a
certified mixture of measured gas with nitrogen and only if it was verified that the
current calibration is not valid. The procedure requires technical skills and some
experience in handling gas mixtures. As a rule only qualified personnel should
perform GLOBAL calibration after major services. General recommendations
concerning this calibration option are given in Section 5.3. To calibrate the
instrument proceed in the same way as described above for PROPORTIONAL
calibration mode. The only difference is that the program will ask for a password,
which is available from the local distributor or the factory. The GLOBAL calibration,
if performed correctly (ref. Section 5.3), guaranties the validity of the calibration
parameters in the specified pressure and temperature range.
Calibration mode PROPORTIONAL/GLOBAL is common for all gases.
Nevertheless, it is possible to calibrate one gas in global mode and another in
proportional mode. In this case the mode is set to GLOBAL and the line width