BOREAL LASER GasFinderMC-2, Руководство по эксплуатации

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9.9
Boreal Laser Inc. GasFinderMC Installation Manual — Appendices July 17th 2017
Appendix G — Calibration
The GasFinderMC is shipped already calibrated and can only be recalibrated at a Boreal
Laser facility and not in the fi eld.
The calibration of the
GasFinderMC is
done by passing a known concentration of
gas through a test cell, which is placed in
the path of the laser beam. Gases which are
very reactive or unstable, such as hydrogen
fl uoride, are generated at the time of use
with a permeation tube. The tube is placed
in a temperature-controlled chamber and
emits the calibration gas at a known rate. A
measured fl ow of inert dilution gas creates
a concentration of gas which is traceable
to NIST standards. The calibration data
are stored in the instrument’s software as
a standard reference waveform.
During operation, the GasFinderMC’s internal reference cell is compared with this stored
waveform at frequent intervals. Any signifi cant deviation generates a status code to alert the
user to a potential calibration problem. The
GasFinderMC software can be used to check the
reference cell, as well as to download sample, reference, and calibration waveforms (System
Menus/Internal Arrays Transfer) to verify that the internal calibration system is functioning
correctly. If
GasViewMC is being used, these waveforms can be displayed on the computer
(Options/Arrays Plot Enable and press the ‘Arrays Transfer’ in the GasFinderMC menu or
directly using the Serial Commands as listed in Appendix F).
A technical note detailing the calibration procedure and quality assurance is available from
Boreal Laser Inc.