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Calibration
Calibration
Adjust Instrument Gain
Set Backgrounds to Zero
4-10
Model 42i Trace Level Instruction Manual
2. Ensure that all flow meters are calibrated under the conditions of use
against a reliable standard, such as a soap-bubble meter or wet-test
meter. All volumetric flow rates should be corrected to 25 °C and 760
mmHg.
3. Precautions should be taken to remove O
from the NO pressure regulator and delivery system prior to the start of
calibration to avoid any conversion of NO to NO
cause significant errors in calibration. This problem can be minimized
by:
a. Carefully evacuating the regulator after the regulator has been
connected to the cylinder and before opening the cylinder valve.
b. Thoroughly flushing the regulator and delivery system with NO
after opening the cylinder valve.
c. Not removing the regulator from the cylinder between calibrations
unless absolutely necessary.
4. Connect the analyzer sample bulkhead input to the output of the GPT
system.
Use the following procedure to adjust the instrument gain. This includes:
Setting the Prereactor, NO and NO
●
Calibrating the NO channel to the NO calibration gas
●
Calibrating the NO
●
The Prereactor, NO and NO
during zero calibration. The background signal is the combination of
electrical offsets, PMT dark current, and trace substances undergoing
chemiluminescence. For more detailed information, see
Prereactor
Backgrounds" in the "Operation" chapter.
Use the following procedure to set the prereactor background. Both the
NO and NO
background screens operate the same way, and the following
x
procedure also applies to the NO and NO
Note The NO channel should be calibrated first and then calibrate the
NO
channel.
▲
x
2
backgrounds to zero
x
channel to the NO
calibration gas
x
x
background corrections are determined
x
background screen.
x
and other contaminants
. Failure to do so can
2
"NO, NOx, and
Thermo Fisher Scientific
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