Thermo Scientific 42iQD, Инструкция по эксплуатации

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Calibration
Calibration
Thermo Scientific 42iQD Instruction Manual 4-11
For detailed information about the menu parameters and the icons used in
these procedures, see the “ Operation ” chapter.
1. Determine the GPT flow conditions required to meet the dynamic
parameter specifications as indicated in “ Dynamic Parameter
Specifications for Gas Titrator ” earlier in this chapter.
2. Adjust the GPT diluent air and O
3
generator air flows to obtain the
flows determined in “ Dynamic Parameter Specifications for Gas
Titrator ” earlier in this chapter. The total GPT airflow must exceed the
total demand of the analyzer. The 42iQD requires approximately 700
cc/min of sample flow, and a total GPT airflow of at least 1.5 liters/min
is recommended.
a.
Allow the analyzer to sample zero air until the NO
x
response
stabilizes.
b. After the response is stabilized, from the Home Screen, choose
Calibration>Calibrate Background>Calibrate NO
x
Background
.
The Target NO
x
Concentration button will read 0.00. The
Calculated NO
x
Background button will display the background
needed to make the current NO
x
concentration go to 0.00.
c. Press Calibrate to set the NO
x
reading to zero and to save the new
background.
d. Record the stable zero air responses as Z
NOX
.
3. Adjust the NO flow from the standard NO cylinder to generate a NO
concentration of about 80% of the upper range limit (URL) of the NO
range. The exact NO concentration is calculated from:
F
+
F
+
F
NO
x
F
=
]
[NO
D O NO
STD NO
OUT
Where:
[NO]
OUT
= Diluted NO concentration at the output manifold, ppm
NO
STD
= No feed concentration
F
NO
= No flow
F
O
= Ozone flow
F
D
= Dilution flow