Thermo Scientific 42iQTL, Инструкция по эксплуатации

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Calibration
Calibration
4-14 42iQTL Instruction Manual Thermo Scientific
6. Sample this NO concentration until the NO and NO
x
responses have
stabilized, then measure and record the NO concentration as [NO]
ORIG
.
7. Adjust the O
3
generator in the GPT system to generate sufficient O
3
to
produce a decrease in the NO concentration equivalent to about 80%
of the URL of the NO
2
range. The decrease must not exceed 90% of
the NO concentration determined in Steps 5 and 6 above.
8. When the analyzer responses stabilize, record the resultant NO
concentrations as [NO]
REM
.
9. Press the Back button to return to the Calibration menu, and choose
Calibrate NO
2
Span Coefficient .
The user sets the span concentration by pressing the Edit NO
2
Span
Concentration button. The Calculated NO
2
Span Coefficient button
will show what the span coefficient will be set to if the Calibrate button
is pressed. Pressing the Calibrate button will save the new NO
2
span
coefficient and calibrate the instrument.
10. Enter the NO
2
calibration gas concentration using the pushbuttons,
and then press Calibrate to concentration to reflect the sum of the
following: the NO
2
concentration generated by GPT, ([NO]
ORIG
-
[NO]
REM
), and any NO
2
impurity.
The exact NO
x
concentration is calculated from:
F
+
F
+
F
]
NO
[ x
F
+ )
]
[NO -
]
([NO =
]
NO
[
D O NO
IMP
2 NO
REM ORIG OUT
2
Where:
[NO
2
]
OUT
= diluted NO
2
concentration at the output manifold, ppm
[NO]
ORIG
= original NO concentration, prior to addition of O
3
, ppm
[NO]
REM
= NO concentration remaining after addition of O
3
, ppm
The analyzer does a one point NO
2
span coefficient calculation,
corrects the NO
2
reading for converter inefficiency, and then adds the
corrected NO
2
to the NO signal to give a corrected NO
x
signal.
If the analyzer calculates a NO
2
span coefficient of less than 0.96, either
the entered NO
2
concentration is incorrect, the converter is not being
heated to the proper temperature, the instrument needs servicing (leak