Teledyne API Model 200AH NO
X
Analyzer Instruction Manual, 06492, Rev. G2
7-13
Table 7-11: Calibration Quality Check
Step
Number
Action Comment
1. Scroll the TEST function
menu until the NO
X
SLOPE is displayed.
The SLOPE value for NO
X
should be 1.0 0.3. If the value is
not in this range, check Section 9.1.6. If the SLOPE value is
in the acceptable range the instrument will perform optimally.
2. Scroll the TEST function
menu until the NO
X
OFFSET is displayed.
This number should be near zero. A value of 0.0 50
indicates calibration in the optimal range. This number
already has the AutoZero value subtracted out and is mainly
the background signal due to the molybdenum converter. If
the OFFSET value is outside this range, check Section 9.1.6.
3. Scroll the TEST function
menu until the NO
SLOPE is displayed.
The SLOPE value for NO should be 1.0 0.3. If the SLOPE
is in the acceptable range the instrument will perform
optimally. If the value is not in this range, check
Section 9.1.6.
NOTE: The NO and NO
X
slopes should be equal within 0.1.
4. Scroll the TEST function
menu until the NO
OFFSET is displayed.
The instrument will now display the NO OFFSET value. It
should also have a value near zero (0.0 50). This number
already has the AutoZero reading subtracted out and should
be near zero. If the OFFSET value is outside this range, check
Section 9.1.6.
7.11. Converter Efficiency Compensation
The converter efficiency factor compensates NO
2
readings for converter efficiency. The NO
2
component of the NO
X
reading is also compensated when instrument is in switching mode. An
efficiency factor of 1.0 disables efficiency compensation, acceptable values are .80 to 1.20.
There are some fault conditions that can be revealed by a NO
2
channel linearity check, such as a
faulty switching valve or a partially plugged converter. For the converter to operate properly
there should be at least a few percent oxygen present in the sample stream.
There are 2 ways to enter the NO
2
converter efficiency.
Method 1 is covered in Table 7-12.
