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INZ-TN2ZSVS-E
5.3.3 Adjusting moisture interference (Targeted for NO
X
and SO
2
analyz-
ers of special specifications)
Since the compact type gas analyzer performs measurements, using specific wave range of infrared ray,
moisture wavelength over the entire wave range interferes with the measurement, thus causing reading
error.
To reduce the effect, corrective operation is required.
The moisture interference adjustment function is added to NO
X
and SO
2
analyzers, whose wave ranges
overlap in large area.
(1) Adjusting moisture interference (Auto adjustment ALL mode)
1) Select <Maintenance Mode>
→
<6. Interference>, referring to “4.3.6.”
To clear moisture correction value already entered,
2) Move the cursor to <RESET> using the
key.
3) Press the
key, and the cursor moves to <RESET>.
4) Press the
key again, and the moisture correction value is changed to “0.”
To adjust the new correction value, perform reference zero/span calibration as follows.
5) Directly feed dry N2 or dry Air gas into the sample gas inlet at the rate of 0.5 L/min.
(Adjust the flow rate so that the flow checker ball comes to the center.)
6) Select <Dry N
2
> in <Zero Cal.> mode, and then select <ON> for NO
X
and SO
2
only.
7) Perform zero calibration
8) Perform span calibration of NO
X
and SO
2
analyzers.
Then, to feed moisture interference gas (H
2
O, saturated at 2
°
C)
9) Perform bubbling to humidify N
2
gas. Feed the bubbled N
2
gas from the calibration gas inlet
through the 2
°
C dehumidifier (electron cooler).
10) Return to <Maintenance Mode>
→
<6. Interfer-
ence>, and then select <All>.
11) When the interference reading stabilizes in about
3 minutes, press the
key twice.
12) The reading becomes “0” and “correction value”
is input.
Moisture interference adjustment has now been completed.
Interference
reading
Correction
value
<ON>
• Directly feed dry zero gas and dry span gas to perform reference zero/span calibration.
• Select a gas for zero calibration mode in Dry N
2
setting.
Caution on operation
