TELEDYNE API T200U NOy, Руководство оператора

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Model T200U NOy Option Manual Addendum
07303E DCN7996 17
4.0 PRINCIPLE OF OPERATION
The TAPI Model T200U NOy is designed to measure the concentration of NO,
NO
2
, and other compounds that are too unstable to be measured when taken in
through the normal ambient air sample inlet system. Please refer to the T200U
manual supplied with this system for a general discussion of the operation of a NOx
analyzer. The suite of compounds known collectively as NOy is composed of
roughly 30 compounds. The NOy measurement is generally done in conjunction
with a standard NOx measurement, with the difference between the two being the
concentration of the unstable compounds, sometimes referred to as NOz.
The analyzer measures two independent gas streams. One bypasses the external
Converter and measures NO in the sample. The other pulls the sample through the
external Converter and is displayed as NOy
.
Under normal calibration conditions
the NOy measurement is equivalent to the delivered NOx calibration gases.
The system is composed of four modules:
•
The T200U NOy analyzer, without a Moly converter
•
A 501 NOy Bypass Pump containing:
•
bypass pump
•
flow control
•
sample filtration
•
moly temperature control
•
pneumatic provisions for calibration
•
Externally mounted molybdenum converter (external Converter)
•
External Pump
The T200U NOy system allows the point of sampling to be located in close
proximity to the Converter. This configuration provides minimal time delay
between the sample inlet and the remotely mounted (~10 meters above ground)
external Converter. Minimizing the transit time between the sample inlet and
Converter enables the conversion of labile components of NOy. The equation for
the conversion is:
315 o C
3 NO
Y
+ Mo
---
> 3 NO + MoO
3