Teledyne MODEL T703 Manual Do Utilizador

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Teledyne API T703 Calibrator Operation Manual 
Theory of Operation 
 
173 
 
UV 
Source 
ABSORPTION TUBE 
UV Detector 
Sample Gas OUT 
Sample Gas IN 
Window 
Window 
Absorption Path Length = 42 cm 
Photometer 
Pre amp 
PCA 
O-5 VDC 
analog signal  
to 
Motherboard 
Analog current 
signal is output by 
Detector 
 
Figure 9-19: 
O
3
 Photometer Absorption Path 
 
9.6.1.4. Interferent Rejection 
It should be noted that the UV absorption method for detecting ozone is subject to interference from a number of 
sources.  The  has T703’s photometer been successfully tested for its ability to reject interference from sulfur 
dioxide, nitrogen dioxide, nitric oxide, water, and meta-xylene. 
While the photometer rejects interference from the aromatic hydrocarbon meta-xylene, it should be noted that 
there are a very large number of other volatile aromatic hydrocarbons that could potentially interfere with ozone 
detection.  If the T703 calibrator is installed in an environment where high aromatic hydrocarbon concentrations 
are suspected, specific tests should be conducted to reveal the amount of interference these compounds may 
be causing. 
07223B DCN6378