Teledyne t320u Manual Do Utilizador

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Teledyne API – Model T300/T300M CO Analyzer 
Theory of Operation 
303
 
13.2.1.3. SUMMARY INTERFERENCE REJECTION 
The basic design of the T300/T300M rejects most of this interference at a 300:1 ratio.  
The two primary methods used to accomplish this are: 
 The 
4.7μm band pass filter just before the IR sensor which allows the instrument to 
only react to IR absorption in the wavelength affected by CO.   
  Comparison of the measure and reference signals and extraction of the ratio 
between them. 
 Pneumatic 
Operation 
 
CAUTION – G
ENERAL 
S
AFETY 
H
AZARD 
 
It is important that the sample airflow system is both leak tight and not pressurized 
over ambient pressure. 
Regular leak checks should be performed on the analyzer as described in the 
Procedures for correctly performing leak checks can be found in Section 11.3.3.  
An internal pump evacuates the sample chamber creating a small vacuum that draws 
sample gas into the analyzer.  Normally the analyzer is operated with its inlet near 
ambient pressure either because the sample is directly drawn at the inlet or a small vent 
is installed at the inlet.  There are several advantages to this “pull through” 
configuration. 
06864B DCN6314