Teledyne t320u Manual Do Utilizador

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13. 
THEORY OF OPERATION 
The T300/T300M Gas Filter Correlation Carbon monoxide Analyzer is a 
microprocessor-controlled analyzer that determines the concentration of carbon 
monoxide (CO) in a sample gas drawn through the instrument.  It requires that the 
sample and calibration gases be supplied at ambient atmospheric pressure in order to 
establish a stable gas flow through the sample chamber where the gases ability to absorb 
infrared radiation is measured. 
Calibration of the instrument is performed in software and does not require physical 
adjustments to the instrument.  During calibration, the microprocessor measures the 
current state of the IR Sensor output and various other physical parameters of the 
instrument and stores them in memory. 
The microprocessor uses these calibration values, the IR absorption measurements made 
on the sample gas along with data regarding the current temperature and pressure of the 
gas to calculate a final CO concentration.   
This concentration value and the original information from which it was calculated are 
stored in one of the unit’s internal data acquisition system (DAS - See Sections 7) as 
well as reported to the user via front panel display display or a variety of digital and 
analog signal outputs. 
13.1. MEASUREMENT METHOD 
This section presents measurement principles and fundamentals for this instrument.  
13.1.1. BEER’S LAW 
The basic principle by which the analyzer works is called the Beer-Lambert Law or 
Beer’s Law.  It defines how light of a specific wavelength is absorbed by a particular gas 
molecule over a certain distance.  The mathematical relationship between these three 
parameters is: 
I = I
o
 e
Lc 
 Equation 
13-1 
Where:  
I
o
 
is the intensity of the light if there was no absorption.   
06864B DCN6314