Teledyne 201A Manual Do Utilizador

 Analyzer Instruction Manual, 04689, Rev. B1 

The M201A Ammonia Analyzer consists of a modified M200A Nitrogen Oxides Analyzer 
and M501NH Ammonia Converter:   

A functional block diagram of the system is shown in Figure 1. 

The instrument comes in three pneumatic configurations: 

•  The basic system is shown in Figure 3; 
•  The M201A with Z/S valves is shown in Figure 4; 
•  The M201A with External Calibrator Option (ECO) is shown in Figure 5. 

 

Figure 2 can be used to connect the M201A system for installation.  Please note that for a 
M201A with either a Zero/Span or ECO option, you must connect the umbilical cord, 
02255, between the analyzer and the converter assembly. 

The Teledyne API Model 201A Analyzer measures ammonia by converting NH

3

 to nitric 

oxide by the following reaction: 

 

 

4NH

3

 + 5O

2

   

→  4NO + 6H

2

O 

The resulting NO is then measured by the chemiluminescent reaction of NO with ozone.  
Consult Section 4.1 in the M200A manual  (provided with this instrument) for more 
details on NO measurement. 

A molybdenum converter is continuously in the pneumatic pathway, providing the TN 
channel signal.  The 

M501NH 

ammonia converter is periodically switched so both 

converters are in series, creating the TNx signal. 

The ammonia concentration is computed by the difference between the TNx and TN 
channels, as shown in the following equation: 

 

 

 

NH

3

 

→ TNx  - TN 

See the pneumatic diagram in Figure 1. 

The actual formula for computation of ammonia concentration is more complicated than 
the above equation, as it includes converter efficiencies, plus sample temperature and 
pressure.  The difficulty in ammonia measurement is that the molybdenum converter