Emerson Process Management NGA2000 HFID 用户手册

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Instruction Manual 
748297-E 
June 2003 
          Installation 
Rosemount Analytical Inc.    A Division of Emerson Process Management 
2-4 
Model NGA2000 HFID
introduced through the sample inlet at the 
rear of the module. 
 
Zero Gas  -  Analysis is affected by the 
background gas of the sample. Therefore, it 
is recommended to use zero gas with as 
close to the background composition of the 
sample as possible. Normally less than 0.5 
THC as CH
4
 is sufficient. 
Span Gas  -  Span gas consists of a speci-
fied concentration of methane or other hy-
drocarbon in a background gas such as 
nitrogen. Analysis is affected by the back-
ground gas of the sample. Therefore, span 
gas containing the same background gas as 
the sample is recommended. Then, the 
background effect is canceled out. 
h. Sample 
Gas 
Specification 
Sample gas should be nonflammable (be-
low 100% of the sample's LEL). For high 
sensitivity applications requiring background 
gas compensation, contact the factory. 
i. Flow 
Rate 
Specification 
Required sample flow rate is 1.0 L/min. to 
2.5 L/min. for a supply pressure between 5 
and 9 psig.  Flow rate for purge gas should 
be 16 to 18 L/min. Flow rate for regulated 
air should be 2 to 4 L/min. 
j. Pressure/Filtration 
Specification 
Sample Pressure at the SAMPLE inlet 
should be within the range of 345 to 620 
hPa-gauge (5 to 9 psig, 7.0 psig nominal), 
and internally, should be between 206.7 
and 275.6 hPa-gauge (3.0 and 4.0 psig).   
Burner Fuel Pressure should be: 3101 to 
3450 hPa-gauge (45 to 50 psig) for cylinder 
regulator, 1723 hPa-gauge (25 psig) 
nominal for internal pressure.   
Burner Air Pressure should be : 1725 
to 3450 hPa-gauge (25 to 50 psig) for 
cylinder regulator, 1035 hPa-gauge (15 
psig) nominal for internal pressure
Regulated Air Pressure should be 689 
to 1725 hPa-gauge (10 to 25 psig) for 
cylinder regulator. 
Purge Air Pressure should be 689 to 
1380 hPa-gauge (10 to 20 psig). 
Nominal Internal Case Pressure is 
about 0.5 to 1.0 inch of water, and the 
pressure relief valve is set at 1/3 psig 
(nominal). 
CAUTION 
OVER-PRESSURE 
Noncompliance with these specifica-
tions, particularly those concerning 
purge air, could cause over-pressure 
damage to the module. 
Note 
The sample gas and regulated air 
should be filtered for particulates 
down to 2 microns to prevent the 
plugging of pneumatic components. 
k. Leak 
Test 
The analyzer module is completely leak 
tested at the factory.  The user is re-
sponsible for testing for leakage at the 
inlet and outlet fittings on the rear panel.  
The user is also responsible for internal 
leak testing periodically and if any inter-
nal pneumatic components are adjusted 
or replaced (with a test procedure cho-
sen by the user).