Emerson NGA2000 PMD Manual Do Utilizador

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Instruction Manual 
760007-A 
July 2003 
 3-6     Operation                                                                                Rosemount Analytical Inc.    A Division of Emerson Process Management 
Model NGA2000 PMD
pressed range.  Table 3-3 below shows rec-
ommended zero and span standard gases for 
suppressed range oxygen indication in an Ar-
gon background.
 
 
RANGE % OXYGEN 
RECOMMENDED ZERO 
STANDARD GAS 
RECOMMENDED SPAN 
STANDARD GAS 
0 to 1 
Nitrogen 
0.9% O
2
, balance N
2
 
0 to 2.5 
Nitrogen 
2.3% O
2
, balance N
2
 
0 to 5 
Nitrogen 
4.5% O
2
, balance N
2
 
0 to 10 
Nitrogen 
9% O
2
, balance N
2
 
0 to 25 
Nitrogen 
Air (20.93% O
2
0 to 50 
Nitrogen 
45% O
2
, balance N
2
 
0 to 100 
Nitrogen 
100% O
2
 
 
Table 3-2.  Calibration Range for Various Zero Based Operating Ranges 
 
 
 
RANGE % OXYGEN 
RECOMMENDED ZERO STANDARD 
GAS 
RECOMMENDED SPAN 
STANDARD GAS 
50 to 100 
50 - 50.5% O
2
 Balance AR 
100% O
2
 
70 – 100% 
70 – 70.5% O
2
 Balance AR 
100% O
2
 
98 – 100% 
98 – 98.5% O
2
 Balance AR 
100% O
2
 
99 – 100% 
99 – 99.5% O
2
 Balance AR 
100% O
2
 
 
Table 3-3.  Calibration Range for Various Suppressed Range Operations 
 
 
 
If the user is unable to calibrate the Analyzer 
Module (i.e., when ZERO or SPAN is initiated, 
nothing happens), a possible solution relates 
to the use of an incorrect gas for zeroing or 
spanning (e.g., using a high concentration gas 
to zero or a zero gas to span the Analyzer 
Module).  Recalibrating with the appropriate 
gas(es) WILL NOT correct the problem be-
cause the ZERO OFFSET or SPAN FACTOR 
has been set to an extreme value in the proc-
ess. 
To remedy the problem, do the following: 
1.  Select the following from the Main Menu:  
Expert Controls and Setup (enter security 
code if necessary), Analyzer Module 
Setup, and Calibration Parameters. 
2.  Using the down arrow, select Zero 
Ranges, press ENTER and, using the 
up/down arrows, toggle to SEPARATE.  
Do the same for the Span Ranges selec-
tion.  Do not press ESCAPE at any time 
unless retention of prior settings is de-
sired. 
3.  Return to the Main Menu (HOME) and 
make the following selections:  Expert 
Controls and Setup (enter security code if 
necessary), Expert Analyzer Controls, 
CAL softkey, FACTORS softkey, and