Rosemount 755R, Инструкция по эксплуатации

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S
TARTUP AND
C
ALIBRATION
3-4
June 1997 Rosemount Analytical 748213-P Model 755R Oxygen Analyzer
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
T
ABLE
3-1. C
ALIBRATION
R
ANGE FOR
V
ARIOUS
Z
ERO
-B
ASED
O
PERATING
R
ANGES
3.5.1 O
XYGEN
E
QUIVALENT
V
ALUE OF
G
ASES
For computation of background corrections, the analyzer response to each component
of the sample must be shown. Table 3-2 lists the percentage oxygen equivalent
values for many common gases.
The percentage oxygen equivalent of a gas is the instrument response to the given
gas compared to the response to oxygen, assuming that both gases are supplied at
the same pressure .
In equation form:
To select a random example from Table 3-2, if analyzer response to oxygen is +100%,
the response to xenon would be -1.34%.
The oxygen equivalent of a gas mixture is the sum of the contribution of the individual
gas components.
Example: Zero Based Range
At lower range limit, i.e., 0% oxygen, composition of sample is 80% CO
2
, 20%
N
2
.
From Table 3-1, the % oxygen equivalents are CO
2
. -0.623 and N
2
, -0.358%.
% oxygen equivalent of mixture =
0.8 x (-0.623) + 0.2 x (-0.358) = (-0.4984) + (-0.0716) = -0.570% Oxygen
%O
2
Equivalent of Gas =
Analyzer Response to Gas
Analyzer Response to O
2
X 100%