Lamtec LT2, Руководство по сборке и пусконаладке

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3 Introduction
15
If concentrations of O
2
are higher, more unburned residues (CO/H
2
) oxidise before
the 3-phase limit is reached. The graph below shows the influence of the sensor
voltage U
COe
as a function of the O
2
content.
1000
800
600
400
200
0
0 2000 4000
6000 8000
10000
CO [ppm]
9,5 % O
6
2
% O
2
U [
m
V
]
CO
e
at starting
point with
0% CO
Fig. 3: Sensor voltage U
COe
as a function of O
2
content
We therefore recommend calibrating the characteristic in line with the specific system
by performing a CO reference measurement.
A further indicator for unburned residues (CO/H
2
) in combustion systems is the
dynamics of the sensor signal (Us). As the content of unburned residues increases, so
do the dynamics. Figure 4 below plots the rise of the sensor signal versus the
measured O
2
value in a reference system (12 MW gas combustion) at low load.
small load
700
400
600
300
500
200
100
0
0 3 1
4 2
5 6
2
40
300
O ref. [%]
2
CO
[
p
p
m
]
U [
m
V
]
Se
ns
or
Signal dynamic
> 100 mV
+
Fig. 4: Sensor voltage U
COe
plotted versus the O
2
value of 12MW
gas combustion