Green 01381, Manual, Page: 6 / 48

Introduction
6
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1.3 About the Analyzer
The G36p Oxygen Analyzer continuously measures the content of oxygen with concen-
trations up to 21.0 %. The analyzer can be used to measure the content of oxygen in N2
or CO2 based inert gas, or in stack gas, or in connection with exhaust gas recirculation
(EGR). The G36p Oxygen Analyzer is designed for front panel mounting.
The G36p Oxygen Analyzer uses a zirconia sensor. The zirconium dioxide sensors have
long been established as industry standards. The G36p uses a new type of zirconia sensor,
which can be used in a wide range of applications.
The most important element of
the sensor is the zirconia cell.
At high temperatures, the oxy-
gen ions can diffuse through
the zirconium dioxide mem-
brane. When the membrane is
exposed to environment that
contains different amounts of
oxygen (e.g. the sensor inter-
nal reference gas on one side
and sample gas on the other),
nature seeks to balance itself,
and the transportation of ions
through the membrane will
generate an electrical charge.
Sample Gas
Ambient Air
Zirconium Dioxide Membrane
O
2–
O
2–
ZrO
2
O
2
O
2
O
2
O
2
O
2
O
2
O
2
O
2
O
2
V
e
–
e
–
Figure 1-1: Simplified schematic of the zirconia cell
This charge depends on the amount of the passing oxygen ions i.e. the difference between
the oxygen levels in the sample gas and the reference gas. This voltage will be detected
and converted into a signal that is proportional to the oxygen concentration in the sample