Oxygen Monitor SGM7.2 6 Construction
The measuring cell (sensor) consists of a tube made of
zirconium dioxide (2/1) with two platinum electrode. The
measuring electrode is inside the tube (2/3). The reference
electrode (2/4) is located at the outer side of the tube. It
has a constant electrode potential regarding the
surrounding air. The measuring gas is flowing through the
ceramic tube. The electrodes and the ceramic tube form a
galvanic solid electrolyte measuring cell.
Measuring Cell
(Sensor)
To gain a higher oxide ion conductivity of the zirconium
dioxide tube the sensor is heated to 750°C. This also
avoids interfering reactions with combustible components
of the measuring gas at the electrode due to chemical
unbalances. A thermocouple (2/5) inside the measuring cell
determines the actual electrode temperature. A heater
control assures a constant temperature.
Sensor Heater
The heated measuring cell produces warmth energy.
Therefore the SGM7.2 must not covered.
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