Sensonic 4000
5
CONSTRUCTION
Picture (page 50) shows a block diagram of the
Sensonic 4000
.
Here is a description of the individual components.
5.1
Elements of gas circuit
5.1.1
Gas probe with in-line filter
The gas probe is used to extract the gases under investigation and to measure their temperature. The gas
probe consists of two parts, the probe pipe with thermocouple (1) and the probe holder (2).
Picture 1 Gas probe with in-line filter
The probe pipe is typically supplies in one of four standard lengths: 150 mm, 300 mm, 750 mm and 1500
mm. As standard a Ni-CrNi thermocouple is used. The probe pipe is fitted with an anchor cone to simplify
fixation in the flue gas channel.
The probe pipe is attached to the probe holder with a threaded connector.
The gas tubing in the
Sensonic 4000
is protected from the dust and moisture present in the flue gases by a
filter (4). The filter elements (3) should be changed when dirty to ensure a free flow of gas. The condensate
should be removed from the condensate traps when necessary.
The plug (6) and hose end (5) are connected to the front plate of the analyser.
5.1.2
Gas pump
The internal gas pump draws the gas into the
Sensonic 4000
and passes it through the gas chambers. The
self-cleaning pump is a high quality item and is known to be extremely reliable.
The gas cells operate best with a flow rate of 90 l/h, which is set at the factory and compensates
automatically for flow restrictions or changes in battery voltage.
5.1.3
Gas chamber
The gas chamber is fitted with between two and six gas sensors. Oxygen and carbon monoxide sensors are
fitted as standard equipment. The other cells are chosen when the instrument is ordered. The gas chamber of
the
Sensonic 4000
system is characterised by minimal dead capacity, which leads to low inertia of the
analyser indications. In addition to the gas sensors, there is a temperature sensor placed in the chamber for
temperature compensation of the sensors.
