Dräger Polytron 5200, Инструкция по эксплуатации

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Sensor principle
Dräger Polytron 5200 / Dräger Polytron 53X0 23
6 Sensor principle
6.1 Operating principle for
DrägerSensor DD, LC
The DrägerSensor is a transducer for measuring the partial
pressure of combustible gases and vapors contained in ambi-
ent air. It uses the heat-of-combustion principle.
The monitored air diffuses through the sintered metal disc into
the sensor. The mixture of combustible gases and vapors are
catalytically combusted at a heated detector element (pelli-
stor). The monitored air supplies the Oxygen required for the
combustion (must be greater than 12 Vol%). Due to the result-
ing heat-of-combustion, the detector element gets hotter. This
increase in heat causes a change of resistance in the detector
element, which is proportional to the concentration of the mix-
ture of combustible gases and vapors in the monitored air.
In addition to the catalytically active detector element, there is
an compensator element. Both elements are parts of a Wheat-
stone bridge. Thus environmental effects like changes in tem-
perature or humidity are almost entirely compensated.
6.2 Operating principle for
DrägerSensor DSIR
The DrägerSensor IR infrared gas sensor is a gas transmitter
designed to determine the concentration of gases and vapors
in the ambient air. The principle of measurement is based on
the concentration-dependent absorption of infrared radiation in
measured gases.
The monitored ambient air diffuses through sintered material
into the flameproof housing of a measuring cuvette. The broad-
band light emitted by the radiator passes through the gas in the
cuvette and is reflected by the cuvette walls from where it is di-
rected towards the inlet window of a dual element detector.
One channel of the detector measures the gas-dependent light
transmission of the cuvette (measuring channel), the other
channel is used as reference. The ratio between measuring
and reference signal is used to determine the gas concentra-
tion in the cuvette. The cuvette is heated to avoid condensation
of the atmosphere’s moisture content.
Internal electronics and software are used to calculate the con-
centration. As an output signal, the gas sensor emulates the
half bridge of a catalytic bead sensor.
6.3 Contaminating gases for
DrägerSensor DD, LC
A calibration check might be necessary, if the sensor was ex-
posed to a high concentration of combustible gases or vapors
for an extended period of time or to contaminants as listed
above.
7 Disposing of the instrument
Disposing of electric and electronic equipment:
NOTICE
Certain substances in the atmosphere to be monitored
may impair the sensitivity of the sensors which are in-
stalled in the sensing heads:
a) polymerizing substances such as acrylonitrile, buta-
diene and styrene,
b) corrosive compounds such as halogenated hydro-
carbons (releasing halogens such as bromine, chlor-
ine or fluorine when being oxidized) and halogen hy-
dride acids as well as acidic gaseous compounds such
as sulphur dioxide and nitrogen oxides,
c) catalyst poisons such as sulphurous and phospho-
rous compounds, silicon compounds (especially
silicones), and metal-organic vapors. The sensors
used are based on measuring elements (pellistors)
which are “poison-resistant” (PR) and so have a longer
lifetime than conventional sensors if catalyst poisons
occur.
EC-wide regulations for the disposal of electric and
electronic appliances which have been defined in the
EC Directive 2002/96/EC and in national laws have
been effective since August 2005 and apply to this
instrument.
Special collecting and recycling options have been
established for households. However, as this
instrument has not been registered for household
usage, it must not be disposed of through these
means. The instrument can be returned to your
national Dräger Sales Organization for disposal.
Please do not hesitate to contact the above if you have
any further questions on this issue.
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