Siemens SIPROCESS GA700 Kompaktbetriebsanleitung Seite 155

Connect the gas lines to the corresponding inlets/outlets.
Sample gases
When measuring toxic or corrosive gases, the gas path may start to leak and sample gas can
accumulate in the device. This means devices used in hazardous areas must be purged with
air or inert gas. The gas discharged by purging must be routed via an exhaust gas line for
environmentally-friendly disposal.
Explosion hazard
So that you can introduce combustible and/or occasionally explosive media, you must install
suitable flame arresters in the sample gas and reference gas paths directly at the device.
For restricted breathing devices (Ex nR) and for devices which are approved for use in
explosive dust atmospheres: Do not introduce gases which have toxic, corrosive or flammable
components in potentially dangerous concentrations.
Analyzers provided with heating must always be purged when using with corrosive gases.
Gas preparation
The sample gas must be sufficiently conditioned to prevent contamination of the parts through
which it flows. We recommend the following minimum configuration:
● Gas sampling device with filter
● Sample gas cooler
● Analyzer filter, medium pore size <10 µm
Depending on the characteristics of the sample gas it may be necessary to provide additional
equipment, for example, an external gas suction pump, washing bottle or pressure reducer.
Appropriate components must be used for toxic and/or flammable gases. These components
must be approved for the respective application.
Common exhaust gas line
If you wish to exit the sample gas into a common exhaust gas line, observe the following points:
● The exhaust gas line must be free of "rapid" pressure fluctuations. If such pressure
fluctuations are present, implement appropriate remedial measures:
– Install a special exhaust line.
– Alternatively: Install a damping vessel (> 1 l) between the device and the exhaust line.
● Water can condensate in the exhaust line. Therefore, install the exhaust line as vertical as
possible.
Devices in explosion-proof design
Compact Operating Instructions, 05/2015, A5E35134047-02
WARNING
Connecting
4.3 Gas connections
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