Siemens SIPROCESS GA700, Operating Instructions Manual, Page: 162 / 224

6.3 Field module
6.3.1 Gas connections
Safety instructions
WARNING
Possible leakages of gas path
Fit the gas connections in accordance with the mounting specifications of the manufacturer
using a suitable open-ended wrench. In the process, make sure that you counter properly.
Otherwise, there is a danger that the gas path will leak.
WARNING
Danger of poisoning by escaping gas
Components which come into contact with the sample gas must be resistant to it. Otherwise,
there is a danger that the gas path will leak and that sample gas will accumulate in the
analyzer.
Take appropriate precautions to prevent gas from escaping, e.g. by monitoring the flow
outside the analyzer.
Since it is not possible to absolutely guarantee that toxic or corrosive gases cannot escape
from or accumulate in the enclosure - even if to a limited extent - the field module must be
purged with oil-free and dry purging air (e.g. from the non-hazardous area) or with inert gas
when measuring corrosive or toxic gases.
Calculation of the required purging gas flow must be carried out by a technical expert. The
discharged purging air must be disposed of environmentally-friendly via a suitable exhaust
line.
An additional flame arrester to which the exhaust line is connected must be provided in this
case in addition to the pressure compensation connection.
Note
Reference gas connection
The reference gas connection is designed as a flame arrester. The gas supply is via a 6 mm
pipe, and the connection is made using a clamping ring.
Only use nitrogen as the reference gas.
Wiring
6.3 Field module
Field device
50
Operating Instructions, 05/2015, A5E35640463-02