Field Module; Gas Connections - Siemens SIPROCESS GA700 Operating Instructions Manual

6.3

Field module

6.3.1

Gas connections

Safety instructions
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.
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.
Note
Shutting off the sample gas inlet and outlet
If you shut off the sample gas inlet and outlet, make sure that the reference gas can escape, for
example, by a 2-way valve at the sample gas outlet.
Do not switch off the reference gas! Aggressive sample gases can destroy the microflow sensor.
Field device
Operating Instructions, 05/2022, A5E35640463-07
WARNING
WARNING
Wiring
6.3 Field module
41