Check The Reference Gas Flow; Reference Gas Monitoring With Pressure Switch - Siemens SIPROCESS GA700 Operating Instructions Manual

Note
Introduction of the reference gas during measurement interruptions
In the case of temporary interruption of the measurements, keep introducing the reference gas
into the analyzer module. In this way, the sample gas remaining in the sample chamber is
prevented from diffusing to the microflow sensors and possibly destroying them.
9.4.4

Check the reference gas flow

Procedure
1. Close the sample gas inlet.
2. Lay a hose with an internal diameter of 4 mm from the sample gas outlet into a beaker filled
with water.
3. Apply reference gas to the analyzer module.
The reference gas must exit slowly with 1 to 2 bubbles per second through the water filling (at
versions with flow-type compensation circuit, 2 to 4 bubbles per second). The reference gas
flow rate is then sufficient.
9.4.5

Reference gas monitoring with pressure switch

Note
No monitoring of measuring ability
The reference gas pressure switch only has a protective function for microflow sensors and is not
intended to monitor the measuring ability.
It only monitors that the reference gas pressure is at least 1 000 hPa above the sample gas
pressure.
Note
Excessive sample gas pressure
At the time of delivery, the pressure switch for reference gas monitoring is set to approx.
2000 hPa (rel.). If you need to change the sample gas pressure by more than ±150 hPa due to
process-specific requirements, you should also change the reference gas pressure by the same
amount. Only then is sufficient monitoring functionality of the pressure switch ensured.
To reset the pressure switching point of the reference gas pressure switch
• Contact the Service (Page 149).
• Have the pressure switching point of the reference gas pressure switch adjusted by a Siemens
technician or someone trained for this scenario.
Rack-mounted device
Operating Instructions, A5E31874006-12
9.4 OXYMAT 7 / ULTRAMAT 7: Introduction of reference gas
Commissioning
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