Introducing Reference Gas; Requirements For Reference Gas From The Gas Cylinder; Check The Reference Gas Flow - Siemens SIPROCESS GA700 Quick Start Manual

Commissioning
7.4 Introduction of reference gas
7.4.2

Introducing reference gas

● Set the flow of sample gas and reference gas to the same level.
● Always introduce the reference gas before introducing the sample gas.
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.
7.4.3

Requirements for reference gas from the gas cylinder

The reference gas pressure must be 2 000 hPa above the sample gas pressure for sufficient
measuring ability.
1. Use a reference gas line with the following characteristics at measuring spans of < 2%
oxygen:
– Small cross-section, e.g. pipe diameter 2 mm
– Made of metal, e.g., stainless steel
2. Flush the reference gas line thoroughly with reference gas before commissioning.
7.4.4

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.
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Compact Operating Instructions, 05/2018, A5E31805656-06
Quick Start