Maintenance
FLOWSIC600 · Technical Information · 8010125 V 4.0 · © SICK AG
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6.2
Routine checks
The information displayed on the front panel LCD display of the FLOWSIC600 meter can be
checked to ensure that the system is functioning properly. The MEPAFLOW600 CBM soft-
ware provides a more user friendly way for doing routine checks.
6.2.1
Comparing theoretical and measured Speed of Sound (SOS)
One of the most important criteria for the correct operation of an ultrasonic gas meter is
the consistency between the theoretical SOS, calculated for the actual gas composition,
temperature and pressure, and the SOS measured by the ultrasonic gas meter.
The Speed of Sound Calculator (SOS Calculator) available in MEPAFLOW600 CBM
calculates a theoretical SOS for a specific gas composition at a specified temperature and
pressure (
). The calculation of thermodynamic properties is based on the "GERG-
2004 XT08 Wide-Range Equation of State for Natural Gases and other Mixtures". The
algorithms that are implemented in the SOS calculator were developed by the Ruhr-
University Bochum (Germany).
Figure 79
Speed of Sound Calculator with loaded gas composition file
Use MEPAFLOW600 CBM to connect to the meter (
).
Start the SOS calculator from the Maintenance Report or choose "Tools / SOS
Calculator" from the menu (