Emerson Process Management ControlWave XFC - Manual (Page 133)

CI-ControlWave XFC Appendix F / F- 31
executed to calculate standard compressibility Zs for the defined gas composition. The
calculation of Zs will be done once per minute or whenever a related gas constant changes.
Users may select which Supercompressibility equation to use on a per run basis. The user
will click on the appropriate button to select the calculation equation to be used. The
selected compressibility calculation will be shown.
When using the AGA8 Gross Calculation, the user must select the Gross Mode1 or the
Gross Mode2 calculation. The user may change the Base Pressure and the Base
Temperature for this screen.
Flowing Static Pressure, Flowing Temperature, BTU and Specific Gravity in use are
displayed on this page.
Values of the gas components used to calculate the Supercompressibility are displayed
along with the FPV, Zflowing and ZBase values calculated by the Supercompressibility
equation in use.
F.7 CHROMATOGRAPH CATEGORY FUNCTIONS
The standard application program is configured for communicating with a Daniel 2251 Gas
Chromatograph, via a serial MODBUS interface. Users will configure the Chromatograph
interface from the “Chromatograph Setup” Web Page (Figure F-21).
Figure F-21 - Chromatograph Setup Web Page
F.7.1 Communication Settings
Mode – Enabled/Disabled - When this signal is ENABLED, a chromatograph is present,
and gas component data is provided by the chromatograph interface. When this signal is
DISABLED, the fixed values for the gas component data are used.