Sixnet IPms for AGA gas-flow calculations
Sixnet has created AGA-3 orifice plate and AGA-7 turbine-meter flow measurement calculations that can be added to any Sixnet IPm RTU controller. This add-on application is ideal for anyone who needs gas flow calculations as part of a flexible SCADA or control application or needs a flow computer with secure Ethernet or Internet access.
The new add-on will totalize transferred volumes based on calculated flow. The gas density input required for AGA-3 and AGA-7 flow calculations can be provided either by AGA-8 gas density calculations or by an external density transmitter connected to an analog input channel. AGA-8 algorithms are implemented as part of the run-time software in the IPm.
The gas composition data required by the AGA-8 gas density energy calculations is entered by means of the configuration software. Or the run-time software can be configured to obtain the gas composition data directly from an external gas chromatograph connected to the IPm. The communications between the IPm and the optional external gas chromatograph is via the Modbus protocol.
All input measured data required for calculations, as well as calculations results are available through the IPm I/O database. This means that flow computer data can be referenced by all other applications in the IPm, including: IsaGraf IEC-61131 programming, Sixlog Datalogging, I/O transfers, Modbus/HART/DNP3 protocol-drivers, and third-party add-on applications.
— Richard Phelps, senior editor, Control Engineering