Huade Petrochemical SCADA System:

For the past 16 years, TRC has completed multiple SCADA projects for the Huade Petrochemical Company. The site is located just west of Hong Kong and comprises of a Crude Oil loading and storage facility. The projects include: Head Station's Docking and Tank Farm Control System, Pipeline Control System, On-Shore Tank Farm Expansion, Mid-Station Control System, Re-Distribution System, etc. The SCADA Systems are all based on AB PLC5 and Rockwell ControlLogix PLCs with redundant DH+ and CNET networks.

In the most recent project TRC integrated the entire pipeline control system into the newly built On-Shore Control System, and integrated a Leak Detection System as well. The completed system allows Huade's operator to control and monitor the entire pipeline facility remotely, while the system will have enough reserve capacity for the upcoming tank farm expansion project.


Beijing Airport Natural Gas Pipeline SCADA System

On November 27, 2000, TRC was awarded a turnkey SCADA project for the Beijing International Airport Gas Distribution and Control System. The natural gas pipeline supplies gas to the entire airport facility, in addition to the associated residential area for all airport staff. The gas has two sources, Huabei gas/oil field and Shan Ganning gas field.

The system was designed to replace the old manual system with a new automatic monitoring and control system. The design was implemented jointly by Beijing Gas Department and TRC, in association with TRC’s local branch in China; Boyang Technologies Inc. Boyang staff was also utilized to install all end devices and perform loop testing. The SCADA system consists of three different parts, MCC (Major Control Center), MVC (Major View Center) and the Field. The MCC is the center of operation; it gathers the real time data via PSTN, shows the data on the operation screen, and logs the data onto the Industrial SQL Server. The MVC is principally used by the management department located 2 miles away from the MCC; it has two view only workstations and is interfaced with the Management Department MIS system. The Field includes 3 major distribution stations and 14 remote metering stations; all configured with RTUs These RTUs receive data from the pipeline and forward it to the MCC. The MCC is configured with a redundant real time server and a single Industrial SQL Server. The real time servers utilize the Wonderware INTOUCH graphical user interface for monitoring, remote control, alarming, trending and other SCADA functions. The 2 real time servers have synchronization of system time, database, alarms, etc, i.e. a true hot backup redundant system. The switch over time upon server failure is 5 seconds. Wonderware’s Industrial SQL is used to log all the historical data, provide real time trending, reporting, system events, and functions as a standard interface with other systems, such as MIS.

The MVC workstations use INTOUCH view-only licenses. They are configured as a read only system, utilizing remote reference to access real time data from the MCC. The MVC application itself does not have a local database, the current data values monitored on the screen are from the MCC real time servers, and the historical data is accessed from the MCC Industrial SQL server. The communication between MVC and MCC is ISDN.

Control Microsystems SCADAPACK RTU's are utilized in the Field. The RTU's are installed in each station’s local control room and communicate via PSTN to the MCC. Communications between the Field and MCC utilizes the Industry Standard MODBUS Protocol, modified by TRC for report-by-exception. TRC was responsible for the detailed system design, procurement, system configuration and software development, system integration and testing, installation supervision and start-up.


Huaneng-Amoco Clean Energy Company LtdShanghai, China LPG SCADA System

In January 1997, Amoco awarded a contract to Praxis for the implementation of a SCADA system for their LPG terminal facility near Shanghai, operated by the Huaneng-Amoco Joint- Venture. The LPG is imported from Middle-East by ship, and is stored in 3 spherical tanks. The LPG is than processed and distributed to industrial users via a pipeline network. The SCADA system contains 4 different sub-systems, a main control system, an ESD system, a fire system and docking system. Each system has its own PLC, except for the docking system. All other systems are installed in the central control room with the Master Workstation. The docking system is installed in the docking area, connected with the central control room via a fiber optic cable.

The main control system monitors all current data from the field, including local I/Os and the data from other systems. The ESD system controls the operation of shut down Valves, Pumps and Compressors based on the cause and effect ESD design conditions. The Fire system monitors the heat and smoke detection system installed in the operational area, and sends alarm commands to the ESD system. The Docking system control the Docking area’s compressor based on the pipeline temperature, and maintains the LPG temperature before it is pumped into the storage tanks.

Operators control the system via two workstations located in the central control room. These two workstations utilize Wonderware InTouch5.6b graphical user interface for monitoring, remote control, alarming, trending and other SCADA functions.

All 4 PLC systems are implemented with Modicon Quantum PLC 21300 series, and all PLCs are connected via a Modbus Plus network to the two Operator Work Stations.

Praxis was responsible for the detailed system design, system configuration and software development, system integration and testing, installation supervision and start-up.