The remote terminal units are mounted directly outdoor in the harsh environment of the gas or liquid pipelines and manages both the gas/liquid transmission and storage facilities. The system is designed for installation in hazardous area Zone 2 and has operating temperature of -40°C to 70°C. The product is built to meet ISA’s stringent G3 corrosion resistance requirements and provides an extremely cost-effective, intrinsic safety solution, since it integrates intrinsic safety and sensor signal conditioning into one package, replacing today’s common solution of separate barriers and signal conditioning systems.
All signal runs can be terminated locally and information is passed back to the host system over the open network. Communication from RTUs installed over the length of pipeline provided by fiberoptic or wireless RF signal transmission system (provided by others).
The design of RTUs included in this projectis a completely modular I/O solution for both general purpose and hazardous area applications. Based upon a carrier system that supports a range of modules, it offers a wide variety of I/O functions, including AC mains and intrinsic safety signals – even within the same node. It has an “open” architecture that allows communication with a variety of different field-buses by selecting the appropriate type of Bus Interface Module (BIM).
The system architecture could be based on TCP/IP, Modbus, Profibus or Fieldbus Foundation which is an all-digital, serial, two-way communications system that serves as a Local Area Network (LAN) for pipeline field instrumentation and control devices. The fieldbus environment is the base level group of the digital networks in the hierarchy of plant networks and has a built-in capability to distribute the control application across the network.
The RTUs are dedicated for the requirements of pipeline and process plant owners & operators, contracting engineers, systems integrators who supply or manage pipelines, tank farms and product distribution terminals. The system is based on field mounting process I/O platform that provides installation cost savings through reduced field wiring enabled by a design rugged enough to survive installation in harsh and hazardous locations. Process I/O delivers to the user diagnostics, fault management and information integrity expected of a traditional DCS product.