is an open, integrated total architecture for information integration. FOUNDATION fieldbus is an all-digital, serial, two-way communication system. H1 (31.25 kbit/s) interconnects field equipment such as sensors, actuators and I/O. HSE (100 Mbit/s) High Speed Ethernet provides integration of high speed controllers (such as PLCs), H1 subsystems (via a linking device), data servers and workstations.
FOUNDATION fieldbus is the only protocol with the built-in capability to distribute the control application across the network. Management Information Systems (MIS), Enterprise Resource Planning (ERP), and Human Machine Interface (HMI) packages access the fieldbus information via the data services.
The H1 fieldbus retains and optimizes the desirable features of the 4-20 milliampere (mA) analog system such as:
- single loop integrity
- a standardized physical interface to the wire
- bus-powered devices on a single wire pair
- intrinsic safety options
In addition, FOUNDATION fieldbus enables:
- increased capabilities due to full digital communications
- reduced wiring and wire terminations due to multiple devices on one wire
- increased selection of suppliers due to interoperability
- reduced loading on control room equipment due to distribution of control and input/output functions to field devices
- connection to the HSE backbone for larger systems
The fieldbus allows multiple variables from each device to be brought into the control system for archival, trend analysis, process optimization studies, report generation, predictive maintenance and asset management. The high resolution and distortion-free characteristics of digital communications enables improved control capability which can increase product yields.
The self-test and communication capabilities of microprocessor-based fieldbus devices help reduce downtime and improve plant safety. Upon detection of abnormal conditions or the need for preventive maintenance, plant operations and maintenance personnel can be notified. This allows corrective action to be initiated quickly and safely.
FOUNDATION fieldbus uses standard function blocks to implement the control strategy. Function Blocks are standardized automation functions. Many control system functions such as analog input AI, analog output AO and Proportional/Integral/Derivative PID control may be performed by the field device through the use of Function Blocks.
The consistent, block-oriented design of function blocks allows distribution of functions in field devices from different manufacturers in an integrated and seamless manner, thus reducing risk of system failure. Distribution of control into the field devices can reduce the amount of I/O and control equipment needed, including card files, cabinets, and power supplies.