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What is Foundation Fieldbus?

Foundation Fieldbus is an all-digital, serial, two-way communications system that serves as a Local Area Network (LAN) for factory/plant instrumentation and control devices. The Fieldbus environment is the base level group of the digital networks in the hierarchy of plant networks. Foundation Fieldbus is used in both process and manufacturing automation applications and has a built-in capability to distribute the control application across the network.
Unlike proprietary network protocols, Foundation Fieldbus is neither owned by any individual company, nor regulated by a single nation or standards body. The Foundation Fieldbus, a not-for-profit organization consisting of more than 100 of the world's leading controls and instrumentation suppliers and end users, controls the technology.
While Foundation Fieldbus retains many of the desirable features of the 4-20 mA analogue system, such as a standardized physical interface to the wire, bus-powered devices on a single wire, and intrinsic safety options, it also offers many other benefits.

Device interoperability Foundation Fieldbus offers interoperability; one Fieldbus device can be replaced by a similar device with added functionality from a different supplier on the same Fieldbus network while maintaining specified operations. This permits users to 'mix and match' field devices and host systems from various suppliers. Individual Fieldbus devices can also transmit and receive multivariable information, and communicate directly with each other over a common Fieldbus, allowing new devices to be added to the Fieldbus without disrupting services.
Enhanced process data
With Foundation Fieldbus, multiple variables from each device can be brought into the plant control system to analyse trends, optimise processes, and generate reports. Access to accurate, high-resolution data enables processes to be fine-tuned for better productivity, less downtime, and higher plant performance.
Overall view of the process
Modern Fieldbus devices, with powerful microprocessor-based communications capabilities, permit process errors to be recognized faster and with greater certainty. As a result, plant operators are notified of abnormal conditions or the need for preventive maintenance, allowing personnel to consider pro-active decisions. Lower operating efficiencies are corrected more quickly, enabling production to rise while raw material costs and regulatory problems fall.
Improved in plant safety
Fieldbus technology helps manufacturing plants keep up with stringent safety requirements. It can provide operators with earlier warning of potential hazardous conditions, thereby allowing corrective action to be taken to reduce unplanned shutdowns. Enhanced plant diagnostic capabilities also offer less frequent access to hazardous areas, thus minimizing the risks to personnel.
Easier predictive maintenance
Enhanced device diagnostics capabilities make it possible to monitor and track insidious conditions such as valve wear and transmitter fouling. Plant personnel are able to perform predictive maintenance without waiting for a scheduled shutdown, thus reducing or even avoiding downtime.
Reduced wiring and maintenance costs
The use of existing wiring and multi-drop connections provides significant savings in network installation costs. This includes reductions in intrinsic safety barriers and cabling costs, particularly in areas where wiring is already in situ.
Additional cost savings can be achieved through the decreased time required for construction and start-up, as well as simplified programming of control and logic functions using software control blocks built into Fieldbus devices.

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