FOUNDATION™ fieldbus FAQ'S

Display instrumentation for use in hazardous and safe areas

Many basic questions about FOUNDATION™ fieldbus have already been answered. Perhaps yours is one? Check below to find out. If you can't find an answer, please contact us and we will do our utmost to help.

The FOUNDATION™ fieldbus solution is a systemic technology comprised of a bi-directional communications protocol used for communications among field devices and to the control system. It uses a Function Block structure for true distributed control and Device Description (DD) technology for parameterisation and integration of data via a network hierarchy for subsystem integration and a well-defined system management structure for reliability and determinism of functional execution.

Yes. The Fieldbus Foundation registers a wide range of FF-compliant products from transmitters and meters to valve positioners, actuators, controllers and linking devices. These products are available from a wide variety of the world's leading automation equipment suppliers. The online product catalogue (fieldcommgroup.org) gives registered device information including which standard blocks were tested for interoperability, the presence of untested Function Blocks (if any) and additional useful information about the device.

The H1 Fieldbus is a bi-directional communications protocol used for communications among field devices and to the control system.

From a business viewpoint FF technology delivers savings in total installation costs. H1 Fieldbus reduces instrument wiring which in turn means less termination and fewer screwdriver turns. The technology reduces hardware requirements and lowers capital expenditures (CAPEX) whilst it also reduces operating expenses (OPEX) through improved plant efficiencies, better asset management and reduced maintenance requirements.

Specific benefits of Fieldbus technologies include reduced wiring; multi-variable information via a single multi-channel field instrument; simpler integration and easier maintenance. Ultimately, Fieldbus technology will be the key to greater manufacturing flexibility and productivity, higher quality products and improved regulatory compliance. This can be achieved by predictive maintenance scheduling and better upkeep via the embedded diagnostics, performance analysis data and operational statistics. Properly adjusted and calibrated devices ensure lower process variability and higher plant availability.

The isochronous bus cycle enables tighter loop tuning and as a result, better process control. Firmware download gives the ability to stave off obsolescence, giving Fieldbus plants longer life than other plants, with greater ease.

FF H1 is the only digital Fieldbus protocol developed to fully meet with the original IEC 61158 requirements. Unlike other protocols, H1 provides explicit synchronisation of control and communication for precisely periodic (isochronous) communication and execution of control functions with minimised dead time and jitter. It synchronises clocks in Fieldbus devices for support of Function Block scheduling and alarm time-stamping at the point of detection.

Additionally, H1 provides automatic address setting, eliminating the need to manually set addresses off-line using a tool or DIP switches and avoiding subsequent mistakes. H1 also uses peer-to-peer communication where devices communicate directly using a publisher/subscriber communication relationship, enabling data to be sent to several devices in a single message and thus reducing system overhead. H1 includes alarm and event reporting for efficient diagnostics and process alarms, whilst online firmware downloads make it possible to upgrade devices in order to stay ahead of the obsolescence curve. Lastly, a rigorous interoperability-testing program ensures connectivity problems are minimised.

H1 has made it possible to "mine" important information from the plant floor. When used correctly, this information empowers operators and technicians to make plant operation and maintenance easier. Some end users report commissioning time savings as high as 75% compared with conventional analogue technology by switching to Fieldbus technology.

FOUNDATION technology enables improved asset management using device management software, as many failures can be predicted and faults can be diagnosed in detail. Together, device management software and Fieldbus devices typically enable:

  • Identification & information
  • Diagnostics, performance analysis & operational statistics
  • Parameterisation, ranging, reconciliation & audit trail
  • Simulation & override
  • Calibration trim & log
  • Document access
  • Device event capture & monitoring
  • Commissioning
  • Maintenance log & service notes
  • Device listing
  • Maintenance & calibration scheduling

H1 was designed specifically for process automation. It differs significantly from device-level networks for factory automation in its ability to provide intrinsically safe power for field devices used in hazardous locations. Moreover, thanks to scheduling, H1 Fieldbus is isochronous, which is a requirement for continuous regulatory process control.

H1 was designed and developed as a system technology providing significantly more structure and benefit than mere communication networks. H1 technology delivers true distributed control networking and provides asset optimisation through a broad range of diagnostic capabilities and consistent data structures through the use of Electronic Device Description Language (EDDL). FF technology also provides easy and extensive integration capabilities through open and consistent integration to HSE in a single engineering environment. Device-level networks without power and intrinsic safety (and no scheduling) are mostly appropriate for on/off components with limited data and for dedicated applications such as machine control.

FOUNDATION High Speed Ethernet (HSE) is a control network technology specifically designed for process automation to connect higher-level devices such as controllers and remote-I/O, high-density data generators etc., and for horizontal integration of subsystems.

FOUNDATION HSE enjoys a fully fledged redundancy scheme giving control systems greater availability than systems using simple ring-topology. Use of unmodified Ethernet and standard IP makes HSE systems more cost-effective than other Ethernet solutions and proprietary networks. Since HSE is a standard, it enables simple and tight integration between package units and the main control system. The HSE network is easier and cheaper to manage based on common network knowledge and standard SNMP tools.

FOUNDATION HSE is based on unmodified IEEE 802.3 Ethernet and is therefore compatible with standard Ethernet equipment. Unlike "ring topology" FOUNDATION HSE provides complete "DCS style" redundancy with redundant network switches, redundant devices and redundant communication ports ensuring unsurpassed availability. FOUNDATION HSE is also based on standard IP, enabling it to coexist with other devices and ensuring compatibility with standard tools. At the highest level, FOUNDATION HSE includes a standard application layer that provides interoperability between devices beyond the mere coexistence provided by Ethernet and TCP/IP. FOUNDATION HSE communication is schedule-driven to minimise dead-time and jitter with support for peer-to-peer communication directly between devices. Again, a rigorous interoperability testing program ensures minimum connectivity issues.

The hub-and-spoke tree topology of Ethernet makes it very easy to add and remove devices without upsetting the operating network. Because FOUNDATION HSE is based on unmodified Ethernet, standard Ethernet tools can be used for installation qualification, testing and troubleshooting. These tools speed up the resolution of communication problems. FOUNDATION HSE is supported by troubleshooting tools that are not available for RS485 or coax, and since FOUNDATION HSE is based on UDP and TCP, standard network management tools employing SNMP, RMON, etc., can also be used. Similarly, familiar IP addressing is used including support for DHCP.

Interoperability is made possible by the fact that devices and software are conforming to the same standard. Testing and registration ensures that Fieldbus devices bearing the official "checkmark" seal can be connected on the same bus or network and exchange information without significant integration effort. End users can select the best device for a specific measurement or control task, regardless of the manufacturer. A current list of registered products is available on the FF website (fieldcommgroup.org).

Interoperability refers to the ability of any ITK-registered device to work with any HIST-analysed host. Users want to operate their entire plant from one operator interface and maintain all devices on the system with one maintenance application.

Yes. End users can substitute a registered Fieldbus device from one manufacturer with that of another manufacturer on their network without loss of degree of integration.

Fieldbus technology is now being utilised on automation projects of all sizes, including both new and retrofit installations. According to an ARC Advisory Group survey, a significant number of end users are installing small, medium and even very large Fieldbus systems consisting of over 2,000 I/O points. Shell, a major adopter of FF technology, reportedly has over 120,000 installed Fieldbus I/O with 31% of these devices replacing conventional instruments.

Both H1 and HSE were specifically designed for process control. Because H1 and HSE have complementary characteristics covering diverse networking needs, Fiedlbus technology is appropriate for many applications. These include closed-loop continuous control, batch sequencing, remote-I/O and legacy system integration. The Fieldbus Foundation's Safety Instrumented Systems (SIS) specification includes an additional safety layer based on IEC 61508 requirements, making it suitable for use in plant safety systems.

The Fieldbus Foundation established an End User Advisory Council (EUAC) to give end users a voice in the direction of its technology. The group meets two to three times per year to discuss issues involving their specific plants and industries.

Yes. A key tenet of both the Fieldbus Foundation and PROFIBUS protocols is that they are non-proprietary and available to all companies wishing to include it in their product offerings. Both the H1 Fieldbus and the HSE control network are part of the IEC 61158 protocol standard and IEC 61784 profile.

Yes. FF technology provides end users with the freedom to locate control in the control system or in the field devices. The Fieldbus Foundation does not advocate a particular control strategy.

FOUNDATION HSE enables information from intelligent devices to pass through control systems without loss, degradation or the delay associated with proprietary control networks to device management software. It also allows the possibility of electronic integration with higher-level MIS and ERP applications.

Fieldbus Foundation members provide a variety of discrete devices for mini remote I/O, relay, on/off valves, valve couplers, electric actuators, etc., on H1 as well as large remote I/O on HSE. Indeed, on/off signals in bulk are an integral part of the FOUNDATION solution. The technology is well suited for hybrid control.

The IEC voted to include the FOUNDATION HI and HSE specifications in the IEC 61158 international Fieldbus standard. The CENELEC Technical Bureau added the FOUNDATION H1 specifications to EN 50170, the Fieldbus Euronorm. In addition, FOUNDATION technology is the only implementation of the ANSI/ISA-50.02 standard.

Both NAMUR (Germany) and JEMIMA (Japan) have voiced support for FOUNDATION technology, and provided input from the end user community that aided in specification development. Approval and support by key international industry bodies gives confidence to users that their investments in FOUNDATION solutions are based on recognised global standards.