Calibration World Issue 1-2007 - Beamex - #7

fieldbus calibrator

systems began to make their arrival. The first digital, smart transmitter was introduced in the 1980s, using first proprietary protocols. The first fieldbus was introduced in 1988, and throughout the 1990s a number of various fieldbuses were developed. During the 1990s, manufacturers battled to see whose fieldbus would be the one most commonly used. A standard was finally set in the year 2000 when the IEC61158 standard was approved. The Foundation Fieldbus H1 and the Profibus PA, both used in process instrumentation, were chosen as standards.

For the most part, one can say that the Foundation Fieldbus is dominating the North American markets and the Profibus is the market leader in Europe. Other areas are more divided. There are also certain applications that prefer certain fieldbus installations despite the geographical location.

Future of fieldbus

Currently, a large number of fieldbus installations already exist and the number is increasing at a huge rate. A large portion of newprojects is currently being carried out using fieldbus. Critical applications and hazardous areas have also begun to adopt fieldbus.

The Foundation Fieldbus and Profibus have begun to clearly dominate the fieldbus markets. Both Foundation Fieldbus and Profibus have reached such a large market share that both buses will most likely remain also in the future. The development of new fieldbuses has slowed down and it is unlikely that new fieldbus standards will appear in the near future to challenge the position of Foundation Fieldbus or Profibus.

Recent co-operation between Foundation Fieldbus and Profibus suppliers will further strengthen the position of these two standards.

Fieldbus benefits for industry

Obviously process plants would not start utilizing fieldbus, if it would not offer them benefits compared to alternative systems. One important reason is the better return on investment. Although fieldbus hardware may cost the same as conventional, or even a little bit more, the total installation costs for a fieldbus factory is far less than conventional. This is caused by many reasons, such as reduction in field wiring, lower installation labour cost, less planning/ drawing costs, and no need for conventional I/O subsystems.

Another big advantage is the on-line self-diagnostics that helps in predictive maintenance and eventually reduces the downtime, offering maintenance savings. Remote configuration also helps to support reduced downtime. The improved system performance is important criteria for some plants. There are also other advantages compared to conventional instrumentation.

Fieldbus transmitters must also be calibrated

The main difference between a fieldbus transmitter for pressure or temperature and conventional or HART transmitters is that the output signal is a fully digital fieldbus signal.

The other parts of a fieldbus

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www.beamex.com/calibrationworld CALIBRATION WORLD 01- 2007