PI extract denotes Profisafe as leading technology

Profisafe is currently regarded as the global market leader with more than 630,000 Profisafe nodes, according to an extract in an article from Profibus International (PI).

The extract, 'Safety in a new way' by Dr Peter Wenzel, said that 10 years ago, however, it was necessary to convince safety authorities, 25 renowned safety engineering companies and users to accept the new technology.

Arguably, an idea has seldom achieved acceptance on the market so quickly as that behind safety-related communication via Profisafe.

A decade ago, users nor manufacturers, let alone testing laboratories, could imagine that safe communication over a fieldbus was possible.

Profibus, the only fieldbus with an integrated solution for all areas of production and process automation, was already established and in widespread use.

However, when it came to matters of safety, the prevailing opinion was that safety engineering required hard-wired solutions based on relay technology and few innovations were attempted.

The advantage of traditional safety engineering was its simplicity.

Still, little by little, the disadvantages of this method for meeting the requirements of modern automation became evident.

These included, for instance, the costs for labour-intensive cabling, the low degree of flexibility and availability and the significant effort required for restart after a stop as a result of the undefined stop positions of machines.

An inquiry from a large petrochemical company was destined to change the safety engineering world, according to the article.

Herbert Barthel, head of the PI functional safety working group, said: 'We were asked whether it was conceivable that safety-related functions could be transmitted over a fieldbus.

In the world of production and process automation, this had been unimaginable.

Dr Wolfgang Stripf, who has overall responsibility for functional safety and data security within the Technical Committee 3 of PI, said: 'At the time, there were proprietary solutions in rail engineering, but these could not be transferred without additional work.

Unlike that industry, the two automation experts wanted an open technology that would be accepted by all manufacturers and users.

At the same time, the safety institutions and testing laboratories would have to be brought on board.

Thereupon, in September 1998, a roundtable of 25 renowned safety companies was created.

Back to top