PROFIBUS is unique in offering a fully integrated solution for fieldbus in both discrete and process applications.

PROFIBUS DP is the profile for discrete (or factory) automation. An identical protocol, profiled as PROFIBUS PA, is used for process automation.

From the diagram you’ll see the single cable (the blue line) carrying communications between a controlling device (indicated as ‘DCS’, but it can also be a PLC or a PC) and individual IO devices. Above the blue line are typical factory devices controlled using PROFIBUS DP. Typical process layouts using PROFIBUS PA are indicated below the blue line as ‘segments’ of control.

THE 'HYBRID' FACTOR

Many process plants involve ‘hazardous areas’ so process networks have to use special physical connections. This is what differentiates PROFIBUS DP and PROFIBUS PA.

However, process plants often include discrete functions so the common protocols of PROFIBUS DP and PA deliver a powerful advantage – both process and factory automation networks can be connected to the same single cable. Other fieldbuses focus on either process or discrete markets so they always have to use a second fieldbus, which means extra expense for cabling, equipment, skills, maintenance and support. 

PROFIBUS is alone in delivering a single solution for both sectors.

THE VALUE PROPOSITION

The value proposition of PROFIBUS is commandingly high, enabling it to cut costs and improve business results across the life cycle of a plant. It does this in many ways:

• At the engineering stage it simplifies plant design, eliminates hard wiring and requires less hardware, leading to faster commissioning and lowered costs.
• It supports better diagnostics, so commissioning is much faster.
• It helps achieve better productivity and higher product quality through the delivery of better and more timely data to operations and management staff.
• It supports advanced asset management strategies that allow plants and equipment to be better managed and maintained.

By the end of 2008 nearly 30,000,000 PROFIBUS devices were in use and this figure is expected to rise to 50,000,000 by 2012.

The huge number of vendor companies which have developed PROFIBUS devices for both discrete and process automation markets ensures that system integrators and end users have massive choice ... and that means security and flexibility of supply as well as healthy competition amongst vendors.