One of the primary advantages of fieldbus is the elimination of customization in your project. What do we mean by customization? It's all the additional work you have to do to get everything to plug in and play together with everything else. The early days of digital process automation were an ugly mess of different proprietary protocols, from proprietary digital protocols at the instrument layer to proprietary control networks at the control backbone, to an even bigger mess of proprietary technologies at the operations management and business layer.
Users can spend more than half of their project costs on activities that can be directly traced to customization. At the field device level, analog technology creates unnecessary work processes because of the lack of direct, bidirectional digital access to devices for commissioning and diagnostics. Instrument engineering alone can account for 20 percent of overall automation project costs. Even if you are using digital devices, customization and proprietary technology at the application and network level meant that much of the data from intelligent devices may not even be accessible, and certainly not easily so, by the people that need it when they need it.
Many of the stringent objections I get from people in the industry regarding fieldbus technology is that many suppliers already have the capability to do some of the things that fieldbus does without fully adopting the technology, so where is the advantage in adopting fieldbus? Eliminating the billions of dollars worth of customization seems to be a good reason. You can have a proprietary digital protocol, a proprietary control network or backhaul network, and proprietary technologies for getting data from one place to another. But what does that add to the installed cost of your application? What does that do to the cost of your solution, from products to services to lifecycle and operational costs, maintenance costs, and more?
That's the catch. While the installed cost of an automation solution may be just a fraction of the total cost of a process automation project (in refineries automation can be less than a percent of overall project costs), the impact of the automation solution on the lifecycle and operational costs of a plant is immense. The automation system is the ultimate factor in plant uptime. It is your window into what is happening in your plant and your process. If you are still relying on technology that is 30 years old, you should rethink your approach.
FOUNDATION technology is an open specification that provides seamless data access from the field all the way up to operations management applications. Supplier products are tested and registered to ensure they conform to this specification. We then take input from end users and evolve our specification based on their functional requirements. It's a level playing field, but suppliers also have the ability add their own specific functionality and expertise on top of the standard solution. Looking at your supplier's fieldbus offerings is a good way to gauge their level of willingness to provide open solutions.