Control System Selection – Finding the One That’s Just Right

The process control system (PCS) ties together all the automation elements of a process manufacturing unit and affects every aspect of operations. As the brain and central nervous system of a facility, the level and quality of its performance is key to keeping operations up and running.

As new technology abounds in the automation and control industry, now is the perfect time for manufacturers to modernize their PCS platform to improve efficiency and operational performance. They can innovate – not simply duplicate – the functionality of their existing legacy infrastructure. To this end, manufacturers must carefully select the right PCS and third-party vendor who understands their specific platform requirements and can move them into the modern world.

Set the course

Those individuals responsible for choosing the right PCS and vendor will first need to weigh all system infrastructure options. After all, a good decision will have a positive impact on the facility’s ability to produce effectively and profitably. The operators will find the system “easy to drive,” and there will be room to improve and optimize the process. A bad decision can lead to opposite results.

The assigned project team, which may include outside consultants, should know the challenges inherent in the decision-making process. They must plan early and set a positive course, steering clear of subjective or emotional views based on past experiences and focus on delivering the best solution. Tools and methods exist to help shed more objective light on these types of projects, so groups can make more informed decisions. Teams can then decide based on the specific needs of the facility and process, while considering a variety of critical factors.

Critical requirements

To begin, the team should review what the company makes and how these products are produced. Next, they should specify the elements, or Critical to Quality (CTQ) parameters, that have the greatest effect on quality and efficiency. Key stakeholders (e.g., operators, process engineers, maintenance, production management, and others) involved in the automation project must help determine the CTQ list.

One of the first questions stakeholders should ask is what makes for a “good day” from an operational standpoint, and how does the PCS fit into that picture? The list of CTQ elements should be arranged and categorized with the most important element at the top (Table 1). This approach will help sort out the strengths and weaknesses of each PCS for easy side-by-side comparison.

CRITICAL TO QUALITY ELEMENTSVENDOR AVENDOR BVENDOR CVENDOR D
Has an extensive installed base in our industry3784
Has modules to support APC strategies2568
Supports smart I/O for smart devices and diagnostics5557
Supports high-performance HMIs2645
Easy to add instrumentation4467
Our existing control strategy will transfer well3322
Strong track record of user support5657
TOTAL24363640

Table 1

Once the CTQ elements are listed, the next step is to rank each vendor on its ability to meet each requirement. All items listed will need to be considered for performance both now and in the future, and vendors must be flexible to deal with emerging technology trends. For example, some systems made the move from proprietary platforms to Windows, or serial networks to Ethernet, more easily than others. Such track records can be useful to predict how a vendor will respond to new waves of technology.

A strong vendor selection team can generally compile a good list of CTQs, but most invariably may still miss a variety of critical items. A great deal of practical experience with vendor systems and objectivity is required.

Invaluable knowledge

Very few people working in a process manufacturing facility for any length of time will have participated in more than one major PCS installation or migration project. Due to the infrequent nature of these types of projects, it is no easy task for some project teams. In addition, a PCS vendor may lack experience with some of the project’s site-specific elements.

In these instances, a platform-independent automation solutions partner with a long track record of executing successful PCS installation and migration projects is invaluable. They typically have specialists who have worked with the main vendors being considered and can bring to the team their objectivity, experience and knowledge on the various platforms. Not only can they work with key stakeholders to help outline the CTQ elements and then objectively rate the respective vendors, they can also help with the request for proposal (RFP) process, which can be complex at best.

A PCS installation or migration project is exciting, but it is also a major investment. It requires an enormous amount of work and the risks are high. A poor decision now will remain with a facility for several years or could require great expense to fix. Choose wisely when selecting your next PCS platform and consider the deep bench of experienced people who will help ensure your project is successful in terms of budget, schedule and performance. The right guidance will make sure any decisions made are remembered positively for many years to come.