Process Control Systems Migrations

July 1, 2005
Control system migration is a primary issue among many automation users today. Few new plants are being built, and capital expenditures continue to shrink.

With the increased focus on return on assets (ROA) and Operational Excellence (OpX), users must find ways to effectively migrate from one generation of control system to the next, whether it is from the installed supplier or a competitor. Suppliers are offering an increasingly varied range of migration options for users to choose from. Users must develop a migration strategy that supports their business requirements.

Process Automation Systems (PASs) have evolved through three generations—central with centralized intelligence; distributed with distributed intelligence at many nodes; and collaborative with intelligence existing at all nodes. Each step has triggered the need to consider migrating to the new generation to capitalize on enhanced functionality and robustness. We have reached a crossroads where it is time to consider whether the business possibilities presented by Collaborative Manufacturing warrant migration to a Collaborative Process Automation System (CPAS). This question is getting more emphasis because all of the major control system suppliers are publicizing their unique versions of CPAS. Meanwhile, ARC estimates that there is roughly $65 billion worth of automation systems installed today that are at the end of their traditional lifecycles.

With so many older systems installed and so many new ones emerging, control system migration strategies are becoming important considerations for enabling increased plant performance and the adoption of new automation strategies. Migration is a critical step in the overall control system lifecycle, but it does not eliminate the need for due diligence and following a process automation selection best practice. As with the initial acquisition of the legacy system, the target system will dictate the extent to which process automation can facilitate OpX and create a competitive advantage in your manufacturing operations for many years. CPAS selection in the context of migration warrants a unique perspective in each step of the process.

Migration Choices

At some point, users must choose to upgrade their existing control system or migrate to a new one. Sometimes, upgrades are not possible because the system has been phased out altogether or the installed system is based on an outdated architecture. ARC believes in migrating to a new system when the old one keeps users from taking advantage of a new business opportunity, or presents the imminent threat of unscheduled downtime.

Control system replacement is hard to justify. Usually, lower total cost of ownership (TCO) and better ease of use do not justify replacement. At best, you get a 25 percent cut in annual TCO, which is less than 2 percent of replacement cost. While the downtime threat of the existing system can be a major factor in the decision to migrate, the migration process itself can also cause interruption in process operations.

The market for process control systems has changed. Most PASs used to be sold for new installations in heavy process industries. Today, reduced capital spending, a depressed economy, and focus on getting more out of existing assets means that most systems sold are for replacement applications.

ARC believes that suppliers must address the issue of migrating their existing control system platforms to their new platforms first, and then address the issue of migration from competitor control systems. While it is true that many suppliers take advantage of competitive migration opportunities outside of their installed base, the issue of internal migration must be addressed first. Users are much more likely to stay with their installed supplier, unless the supplier gives them a reason to look elsewhere.

Larry O’Brien, [email protected], is research director, and Dave Woll, [email protected], is vice president, at ARC Advisory Group, Dedham, Mass.