If there’s one thing the focus on the Industrial Internet of Things and the digital transformation of industry has done, it’s getting nearly every company to more critically assess the capabilities of their automation systems. Whereas, in the past, this kind of assessment was largely done to ensure maximum production equipment uptime, connectivity and security issues are equally important considerations today.
Despite the growing numbers of processing companies realizing the need to upgrade legacy distributed control systems (DCS) to position their operations for the future, many users are cautious about moving forward—daunted by the operational disruption required to bring a new system online.
While upgrading a control system is no easy task—no matter how it’s done—the good news is that the rip-and-replace process once common to this undertaking is no longer a requirement.
“Addressing the vulnerabilities that are present with a legacy DCS does not always require a disruptive all-at-once approach,” says Dwight Wood, vice president of global sales for NovaTech, whose D/3 DCS system was introduced 38 years ago. “For a plant of any scale running at or near capacity, taking down processing lines for any amount of time can be extremely expensive in terms of lost production and business impact.”
This multi-stage upgrade typically begins with a deep dive into the current system and application. “We begin the process diagnostically to identify the pain points, gaps, operating challenges, and any other potential risks in the current process and control system implementation," says Wood. "Approaching the process this way supports a more targeted approach that focuses on areas of improvement that can bring the greatest impact in terms of operations and addressing risk exposure.”
A multi-stage migration approach can often begin by integrating new DCS components with new and existing I/O devices, adds Oakey. “Since I/O is one of the most significant investments in an automation upgrade, I/O drops can be replaced in a phased manner over time allowing for spare parts capture from decommissioned drops, phased implementation aligned with plant outage limitations, and staggered financial investment,” he explains.
This approach to DCS upgrades also enables users to go beyond direct automation system component upgrades and address integration with enterprise systems as well. “Customers want more than an effective implementation of the Level 2 automation system,” Wood says. “They often want improved data capture and the conversion of that data into useful knowledge presented in desktop KPI [key performance indicator] dashboards that can be utilized at the manufacturing execution system (MES) level and/or the enterprise resources planning (ERP) level.”
Oakey adds that the total lifecycle cost of ownership needs to be factored into any DCS or control system migration or replacement project. “The financial investment in replacing a control system encompasses more than the initial outlay for new hardware, software and engineering services,” he says. “Process manufacturers need to also consider recurring maintenance, service support, and upgrade costs that they will incur over what can easily be a 20-year or more lifespan. We work with our customers upfront to define this cost and provide a system life cycle plan to effectively manage and support the overall investment.”
“A DCS sits on top of an inherently dynamic processing environment made more so as new equipment is added, production lines are expanded, and as issues like obsolescence and cybersecurity present new challenges over time,” explains Wood. “That is easier to navigate if there is a well-defined system life cycle plan and migration path forward that includes a carefully thought-out execution plan for success.”
