Challenge
The era of the PLC5 has come to an end. The controller that once served companies well for many years is now obsolete, resulting in costly aftermarket replacement parts, limited capabilities, and downtime challenges. For one of the world’s largest mozzarella cheese producers, the key challenge with their legacy Allen Bradley PLC5 control system centered around its limited memory capacity and, consequently, the inability to handle new data collection and documentation requirements by U.S. Department of Agriculture (USDA). The cheese producer was further challenged to find a system integrator that had technical expertise with the obsolete architecture to leverage their existing automation investment and determine their migration options. Specialized in this matter, Automation Group was engaged to plan and manage the migration to the ControlLogix platform.
Solution
The customer’s Allen Bradley PLC5 control system used legacy communication protocols such as Remote I/O and DeviceNet. These networks were converted to ethernet communication with the use of aftermarket gateways and media converters. However, these short-term fixes to remain functional were not well-documented making the decision to reuse existing PLC5 I/O modules with “local” Remote I/O & DeviceNet gateways a difficult issue to troubleshoot while setting up their communication.
The Automation Group team implemented their success-proven phased approach for a timely migration. The team identified modern Rockwell processors with ample memory to support the new process documentation requirements in addition to the best location to physically install the new PLC in the customer’s existing control panels. Furthermore, Automation Group assigned a project team of engineers with strong PLC5 conversion experience to properly migrate to the new architecture and leverage the ControlLogix’s functionality.
Results
The preservation of archaic automation systems can be risky and expensive. With consideration to downtime costs and other performance challenges, the investment to migrate to a modern system may pay off sooner rather than later. “The migration provided our customer a solid basis to build for the future.” said Aaron Peri, Automation Group Project Manager. “It gives them the opportunity to take advantage of newer technologies as they continue to become available and enables them to meet the new, more stringent reporting requirements imposed by the USDA.”
Ultimately, Automation Group deployed a successful migration strategy that equipped the company to better meet regulatory demands. Although a migration process can seem daunting, it doesn’t have to be with the right system integrator partner.
