Migration plan helps transition from legacy DCS platforms
Chemical company Arkema describes its migration to Rockwell Automation PlantPAx system. The program is said to give manufacturers a phased approach that eliminates many of the costs, risks, and complexities involved with migrating legacy DCSs, while providing...
A new three-step migration program from Rockwellrocesses, and lower maintenance and training costs.
“We’re responding to a market gap created by many vendors no longer supporting their systems,” says Mike Vernak, program manager, legacy DCS migration solutions program, Rockwell Automation. The program provides manufacturers with a phased approach that eliminates many of the costs, risks, and complexities involved with migrating legacy DCSs, while providing a single platform for integrating both process and discrete applications for improved productivity, lower costs and easier access to parts and service.”
Arkema decided to replace its 28-year-old DCS platform with the Rockwell Automation PlantPAx process automation system based on the Allen-Bradley ControlLogix programmable automation controller.
Phase one of the migration plan involves replacing legacy human-machine interface (HMI) consoles with Rockwell Software FactoryTalk View Site HMI infrastructure. In phase two, the legacy process controllers are replaced with Logix controllers, while allowing customers to reuse existing I/O modules to maximize the return on their existing investment. Phase three involves removing the legacy I/O infrastructure and replacing it with the Logix 1756-based I/O platform.
As part of the program, Vernak says Rockwell Automation has developed custom field termination unit cable designs that allow the removal of legacy I/O without the need to remove field wires, significantly reducing installation costs and risks associated with I/O replacement. The custom cables plug directly into the legacy field termination units on one end and into the 1756 I/O module on the other.
Arkema, a chemical company specializing in additives used to produce housing materials such as vinyl siding, was running half of its plant on a 28-year-old legacy DCS and the other half on a 15-year-old version of the same system. Not only were replacement parts a challenge to find, but obtaining talent to repair any breakdowns was nearly impossible. Adding to the situation, the company’s I/O hardware was almost 30 years old.
“Our existing DCS was unable to accommodate control changes, and finding resources for maintenance and repair was getting more difficult each day,” said John Bryant, Arkema engineering and maintenance manager. “But more importantly, safety concerns were starting to crop up.”
Arkema decided to replace its DCS platform with the Rockwell Automation PlantPAx process automation system based on the Allen-Bradley ControlLogix programmable automation controller (PAC). Communications interface applications in the PlantPAx software allow users to get required data from the factory floor and optimize communications with the controller. Working with Precision Engineering, a system integrator, and Rockwell Automation, Arkema created a migration plan that would provide the necessary diagnostics, as well as accommodate all the company’s priorities, such as the ability to interface with the current DCS, until the migration was complete.
The Rockwell Automation technical support team provided training for the line workers and engineers, helping them become acclimated to the new system and teaching them how to leverage the new automation features. Included with the technical support, Rockwell Automation led Arkema through its migration path. A Rockwell Automation Encompass Partner, Salem Automation, also played a key integration role with its ABNet software interface module. This device allows the new control system at Arkema to interface via EtherNet/IP with the remaining DCS.
The team finished phase one (replacing the control system, HMI and I/O) of the migration well within the six-month window necessary. The team expected to be at 100% production within three to four weeks of installation, but instead reached full optimum production during week one.
Read Control Engineering article, Upgrading Control: Migration of Evolution?
Renee Robbins , senior editor .
Control Engineering News Desk
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