Energy Company’s DCS Overhaul Nearly Halves Shutdowns

As Rockwell Automation makes a bigger push into the energy space, it’s showing off its success with one energy company in northern and central California. Ripon Cogeneration has reduced startup time by 30 percent with Rockwell’s PlantPAx process automation system, and has reduced the number of nuisance trips by almost 90 percent.

Ripon’s previous distributed control system (DCS) faces issues with availability, serviceability, proprietary networks and downtime. Multiple fail-safes were hard-coded into the previous DCS, so even small deviations in process variables would trip the entire system and force the 50 MW plant to shut down. Operators and technicians at the 25-year-old gas-fired plant could only react to the safety trips, which occurred as often as three times each day.

Ripon also faced issues with its control system software—a proprietary operating system with little or no vendor support. “Besides significantly reducing costly shutdowns, the PlantPAx system has helped us comply better with state emissions and other regulations,” said Brett Weber, operations and maintenance manager for Ripon. “That’s because the controls are automated, and operators can easily monitor variables through the PlantPAx dashboards in real time.”

The PlantPAx system supplied to Ripon includes an information-enabled, scalable, multidiscipline control platform that combines process and safety control with communication and state-of-the-art I/O. The system is equipped with 750 I/O points and can collect up to 1,000 points of process data. The plant’s old proprietary network was replaced with EtherNet/IP, allowing easy installation of the new system and smooth integration with the existing plant subsystems.

Ripon’s cogeneration plant also moved from a manual data-collection process that was prone to errors to PlantPAx’s data historian software, plus a visualization, analysis and reporting portal that provides instant insight into production. The PlantPAx system leverages all historical data from the process system and automates daily production reports.

“By implementing a modern DCS, Ripon Cogeneration now has the flexibility to respond to external pressures, such as regulatory compliance, while increasing efficiencies and productivity across its operation,” said Steve Pulsifer, director of process market development for Rockwell Automation.