Due to reliability concerns regarding the aging existing Distributed Control System (DCS), this major chemical manufacturer decided to replace it with a new system. This project involved the complete replacement of an obsolete ABB System 6 and Fischer Porter DCS, as well as Rockwell Automation PLCs and Triconex safety systems for the chemical supply chain. The replacement was completed in stages as part of a larger multi-generational program over a multi-year timeframe. Conversions were performed one process at a time and required the coordination of five process outages. In the largest process area, more than 800 I/O points were converted “live” to avoid an outage. In total, 1,800 I/O points were converted across two control rooms and five nestrooms.

SSOE’s instrumentation and controls professionals provided engineering services from Frontend loading (FEL) through detailed design to convert the legacy DCS system to a new Siemens PC57 system. Our FEL work included electrical and instrumentation and controls scope definition, including supporting disciplines. The detailed design scope included engineering for new and modified instrumentation, electrical UPS system, grounding, power to new control panels, heat tracing, motor control interfacing, electrical raceways, instrumentation and network cabling, junction boxes, Smart Plant Instrumentation (SPI) drawings for wiring from field instruments through junction boxes and to DCS cabinet terminations, instrument location plans, design reviews, construction work packages, construction support, and as-builts.

Detailed, accurate construction packages were delivered on time and within budget, with engineering driven field changes equaling less than 5% of the total installed cost.