Automating Reverse Engineering to Achieve a 90 Percent Savings on Engineering Hours

OC San began upgrading its SCADA system and PLC architecture to provide more granular equipment graphics that show permissive conditions, rather than a single status indicator. Operators needed a faster way to identify which specific permissive conditions prevented equipment, such as pumps, from running without inspecting each PLC program manually. The upgrade required extracting upward of 46,000 permissive states from more than 40 ProWORX NxT PLC programs, a task that would have required an estimated minimum of 1,150 person-hours if performed manually.

Tetra Tech deployed InSpect framework, our proprietary algorithmic toolset, to automate reverse engineering of PLC logic and extract permissive conditions at scale. We then applied InSpect across OC San’s ProWORX NxT programs to populate device-level permissive states for SCADA graphics. The tool was tested for accuracy and verified to analyze conditions at an average speed of 0.04 milliseconds per condition, many magnitudes faster than the roughly 90 seconds per condition required for manual inspection. Automation reduced analysis time per condition from 90,000 milliseconds to 0.04 milliseconds and achieved approximately 90 percent savings on engineering hours compared with manual review. The faster, validated outputs enabled timely SCADA graphics updates and more effective operator troubleshooting.