Continuous CP monitoring for buried pipelines.

A cathodic-protection rectifier impresses a small DC current onto a buried pipeline to halt galvanic corrosion. The system works only as long as the impressed current, the rectifier output voltage, and the resulting pipe-to-soil potential stay inside narrow bands. When any of the three drifts out of range — a rectifier fault, a failing reference electrode, a coating breach — the pipeline starts corroding again, and on a 1,000 km pipeline a single bad rectifier can damage millions of euros of steel before anyone notices on a manual rounds inspection.

AutoLog® RTUs solve this by monitoring every CP rectifier continuously, alarming on drift, and reporting back to a central SCADA over GSM, TETRA or radio. The 16-bit analog inputs read CP voltage and current with the resolution the standard demands; the digital inputs supervise rectifier alarms; the on-board temperature sensors track cabinet conditions in the desert and the Arctic alike.

Beyond rectifier supervision, AutoLog deployments commonly include test-point pipe-to-soil potential measurement, intermittent reference-electrode reading, GPS time synchronisation for coordinated interrupter tests, and historical data logging for regulatory reporting.

We have shipped CP RTU networks across four continents. The product line was selected by some of the largest oil & gas producers in the world for exactly this application.