DEVICE AND METHOD FOR REAL-TIME MONITORING OF ACCIDENTAL DAMAGE TO THE PROTECTIVE COVERING OF UNDERGROUND OR IMMERSED METAL STRUCTURES OR PIPELINES

摘要

A method for monitoring damage to the protective covering ofimmersed or underground metal structures subjected tocathodic protection, based on the electrical resistanceoffered by the covering, and consisting of modulating thecathodic protection feed current and measuring thecorresponding potential variation due to the ohmic loss, theresistance being obtained from the ratio of potentialvariation to modulation current, to activate an alarm systemon sudden fall and rise in ohmic resistance due to accidentalevents.