Abstract: An arrangement for monitoring the potential of a cathodically protected buried metallic structure. The apparatus includes a measuring electrode to be inserted into the soil and electrically coupled to the metallic structure to be measured, a reference electrode placed on or in the soil, and a measuring circuit for measuring the potential difference between the measuring and reference electrodes. The measuring circuit also generates a reference potential to generate a pulse signal having a frequency proportional to the amount by which the measured potential exceeds the reference potential. A counter counts the number of pulses during a measuring cycle that is measured by a timer. A computer computes from timer and counter output data, the average value of the amount by which the measured potential exceeds the reference potential during a measuring cycle.