Description
DCVG (Direct Current Voltage Gradient) is a survey technique used for locating and sizing of pipeline coating defects. Basically, this method measures voltage gradients on pipelines with impressed DC current. It relies on a pulsed ON reading to determine current direction. Accuracy of location and severity are very precise. This method uses either an analog or digital meter coupled with sub meter GPS to provide improved accuracy and reliability. As with ACVG, the accuracy depends on the soil conditions. Coupled with close interval survey, this method is highly effective for ECDA.