Locating underground electrical contacts and open couplings on coated pipelines is one of the major field problems in the installation and maintenance of a cathodic protection system. Locating and removing these contacts or open couplings is often very time consuming and expensive, particularly in urban areas where a considerable amount of the system lies under paving and in close proximity with other underground structures. Another hindrance is alternating current interference from overheat power lines or where the ac ground neutrals are connected to the system.
展开▼
