PROBLEM TO BE SOLVED: To provide a new electric protection system for a buried pipe in which AC signals causing noise in a damage monitoring system are not applied to a buried pipe.;SOLUTION: The electric protection system for the buried pipe comprises: an external power source; a conducting electrode for electric protection connected to the plus terminal of the external power source and installed in the earth; and a terminal for a buried pipe connected to the minus terminal of the external power source and connected to a buried pipe. Further, the external power source and the conducting electrode for electric protection, and the external power source and the terminal for a buried pipe are connected via AC signal shutdown filters capable of shutting down AC signals with prescribed frequencies.;COPYRIGHT: (C)2010,JPO&INPIT
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