FIELD: pipe-line transport, specifically, remote location of leaks in pipe-lines and cathode protection of pipe-lines in most important sections. SUBSTANCE: cathode protection and pipe-line diagnostics system has external metal electrode employed as anode placed on external surface of insulation layer of pipe-line, D C power supply source, additional grid electrode positioned in insulation layer. Besides them system is fitted with control unit incorporating two synchronous A C voltage sources with controllable constant component connected on two sides via meters to outputs of additional grid electrode and pipe, eight meters testing current and voltage and phase shift in A C circuits, personal computer to which outputs of all meters are connected. System is applicable for oil, gas and other product pipe-lines for protection and diagnostics of external surfaces of pipes, allows running test of condition of insulation to be conducted and time and extent of repair operations to be planned on its basis. EFFECT: enhanced accuracy of diagnostics. 5 dwg
