CIRCUIT MONITOR AND CONTROL EQUIPMENT

摘要

PURPOSE:To secure a monitor and control function even if a fault is generated in a circuit for using a monitor and control circuit in common with a main circuit by generating a substitute frame synchronizing signal and a substitute parity signal from an adjacent repeating installation of a faulty point of a circuit, superposing a monitor signal on said signal and transmitting it. CONSTITUTION:A circuit LA and LB are disconnected at a point X, a main signal is not received by a receiving part 21 of an up-circuit repeater 13a, therefore, an input disconnection signal from an integrator 35 becomes below a prescribed level. By this signal, a switch part 24 sends a substitute signal from a substitute signal generating part 23, to an inserting part 25. In the inserting part 25, a monitor signal of a down-circuit is also inserted in advance, and in this part, the monitor signal is superposed on the substituting signal and sent to the next repeating installation. Accordingly, in a circuit monitor equipment of a terminal station B, a monitor signal of the repeating installation related to the circuit LB extending from the terminal station B to the point X is obtained. Said substitute signal consists of a substitute frame synchronizing signal of the same period as the main signal, and a substitute parity signal opposite to the parity side. Accordingly, the terminal station B can discriminate immediately a disconnection of the circuit. The above-mentioned fact is the same with regard to a repeater in the down-direction of the faulty point, as well.