Cable continuity monitoring system

Abstract

There is disclosed a monitoring system for insuring the continuity and integrity of a power distribution system comprising a plurality of trailing cables, each trailing cable connected at a central station to a common power source and transmitting a power energizing signal to a load disposed at a remote location. In particular, the monitoring system comprises a transmitter and receiver for each trailing cable of the power distribution system whereby a monitoring signal is transmitted from the central station to the remote location and returned to be detected by the receiver. If there is a fault condition within the trailing cable, the receiver provides a signal indicative thereof to be applied to a circuit breaker or coupling switch actuating the coupling switch to its open position thereby disconnecting the power from the trailing cable and its load. When a monitoring signal is successively transmitted and detected, the receiver provides a manifestation indicating the integrity and continuity of its trailing cable and actuates its coupling switch to its closed position, thus applying an energizing signal via its conductor to the load. The transmitter dedicated to each trailing cable includes means responsive to the frequency or frequencies of the previously generated monitoring signals, even from other transmitters, for generating a monitoring signal of substantially the same frequency whereby the monitoring signals as applied via the common AC power bus will be of substantially the same frequency. As a result, the monitoring system of this invention tends to eliminate the production of difference or beat signals and the resultant false indications of a fault condition within one or more of the trailing cables.