Apparatus and method for detecting a fault in a distributed line network

An alarm arrangement for automatic alarm in response to detection of a specialized signal in a multi-phase distribution system monitoring a power-related waveform in a power line distributed from a non-residential loadcenter to each of a plurality of powered equipment, comprising:

• a specialized signal generator, activated in response to a fault being detected in the system, for producing a specialized signal that is unique with respect to the power-related waveform along one of the lines of the system;
• a control station for indicating that a specialized signal has been detected;
• and
• a plurality of line monitoring devices dispersed at respective locations adjacent the power line and between the loadcenter and respective ones of said power equipment and communicatively coupled to the control station, each of the line monitoring devices automatically alarming the control station in response to detection of the specialized signal at said respective location along at least one of the lines of the system, thereby identifying at the control station the location of the fault.

An arrangement for automatic selective circuit interruption in response to detection of a ground fault in a multi-phase, ungrounded or high-impedance grounded distribution system feeding power in a power line distributed via a power-related waveform from a non-residential loadcenter to each of a plurality of powered equipment through a plurality of network branches, comprising:

• a specialized signal generator, activated in response to a fault being detected in the system, for producing a specialized signal that is unique with respect to the power-related waveform along one of the lines of the system;
• a plurality of circuit interrupters located throughout the networked system, each of the circuit interrupters actuated to prevent the flow of current in lines of the system positioned downstream from the actuated circuit interrupter;
• and
• a plurality of line monitoring devices, each communicatively coupled to a circuit interrupter co-located with the line monitoring device, such that each line monitoring device automatically actuates the coupled circuit interrupter in response to detection of the specialized signal so as to isolate a section of the networked system having the ground fault.

A method of automatically interrupting a circuit in response to detection of a ground fault in a multi-phase, ungrounded or high-impedance grounded distribution system monitoring power in a power line distributed via a power-related waveform from a non-residential loadcenter to each of a plurality of powered equipment, which comprises the steps of:

• detecting a ground fault in the system;
• in response to the step of detecting a fault, producing a specialized signal that is unique with respect to the power-related waveform along one of the lines of the multi-phase system;
• detecting the specialized signal in the faulted phase of the system;
• and
• in response to the step of detecting the specialized signal, automatically interrupting the flow of current in a section of the system having the fault so as to isolate the section the system having the fault.

An alarm arrangement for automatic alarm in response to detection of a specialized signal in a multi-phase distribution system monitoring a power-related waveform in a power line distributed from a non-residential loadcenter to each of a plurality of powered equipment, comprising:

• a specialized signal generator, activated by the control station in response to a fault being detected in the system, for producing a specialized signal that is unique with respect to the power-related waveform along one of the lines of the system;
• a control station for indicating that a specialized signal has been detected;
• and
• a plurality of line monitoring devices dispersed at respective locations adjacent the power line and between the loadcenter and respective ones of said power equipment and communicatively coupled to the control station, each of the line monitoring devices automatically alarming the control station in response to detection of the specialized signal at said respective location along at least one of the lines of the system, thereby identifying at the control station the location of the fault;
• at least one circuit interrupter constructed and arranged to interrupt the power in a segment of the power line in response to one of the plurality of line monitoring devices automatically alarming the control station.

An arrangement for automatic selective circuit interruption in response to detection of a ground fault in a multi-phase, ungrounded or high-impedance grounded distribution system feeding power in a power line distributed via a power-related waveform from a non-residential loadcenter to each of a plurality of powered equipment through a plurality of network branches, comprising:

• a specialized signal generator, activated in response to a fault being detected in the system, for producing a specialized signal that is unique with respect to the power-related waveform along one of the lines of the system;
• a plurality of circuit interrupters located throughout the networked system, each of the circuit interrupters actuated to prevent the flow of current in lines of the system positioned downstream from the actuated circuit interrupter;
• a control station which activates the specialized signal generator in response to being alarmed that a fault has been detected in the system;
• and
• a plurality of line monitoring devices, each communicatively coupled to a circuit interrupter co-located with the line monitoring device, such that each line monitoring device automatically actuates the coupled circuit interrupter in response to detection of the specialized signal so as to isolate a section of the networked system having the ground fault.