Abstract: An method for automatically testing an arc flash detection system by periodically or continually transmitting electro-optical (EO) radiation through one or more transmission cables electro-optically coupled to respective EO radiation collectors. A test EO signal may pass through the EO radiation collector to be received by an EO sensor. An attenuation of the EO signal may be determined by comparing the intensity of the transmitted EO signal to an intensity of the received EO signal. A self-test failure may be detected if the attenuation exceeds a threshold. EO signals may be transmitted according to a particular pattern (e.g., a coded signal) to allow an arc flash detection system to distinguish the test EO radiation from EO radiation indicative of an arc flash event.

Abstract: An method for automatically testing an arc flash detection system by periodically or continually transmitting electro-optical (EO) radiation through one or more transmission cables electro-optically coupled to respective EO radiation collectors. A test EO signal may pass through the EO radiation collector to be received by an EO sensor. An attenuation of the EO signal may be determined by comparing the intensity of the transmitted EO signal to an intensity of the received EO signal. A self-test failure may be detected if the attenuation exceeds a threshold. EO signals may be transmitted according to a particular pattern (e.g., a coded signal) to allow an arc flash detection system to distinguish the test EO radiation from EO radiation indicative of an arc flash event.

Abstract: A generator winding-to-ground fault detection system is disclosed that includes a signal injection source in electrical communication with a winding of an electric power generator via an injection transformer. The winding may be coupled to ground via a winding-to-ground path and the signal generation source may generate an injection signal capable of being injected to the winding using the injection transformer. The disclosed system may further include a protection module in communication with the signal injection source and the electric power generator configured to receive the injection signal and a signal relating to the current through the winding-to-ground path, and to determine the occurrence of a winding-to-ground fault condition based at least in part on the injection signal and the signal relating to the current through the winding-to-ground path.

Abstract: Methods for making and using vacuum switching devices are disclosed. A vacuum switching device has an operating rod for actuating a movable electrical contact within the device. The operating rod may be a hollow epoxy glass tube with an electrical sensor disposed within it, and there may be an elastomeric polymer filling compound disposed within the tube and encasing the sensor. The operating rod may be attached to the movable electrical contact on one end by a steel end-fitting that has been press-fit into the tube and secured with at least one cross pin. In this way, a very secure electromechanical connection may be made between the operating rod and the rest of the vacuum switching device, and the sensor is protected from shock associated with the operation of the device. Moreover, the vacuum switching device is compact and easy to construct.

Abstract: Systems and methods for distributing accurate time information to geographically separated communications devices are disclosed. Additionally, the desired systems and methods may adjust local time signals to compensate for measured signal drifts relative to more accurate time signals. Moreover, a system may determine a best available time signal based on a weighted average of available time signals or select a best available time signal based on weighted characteristics of various time signals. A system may be further configured to transmit time information embedded in an overhead portion of a SONET frame, including transmission of a standard or common time.

Abstract: An method for automatically testing an arc flash detection system by periodically or continually transmitting electro-optical (EO) radiation through one or more transmission cables electro-optically coupled to respective EO radiation collectors. A test EO signal may pass through the EO radiation collector to be received by an EO sensor. An attenuation of the EO signal may be determined by comparing the intensity of the transmitted EO signal to an intensity of the received EO signal. A self-test failure may be detected if the attenuation exceeds a threshold. EO signals may be transmitted according to a particular pattern (e.g., a coded signal) to allow an arc flash detection system to distinguish the test EO radiation from EO radiation indicative of an arc flash event.

Abstract: A current measurement device using a Rogowski coil having a generally toroidally shaped core with flattened faces, a first winding in one direction, a second winding forming a return loop, and a temperature compensation and scaling network coupled to the coil. The core has concentric cavities and a rough surface to restrain movement of the coil winding. A Faraday shield is wrapped over the coil. One shield is “serpentine,” having staggered (offset) lateral extensions from a central region. An alternate shield has a generally circular central region with extensions in generally radial directions. The shield is formed of three layers comprising a non-ferromagnetic metal central layer surrounded by insulative layers. At an end tab of the shield, the metal layer is exposed for connection to a ground lug or other connector. An insulative housing envelops the coil and electrical network. An output wire terminates in an industrial connector. A resistive network may be implemented with the current measurement device.

Abstract: Methods and system for making and using vacuum switching devices are disclosed. A vacuum switching device has an operating rod for actuating a movable electrical contact within the device. The operating rod may be a hollow epoxy glass tube with an electrical sensor disposed within it, and there may be an elastomeric polymer filling compound disposed within the tube and encasing the sensor. The operating rod may be attached to the movable electrical contact on one end by a steel end-fitting that has been press-fit into the tube and secured with at least one cross pin. In this way, a very secure electromechanical connection may be made between the operating rod and the rest of the vacuum switching device, and the sensor is protected from shock associated with the operation of the device. Moreover, the vacuum switching device is compact and easy to construct.

Abstract: A system for remotely controlling and monitoring an electrical system includes an electrical system controlling device connected to the electrical system for monitoring and controlling the electrical system and electronic controls for monitoring and controlling the electrical system controlling device. A wireless communications interface enables remote wireless access to the electronic controls.

Abstract: An improved Rogowski coil is formed on a toroidal core made of a thermoplastic or other moldable material, the core having a preferably continuous groove or grooves extending around the core. The grooves correspond in size to magnet wire which registers within the grooves, thus controlling the specific location of the wires. The grooving may be helical. A return loop can be provided for return path cancellation, or a reverse winding can be added in a direction opposite to the direction of advancement of the main coil. In using the return loop, a resistive network can be added to improve the cancellation of the return path due to the effect of geometries. In addition, it can compensate for thermal and other variations.

Abstract: Methods and system for making and using vacuum switching devices are disclosed. A vacuum switching device has an operating rod for actuating a movable electrical contact within the device. The operating rod may be a hollow epoxy glass tube with an electrical sensor disposed within it, and there may be an elastomeric polymer filling compound disposed within the tube and encasing the sensor. The operating rod may be attached to the movable electrical contact on one end by a steel end-fitting that has been press-fit into the tube and secured with at least one cross pin. In this way, a very secure electromechanical connection may be made between the operating rod and the rest of the vacuum switching device, and the sensor is protected from shock associated with the operation of the device. Moreover, the vacuum switching device is compact and easy to construct.

Abstract: At least one of input channel containing information relative to a power system or a subpart of a power system is analyzed by a computation engine along with a test data channel. The results of the computation performed on the test data channel are compared against a predetermined test result, and if the two differ, a corrective action is taken.

Abstract: Methods and systems for spatially assisted fault reporting in a distribution system. Typical steps of the methods may include determining the location of the fault or the distance to the fault, generating and storing a plurality of waypoints representative of the route of the distribution system, processing the plurality of waypoints, determining spatial coordinates of the fault, generating a fault report, and communicating the fault report.

Abstract: A line disturbance detector is disclosed which oversees the operation of power protection devices monitoring the same conductor, and only allows a power automation or control operation when both the disturbance detector and a traditional power protection device, such as a protection relay, determine such an operation is required.

Abstract: A current measurement device using a Rogowski coil having a generally toroidal-shaped core with a first winding in one direction and a second winding forming a return loop. The coil is positioned within a two-piece electrostatic shield. A first piece of the electrostatic shield is a partially donut-shaped member having a U-shaped cross-section. The coil is positioned in the donut-shaped member and covered by an encapsulating material. The first piece includes a slit through the cross-section thereof to prevent an electrical loop around the perimeter thereof. The second piece of the electrostatic shield is flat and has a donut-shaped configuration. The second piece is configured with inside and outside peripheral edges such that only one or none of the inside/outside edges contact the first piece. The second piece also has a cross-sectional slit which is in registry with the slit in the first piece.

Abstract: A current measurement device using a Rogowski coil having a generally toroidally shaped core with flattened faces, a first winding in one direction, a second winding forming a return loop, and a temperature compensation and scaling network coupled to the coil. The core has concentric cavities and a rough surface to restrain movement of the coil winding A Faraday shield is wrapped over the coil. One shield is “serpentine,” having staggered (offset) lateral extensions from a central region An alternate shield has a generally circular central region with extensions in generally radial directions. The shield is formed of three layers comprising a non-ferromagnetic metal central layer surrounded by insulative layers. At an end tab of the shield, the metal layer is exposed for collection to a ground lug or other connector. An insulative housing envelops the coil and electrical network An output wire terminates in an industrial connector A resistive network may be implemented with the current measurement device.

Abstract: An improved Rogowski coil is formed on a toroidal core made of a thermoplastic or other moldable material, the core having a preferably continuous groove or grooves extending around the core. The grooves correspond in size to magnet wire which registers within the grooves, thus controlling the specific location of the wires. The grooving may be helical. A return loop can be provided for return path cancellation, or a reverse winding can be added in a direction opposite to the direction of advancement of the main coil. In using the return loop, a resistive network can be added to improve the cancellation of the return path due to the effect of geometries. In addition, it can compensate for thermal and other variations.

Abstract: A precision printed circuit board based Rogowski coil is formed including a printed circuit board including a first layer and second layer. The printed circuit board further defines an aperture for receiving an electrical path therethough. A first return path is defined about the aperture on the first layer of the printed circuit board, and a second return path—parallel to the first return path—is defined about the aperture on the second layer of the printed circuit board. A plurality of radial paths defined on the first layer of printed circuit board extend between the aperture and the first return path. A plurality of radial paths defined on the second layer of the printed circuit board extend between the aperture and the second return path. Each first layer radial path is connected with an adjacent second layer radial path to form a generally toroidally-shaped winding.

Abstract: An improved Rogowski coil is formed on a toroidal core made of a thermoplastic or other moldable material, the core having a preferably continuous groove or grooves extending around the core. The grooves correspond in size to magnet wire which registers within the grooves, thus controlling the specific location of the wires. The grooving may be helical. A return loop can be provided for return path cancellation, or a reverse winding can be added in a direction opposite to the direction of advancement of the main coil. In using the return loop, a resistive network can be added to improve the cancellation of the return path due to the effect of geometries. In addition, it can compensate for thermal and other variations.

Abstract: In one general aspect, a system to control and monitor an electrical system includes a switchgear housing unit connected to the electrical system that includes a switchgear mechanism for controlling a connection within the electrical system and electronic controls for monitoring and controlling the switchgear mechanism, where the electronic controls are embedded within the switchgear housing unit to form a single, self-contained unit.