| Patent application number | Description | Published |
| 20090077793 | High Voltage Operating Rod Sensor and Method of Making the Same - 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. | 03-26-2009 |
| 20100072355 | ARC FLASH PROTECTION WITH SELF-TEST - 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. | 03-25-2010 |
| 20100254225 | FAULT TOLERANT TIME SYNCHRONIZATION - 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. | 10-07-2010 |
| 20110085272 | Systems and Methods for Generator Ground Fault Protection - 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. | 04-14-2011 |