Abstract: A system for communicating measurement data from each fuel cell or a group of fuel cells in a fuel cell stack, including a plurality of fuel cells and a plurality of stack plates, where one stack plate is between each fuel cell and on each end of the stack. The system includes a plurality of embedded smart plates where each embedded smart plate is mechanically and electrically coupled to at least one of the plurality of stack plates, and where each embedded smart plate includes optical transceivers on a top side and a bottom side of the smart plate. The system further includes at least one aggregator device having at least one optical transceiver to initiate a series of communications between the embedded smart plates to determine the location and data collected by each of the smart plates.

Abstract: A system for communicating measurement data from each fuel cell or a group of fuel cells in a fuel cell stack, including a plurality of fuel cells, a plurality of stack plates, and a plurality of embedded smart plates. The stack plates are between each fuel cell and on each end of the stack, and the plurality of embedded smart plates are mechanically and electrically coupled to at least one of the plurality of stack plates, and each smart plate including optical transceivers on the top side and the bottom side. The system further includes first and second aggregator devices, said first and second aggregator devices including at least one optical transceiver for communicating with the embedded smart plate adjacent to the first or second aggregator device, where one aggregator device initiates communication with the embedded smart plates and the other aggregator device completes communication.

Abstract: A measurement circuit that has particular application for detecting a high impedance measurement signal from a liquid water sensor. The measurement circuit includes a high impedance resistance-to-frequency conversion circuit that is coupled to the sensor and receives a resistance signal therefrom. The resistance-to-frequency conversion circuit includes an oscillator that converts the resistance signal to a representative frequency. The measurement circuit also includes a frequency-to-voltage conversion circuit that receives the frequency signal from the resistance-to-frequency conversion circuit, and converts the frequency signal to a representative voltage that provides an indication of water on the sensor.

Abstract: A high-precision Rogowski current transformer, the Rogowski coil is realized in a single printed circuit board while maintaining both the outside field rejection of a traditional Rogowski coil, and the increased output voltage similar to the multiple printed circuit board Rogowski coil arrangements.

Abstract: A method and apparatus for a high frequency resistance measurement instrument with a reasonable dynamic range, which militates against saturation in the presence of one or more large undesirable signals, the high frequency measurement instrument capable of employing multiple alternating currents of differing frequencies to maintain measurement capability despite signal chain saturation in the presence of a large undesirable signal.

Abstract: A method and apparatus for a high frequency resistance measurement instrument with a reasonable dynamic range, which militates against saturation in the presence of one or more large undesirable signals, the high frequency measurement instrument capable of employing multiple alternating currents of differing frequencies to maintain measurement capability despite signal chain saturation in the presence of a large undesirable signal.

Abstract: A high-precision Rogowski current transformer, the Rogowski coil is realized in a single printed circuit board while maintaining both the outside field rejection of a traditional Rogowski coil, and the increased output voltage similar to the multiple printed circuit board Rogowski coil arrangements.