Abstract: In accordance with at least one aspect of this disclosure, a system can include a primary coil wound around a moveable magnetic core, at least one secondary coil wound in one continuous direction and magnetically coupled with the primary coil, and a controller operatively connected to determine a position of the moveable magnetic core and configured to detect a fault across the secondary coil.

Abstract: A proximity sensor system can include a target assembly having one or more first targets comprising a first material having first magnetic permeability and one or more second targets comprising a second material having a second magnetic permeability. The system can include 5 an inductive proximity sensor positioned relative to the target assembly to sense an inductance of the target assembly. The inductive proximity sensor and/or the target assembly are configured to move relative to the other.

Abstract: In accordance with at least one aspect of this disclosure, a system can include a primary coil wound around a moveable magnetic core, at least one secondary coil wound in one continuous direction and magnetically coupled with the primary coil, and a controller operatively connected to determine a position of the moveable magnetic core and configured to detect a fault across the secondary coil.

Abstract: Provided are embodiments for circuit for detecting an open-wire condition for a differential input. Embodiments include a sensor, and a line replaceable unit (LRU) coupled to the sensor, wherein the LRU comprises a differential amplifier to provide a sensor output. Embodiments can also include a synchronous demodulator coupled to an output of the differential amplifier through an alternating current (AC) coupling network, wherein the synchronous demodulator is configured to receive the differential amplifier output and a reference signal at the synchronous demodulator signal input and reference input, and provide a synchronous demodulator output voltage to indicate an open-wire condition. Also provided are embodiments of a method for detecting an open-wire condition for a differential input.

Abstract: A shaft monitoring system includes a rotatable shaft having a target element coupled thereto that rotates along with the shaft. A proximity sensor is located adjacent to the target element. The proximity sensor measures an inductance of the target element based on one or both of a volume of the target element and a distance between the target element and the proximity sensor, and generates a proximity sensor output signal based on the measured inductance. A signal processing system determines at least one of a position of the shaft, a rotational speed of the shaft, and a rotational direction of the shaft based on the proximity sensor output signal.

Abstract: Provided are embodiments for circuit for detecting an open-wire condition for a differential input. Embodiments include a sensor, and a line replaceable unit (LRU) coupled to the sensor, wherein the LRU comprises a differential amplifier to provide a sensor output. Embodiments can also include a synchronous demodulator coupled to an output of the differential amplifier through an alternating current (AC) coupling network, wherein the synchronous demodulator is configured to receive the differential amplifier output and a reference signal at the synchronous demodulator signal input and reference input, and provide a synchronous demodulator output voltage to indicate an open-wire condition. Also provided are embodiments of a method for detecting an open-wire condition for a differential input.

Abstract: A voltage differential testing circuit can include a first positive line configured to connect to a positive voltage source, and a first negative line configured to connect to a negative voltage source. The circuit can include a plurality of components arranged and configured to output an output voltage when a voltage differential between a positive voltage line and a negative voltage line is within a voltage range.

Abstract: A shaft monitoring system includes a rotatable shaft having a target element coupled thereto that rotates along with the shaft. A proximity sensor is located adjacent to the target element. The proximity sensor measures an inductance of the target element based on one or both of a volume of the target element and a distance between the target element and the proximity sensor, and generates a proximity sensor output signal based on the measured inductance. A signal processing system determines at least one of a position of the shaft, a rotational speed of the shaft, and a rotational direction of the shaft based on the proximity sensor output signal.

Abstract: Apparatus and associated methods relate to detection of an overcurrent condition by determining if a voltage across a current-sense resistor exceeds a predetermined voltage threshold. The voltage at each side of the current-sense resistor is sensed indirectly, through a diode network. The diode networks through which the voltages on each side of the current-sense resistor are biased differently from one another. Such differently-biased diode networks translate the voltages at each side of the current-sense resistor by different amounts, the biasing of these diode networks is such that a voltage difference between the second terminals of the first and second diode networks is of a first polarity during normal current conditions, and the voltage difference between the second terminals of the first and second diode networks is of a second polarity during overcurrent conditions.

Abstract: A system for compensating for photodiode errors includes a live photodiode configured to be exposed to a light source and to output a live signal. The system further includes a reference photodiode located proximate to the live photodiode and configured to be isolated from the light source and to output a reference signal. The system further includes a controller configured to generate a compensated output signal by subtracting the reference signal from the live signal.

Abstract: Apparatus and associated methods relate to detection of an overcurrent condition by determining if a voltage across a current-sense resistor exceeds a predetermined voltage threshold. The voltage at each side of the current-sense resistor is sensed indirectly, through a diode network. The diode networks through which the voltages on each side of the current-sense resistor are biased differently from one another. Such differently-biased diode networks translate the voltages at each side of the current-sense resistor by different amounts, the biasing of these diode networks is such that a voltage difference between the second terminals of the first and second diode networks is of a first polarity during normal current conditions, and the voltage difference between the second terminals of the first and second diode networks is of a second polarity during overcurrent conditions.

Abstract: A voltage differential testing circuit can include a first positive line configured to connect to a positive voltage source, and a first negative line configured to connect to a negative voltage source. The circuit can include a plurality of components arranged and configured to output an output voltage when a voltage differential between a positive voltage line and a negative voltage line is within a voltage range.

Abstract: Provided are embodiments for a circuit including a resolver having a primary winding and a set of secondary windings, wherein the resolver has a resolver shaft, and a polarity detection circuit coupled to the resolver. The circuit can also include a synchronizer circuit coupled to the polarity detection circuit, wherein the synchronizer circuit synchronizes signals from the positive polarity detection circuit; and a controller configured to determine a direction of the resolver shaft using the output of the synchronizer circuit. Also provided are embodiments of a method for determining the resolver rotation direction using non-analog means.

Abstract: Provided are embodiments for a circuit including a resolver having a primary winding and a set of secondary windings, wherein the resolver has a resolver shaft, and a polarity detection circuit coupled to the resolver. The circuit can also include a synchronizer circuit coupled to the polarity detection circuit, wherein the synchronizer circuit synchronizes signals from the positive polarity detection circuit; and a controller configured to determine a direction of the resolver shaft using an output of the synchronizer circuit. Also provided are embodiments of a method for determining the resolver rotation direction using non-analog means.

Abstract: Embodiments herein relate to a sensor fault measurement system. The system includes a sensor having a primary winding, a first secondary winding and a second secondary winding and a wiring harness operably connected to the primary winding, first secondary winding and second secondary winding of the sensor. The system also includes a controller operably connected to the wiring harness. The controller includes a bias network configured to apply a common mode DC voltage bias of opposite sign to the first sensor output and the second sensor output respectively, and a fault sense circuit configured to monitor the DC voltage bias on first sensor output and the DC voltage bias on second sensor output, and identify a sensor fault if at least one of the DC voltage bias on first sensor output and the DC voltage bias second sensor output is impacted beyond a selected threshold.

Abstract: Embodiments herein relate to a sensor fault measurement system. The system includes a sensor having a primary winding, a first secondary winding and a second secondary winding and a wiring harness operably connected to the primary winding, first secondary winding and second secondary winding of the sensor. The system also includes a controller operably connected to the wiring harness. The controller includes a bias network configured to apply a common mode DC voltage bias of opposite sign to the first sensor output and the second sensor output respectively, and a fault sense circuit configured to monitor the DC voltage bias on first sensor output and the DC voltage bias on second sensor output, and identify a sensor fault if at least one of the DC voltage bias on first sensor output and the DC voltage bias second sensor output is impacted beyond a selected threshold.