A sensor includes: a hole; a sensing area formed around the hole, wherein at least one sensor is in the sensing area; and a crack detector configured to output a first crack signal if a comparison value obtained by comparing a detected value from the at least one sensor with a reference value exceeds an error range.

A system and method for detecting a failure in a redundant signal path during operation of the redundant path is disclosed. A test signal is sequentially injected into each signal path while an input signal is conducted by the other signal path not receiving the test signal. The test signal is selected at a frequency to verify operation of a filter connected in series along each path. A processor generates the test signal, injects the test signal at the input of the filter, and receives the output of the filter. The processor then generates a frequency response of the filter in each signal path as a function of the output from the filter and of the original test signal. The frequency response obtained along each of the redundant signal paths is compared to each other to detect a failure of one of the filters present along the respective signal paths.

An apparatus is disclosed for making circuitry with passive fundamental components more robust. In example implementations, an apparatus includes at least one passive fundamental component and at least one redundant passive fundamental component. The apparatus also includes fault tolerant circuitry coupled to the at least one passive fundamental component and the at least one redundant passive fundamental component. The fault tolerant circuitry includes fault detection circuitry configured to detect a fault of the at least one passive fundamental component. The fault tolerant circuitry also includes component repair circuitry configured to disconnect the at least one passive fundamental component based on the fault.

Systems and methods for monitoring current anomaly are described. In an example, a device can measure first current flowing along a first liner between an instrument to an equipment. The device can measure second current flowing along a second line between the equipment to the instrument. The device can compare the measurements of the first current and the second current. The device can identify a presence of current anomaly based on the comparison of the measurements of the first and second currents. The device can, in response to the presence of the current anomaly, disconnect the instrument from the equipment.

A high-frequency 5 measurement method includes generating a test signal (TS), which is a sine-wave signal having a predetermined frequency, in which a period (τ) during which the power level is at a first power level and a period (T-τ) during which the power level is at a second power level lower than the first power level 10 are periodically repeated, inputting the test signal (TS) to a device under test (10) as an input signal, and measuring the difference between an output signal (OUT) of the device under test (10) and an ideal value of the output signal (OUT).

A measurement device measures a frequency response of a servo system, applies predetermined oscillation are associated with each other to the servo system, identifies, from a result of oscillation application, a pair of a first oscillation application signal and a first response signal, and identifies a pair of a second oscillation application signal and a second response signal. Then, a first frequency response that is a frequency response is calculated on the basis of the first oscillation application signal and the first response signal, a second frequency response that is a frequency response is calculated on the basis of the second oscillation application signal and the second response signal, and the first frequency response and the second frequency response are synthesized.

A testing system for monitoring a machine under test is disclosed and includes one or more high frequency sensors configured to generate a sensor signal that is representative of an operating parameter of the machine. The high frequency sensors have a required high frequency sampling rate. The testing system also includes a notification device configured to generate a notification indicating the operating parameter monitored by the high frequency sensors has exceeded a predefined threshold value and a data acquisition control module configured to monitor the high frequency sensors at a first sampling rate. The testing system also includes a monitoring control module in electronic communication with the notification device. The monitoring control module is configured to monitor the high frequency sensors at a second sampling rate that is greater than the first sampling rate and at least equal to the required high frequency sampling rate.

The present disclosure a program burning device configured to read or write to a program burning interface. The program burning device includes a microprocessor, a programming drive circuit and an overcurrent protection circuit. The microprocessor outputs a first test signal or a second test signal. The programming drive circuit outputs a high driving voltage or a low driving voltage to the program burning interface. After the programming drive circuit outputs the low driving voltage for a preset time, the programming drive circuit outputs the high driving voltage to make the program burning interface form a high impedance. Afterwards, the overcurrent protection circuit receives the first test signal to trigger the overcurrent protection, and then receives the second test signal to trigger the undercurrent protection. If triggering the overcurrent protection and the undercurrent protection are continuously failed over a preset number of times, the microprocessor determines that current protection is failed.

An input sensor short-circuit inspection method including: setting an inspection frequency for detecting a short-circuit of an input sensor comprising a plurality of electrodes; driving the input sensor in an inspection mode at the set inspection frequency; and detecting the short-circuit of the input sensor based on a capacitance charged between adjacent electrodes among the plurality of electrodes of the input sensor in the inspection mode.

An apparatus for smart frequency selection in a ground monitor apparatus is disclosed. The apparatus includes an energy measurement circuit that measures an energy level at a test frequency in an equipment grounding conductor between a load and a power source and an energy comparator that compares the measured energy level with an energy threshold. The apparatus includes a continuity signal circuit that injects a continuity signal with a frequency at the test frequency in the equipment grounding conductor at an energy level above the energy threshold in response to the energy comparator determining that the measured energy level is below the energy threshold. The continuity signal is an indicator for continuity of the equipment grounding conductor between the power source and load.