A method for use in a sensor includes generating a first signal by a first sensing module in response to a magnetic field associated with a rotating target, generating a base word based on the first signal, the base word including a first base bit that is generated by comparing respective components of the first signal, reversing a respective polarity of the first signal and offsetting the first signal, generating a test word based on the first signal, the test word being generated after the respective polarity of the first signal is reversed and the first signal is offset, the test word including a first test bit that is generated by comparing the respective components of the first signal, and setting a value of an error signal based on whether the test word matches the base word.

In a method for calibrating at least one sensor, wherein the sensor includes at least one piezoelectric element with at least one electrode, and wherein at least one electrode is embodied as a measurement electrode, it is provided as essential to the invention that an electrical excitation voltage is applied to at least one further electrode of the piezoelectric element, embodied as a calibration electrode, to create a mechanical deformation of the piezoelectric element, that the voltage induced by the deformation of the piezoelectric element is captured with at least one measurement electrode, and that the applied excitation voltage and captured voltage are compared.

A current transformer (CT) for the purpose of, for example, current measurement, that uses a power line as a first coil and a second coil for measurement purposes, is further equipped with a third coil. Circuitry connected to the third coil is adapted to measure a signal therefrom. The measured signal from the third coil is compared to a signal measured from the second coil and based on the results, internal CT parameters are determined allowing calibration of actual results to expected results thereby providing an improved accuracy. This is especially desirable when using the CT for measurement of the like of current or phase of the primary coil when measurements are adjusted using the newly determined calibration parameters.

A ground fault detection circuit can include a band-pass filter that can have a first node and a second node that can be coupled to an earth ground. The first node can be coupled to a local ground of an automatic test equipment (ATE) system for an electrical device that can be coupled via at least one wire to the ATE. The band-pass filter can be configured to pass and amplify a test current signal established at the first node in response to a coupling of one of a conductor of the at least one wire carrying the test current signal to the local ground, and a conductive element of the electrical device carrying the test current signal to the local ground. A fault alert signal can be provided to provide an indication of ground fault based on a comparison of the amplified test current signal.

A calibration system for magnetometers includes magnetometers configured to measure a magnetic field to be measured; a magnetometer holder fixedly mounted on the magnetometer holder; at least one magnetic field generating device having its position fixed relative to the magnetometers, and used to generate a calibration magnetic field distribution in a space to be measured; and a calculation device configured to calculate the magnitudes of magnetic field vectors at the positions of the magnetometers according to the calibration magnetic field distribution generated by the at least one magnetic field generating device in the space to be measured, receive measured magnitudes of the magnetic field vectors from the magnetometers, and calculate detection gain values of the magnetometers on the basis of the calculated magnitudes of the magnetic field vectors and the measured magnitudes of the magnetic field vector.

A system for measuring impedance which is tolerant of connection errors includes a measuring instrument and a relay plate. The relay plate includes a plurality of relay groups. A relay group comprises a first channel, a second channel, a third channel, and a fourth channel. The first to fourth channels are electrically connected to a conductive pin of the product. The relay board further comprises a first voltage interface, a second voltage interface, a first current interface, and a second current interface, the first voltage interface is electrically connected to the first channel, the first current interface is electrically connected to the second channel, the second voltage interface is electrically connected to the third channel, and the second current interface is electrically connected to the fourth channel, a control unit being able to switch between these when connected to obtain impedance measurements.

A method for detecting abnormity of a machine slot includes the following operations. A first failure rate is obtained. A second failure rate is obtained. A slot, of which the second failure rate is greater than or equal to the abnormity value, is marked as a target slot, and A slot, of which the second failure rate is smaller than the abnormity value, is marked as a control slot. An significance level of a difference between a failure rate of the target slot and a failure rate of the control slot in each day of the second time period is checked.

A current-measuring transducer device has a current transducer for measuring an electric current along a conduction path. The current transducer has a magnetic field-sensitive element for converting the magnetic field resulting from the current flow along the conduction path into at least one physical variable and a measuring device for measuring the physical variable. The current transducer device has a coil arrangement with at least one coil for simulating the magnetic field resulting from the current flow along the conduction path. There is also described a method for calibrating a corresponding current transducer and a computer program product for performing the calibration method.

A management system includes a first receiver receiving, at a predetermined time interval, a reference value of a reference power meter, a second receiver receiving, at an interval shorter than the time interval, a first measurement value of a first power meter closer to a power system than a merging point of a power line connected to a distributed power supply and a power line connected to a load device, a third receiver receiving, at an interval shorter than the time interval, a second measurement value of a second power meter for measuring power consumption of the load device, and a controller executing a first calibration process related to the first power meter based on a comparison between the reference value and the first measurement value and subsequently executing a second calibration process related to the second power meter based on the first measurement value and the second measurement value.

A management system includes a first receiver receiving, at a predetermined time interval, a reference value of a reference power meter, a second receiver receiving, at an interval shorter than the time interval, a first measurement value of a first power meter closer to a power system than a merging point of a power line connected to a distributed power supply and a power line connected to a load device, a third receiver receiving, at an interval shorter than the time interval, a second measurement value of a second power meter for measuring power consumption of the load device, and a controller executing a first calibration process related to the first power meter based on a comparison between the reference value and the first measurement value and subsequently executing a second calibration process related to the second power meter based on the first measurement value and the second measurement value.