Abstract: The present invention relates to current measurement apparatus. The current measurement apparatus comprises first and second measurement devices with each of the first and second measurement devices being operative to measure current in a respective one of a live conductor and a neutral conductor substantially simultaneously. The current measurement apparatus is operative to make plural different determinations in dependence on the substantially simultaneous current measurements.

Abstract: This invention generally relates to cable compensation, and is particularly applicable to cable compensation for an AC-DC voltage converter. In one embodiment, a cable compensation apparatus for compensating voltage drop of a cable connected between an electrical power supply and an electrical device comprises: a first capacitor; a timer circuit to time a predetermined time period; a current source to supply to said first capacitor during substantially said predetermined time period a first current substantially proportional to an output current outputted by the power supply to the cable; and a control circuit to adjust an output voltage outputted by said power supply to said cable dependent on a voltage on said first capacitor. The compensation in some embodiments is programmable by means of a discrete capacitor component.

Abstract: Methods and apparatus relating to very large scale FET arrays for analyte measurements. ChemFET (e.g., ISFET) arrays may be fabricated using conventional CMOS processing techniques based on improved FET pixel and array designs that increase measurement sensitivity and accuracy, and at the same time facilitate significantly small pixel sizes and dense arrays. Improved array control techniques provide for rapid data acquisition from large and dense arrays. Such arrays may be employed to detect a presence and/or concentration changes of various analyte types in a wide variety of chemical and/or biological processes. In one example, chemFET arrays facilitate DNA sequencing techniques based on monitoring changes in hydrogen ion concentration (pH), changes in other analyte concentration, and/or binding events associated with chemical processes relating to DNA synthesis.

Abstract: Methods and apparatus relating to very large scale FET arrays for analyte measurements. ChemFET (e.g., ISFET) arrays may be fabricated using conventional CMOS processing techniques based on improved FET pixel and array designs that increase measurement sensitivity and accuracy, and at the same time facilitate significantly small pixel sizes and dense arrays. Improved array control techniques provide for rapid data acquisition from large and dense arrays. Such arrays may be employed to detect a presence and/or concentration changes of various analyte types in a wide variety of chemical and/or biological processes. In one example, chemFET arrays facilitate DNA sequencing techniques based on monitoring changes in hydrogen ion concentration (pH), changes in other analyte concentration, and/or binding events associated with chemical processes relating to DNA synthesis.

Abstract: Methods and apparatus relating to very large scale FET arrays for analyte measurements. ChemFET (e.g., ISFET) arrays may be fabricated using conventional CMOS processing techniques based on improved FET pixel and array designs that increase measurement sensitivity and accuracy, and at the same time facilitate significantly small pixel sizes and dense arrays. Improved array control techniques provide for rapid data acquisition from large and dense arrays. Such arrays may be employed to detect a presence and/or concentration changes of various analyte types in a wide variety of chemical and/or biological processes. In one example, chemFET arrays facilitate DNA sequencing techniques based on monitoring changes in hydrogen ion concentration (pH), changes in other analyte concentration, and/or binding events associated with chemical processes relating to DNA synthesis.

Abstract: Methods and apparatus relating to very large scale FET arrays for analyte measurements. ChemFET (e.g., ISFET) arrays may be fabricated using conventional CMOS processing techniques based on improved FET pixel and array designs that increase measurement sensitivity and accuracy, and at the same time facilitate significantly small pixel sizes and dense arrays. Improved array control techniques provide for rapid data acquisition from large and dense arrays. Such arrays may be employed to detect a presence and/or concentration changes of various analyte types in a wide variety of chemical and/or biological processes. In one example, chemFET arrays facilitate DNA sequencing techniques based on monitoring changes in hydrogen ion concentration (pH), changes in other analyte concentration, and/or binding events associated with chemical processes relating to DNA synthesis.

Abstract: Disclosed are apparatus and methodology for providing approaches to remove or reduce thermal drift of the magnetic sensitivity of Hall sensor devices, to improve the stability of resulting signals of interest. Samples of a particular signal or signals of interest having improved stability make for advantageous use in conjunction with electricity meters. At the same time, associated designs and related components have greater simplicity, for reduced complexity in implementation. Among alternative embodiments, a gating structure selected of various present alternative designs may be used to partially cover, to an intentionally selected degree, an active area of a Hall sensor, so that a zero-drift supply current value may likewise be selected so as to satisfy other criteria which may be applicable to use of the Hall sensor.

Abstract: In a signal processing system, a set of channel signals from an array of sensors of different operating characteristics are processed in calibration circuitry that calculates individual average values of the channel signals and calculates an average of the individual average values of channel signals as a reference value. Reciprocal calculators calculate reciprocal values of the individual average values of the channel signals. Scaling circuitry scales the reciprocal values by the reference value to produce a set of amplitude calibration signals and scales the channel signals by the calibration signals respectively. As a result, the channel signals are normalized by their own average values and scaled by the reference value to produce a set of calibrated channel signals.

Abstract: In a signal processing system, a set of channel signals from an array of sensors of different operating characteristics are processed in calibration circuitry that calculates individual average values of the channel signals and calculates an average of the individual average values of channel signals as a reference value. Reciprocal calculators calculate reciprocal values of the individual average values of the channel signals. Scaling circuitry scales the reciprocal values by the reference value to produce a set of amplitude calibration signals and scales the channel signals by the calibration signals respectively. As a result, the channel signals are normalized by their own average values and scaled by the reference value to produce a set of calibrated channel signals.

Abstract: A battery pack, and more particularly, a temperature compensated current measuring device which can accurately measure an actual current flowing in a circuit of a charging/discharging path in the battery pack. The temperature compensated current measuring device includes a conductor in which current flows, a temperature sensor disposed around the conductor to measure a temperature of the conductor, and a temperature compensated current detection circuit part electrically connected to two positions of the conductor to measure a voltage between the two positions, electrically connected to the temperature sensor to measure a temperature of the conductor, and measuring the current flowing in the conductor by using the measured temperature and the voltage as an input signal. Thus, it is possible to accurately calculate an actual charging/discharging current with the temperature compensated current measuring device and effectively control the charging capacity of the battery pack.

Abstract: A signal processing device having an adjustment unit for adjusting a time duration of each of a plurality of signals individually in accordance with an amplitude of the respective signal to thereby generate calibrated signals, and a combining unit for combining the calibrated signals.

Abstract: A calibration system for a generator set controller is disclosed. The calibration system may have a source of electric power, a controller in communication with the source and configured to monitor a parameter of the electric power and produce at least one output corresponding to the monitored parameter, and a power meter configured to measure the parameter of the electric power. The calibration system may also have a processor in communication with the source of electric power, the controller, and the power meter. The processor may be configured to direct electric power having a first test voltage from the source to the controller, and directly relate a value of the at least one output corresponding to the first test voltage and a value of the measured parameter to an offset error.

Abstract: This disclosure relates to an autosensitive detector and an autosensitive measurement system with a self-adjustable set-off value, and more specifically, to a probe for adaptation to an environmental parameter such as liquids adapted to reset its measured sensitivity each time the probe is enabled or turned on, which can be further desensitized by adjusting a sensitivity correction factor by a factor (F) within the range of 0.05<F<2.01 of the reset sensitivity or of up to ten times or ten percent of the reset sensitivity but most likely of 10 to 20% from the initial value using a remote control system such as a handheld programmer or programming function of the sensor board.

Abstract: A meter device for measuring electrical energy is provided. The meter device includes circuitry for measuring at least one parameter of electrical energy provided to the meter device. A storage device is provided for storing at least one calibration factor for compensating for errors associated with at least one of at least one external current transformer (CT) and at least one external potential transformer (PT) that operates on the electrical energy provided to the meter device. At least one processor is provided for processing the at least one calibration factor for adjusting the measuring for compensating for the errors when measuring the at least one parameter of electrical energy.

Abstract: In a signal processing system, a set of channel signals from an array of sensors of different operating characteristics are processed in calibration circuitry that calculates individual average values of the channel signals and calculates an average of the individual average values of channel signals as a reference value. Reciprocal calculators calculate reciprocal values of the individual average values of the channel signals. Scaling circuitry scales the reciprocal values by the reference value to produce a set of amplitude calibration signals and scales the channel signals by the calibration signals respectively. As a result, the channel signals are normalized by their own average values and scaled by the reference value to produce a set of calibrated channel signals.

Abstract: A correcting circuit includes a correction current synthesizer synthesizing a correction current based on an output signal of a sensor, a current adjuster adjusting a determining current which corresponds to a correction amount based on the correction current, and a correction voltage generator generating a correction voltage for correcting a voltage signal based on the determining current, so as to correct an output characteristic of a voltage signal output in correspondence to the output signal of the sensor.

Abstract: A calibration apparatus and method for a capacitive sensing device, in which a calibration capacitor device connects to the capacitive sensing device which is connected to an integration circuit that generates a voltage output and a latch output, a transforming circuit transforms a sensitivity calibration parameter into a pair of corresponding analog signal outputs, and an offset calibration parameter into a corresponding analog signal output, at least two first switches between the pair of corresponding analog signal outputs and a fixed potential according to system clock's levels, and at least a third switch switches between the corresponding analog signal output and another fixed potential according to the system clock's levels. The apparatus determines the switch between the pair of signal outputs according to the latch output.

Abstract: An improved power sensor having an input connector connected to an input port having a center pin and a ground side; an amplifier; first and second detectors; and a thermal stabilization system, including a thermal mass disposed between the ground side of the input connection and the detectors, a ground plane for holding the temperature of thermally sensitive components constant to within 2 degrees C., and a thermal impedance disposed between the center pin of the input port, preferably including a splitter and at least one DC capacitor, and a temperature sensor disposed on the ground plane.

Abstract: An improved power sensor having an input connector connected to an input port having a center pin and a ground side; an amplifier; first and second detectors; and a thermal stabilization system, including a thermal mass disposed between the ground side of the input connection and the detectors, a ground plane for holding the temperature of thermally sensitive components constant to within 2 degrees C., and a thermal impedance disposed between the center pin of the input port, preferably including a splitter and at least one DC capacitor, and a temperature sensor disposed on the ground plane.

Abstract: A method for calibrating a hands-free system is provided. The hands-free system comprising a hands-free unit and a mobile phone, the method comprising the following steps of setting up a connection between the hands-free system and a distant terminal via a mobile telephony network of the mobile phone, transmitting a predetermined test signal from one of the hands-free system and the distant terminal to the other of the hands-free system and the distant terminal, the predetermined test signal being provided in both the hands-free system and the distant terminal as reference test signal, comparing the received test signal to the reference test signal stored in the other of the hands-free system and the distant terminal, and determining the calibration parameters of the hands-free system in accordance with the comparison.

Abstract: An instrument including a device, a transducer and a calibration module is disclosed. The device produces a reference time and/or a reference frequency. The transducer converts the reference time and/or the reference frequency to a reference signal. The calibration module adjusts an output signal generated by the instrument and/or a result of a measurement taken by the instrument, based on the reference signal. A system including the instrument and a method of calibrating the instrument are also disclosed.

Abstract: An instrument including a device, a transducer and a calibration module is disclosed. The device produces a reference time and/or a reference frequency. The transducer converts the reference time and/or the reference frequency to a reference signal. The calibration module adjusts an output signal generated by the instrument and/or a result of a measurement taken by the instrument, based on the reference signal. A system including the instrument and a method of calibrating the instrument are also disclosed.

Abstract: A meter device for measuring electrical energy is provided. The meter device includes circuitry for measuring at least one parameter of electrical energy provided to the meter device. A storage device is provided for storing at least one calibration factor for compensating for errors associated with at least one of at least one external current transformer (CT) and at least one external potential transformer (PT) that operates on the electrical energy provided to the meter device. At least one processor is provided for processing the at least one calibration factor for adjusting the measuring for compensating for the errors when measuring the at least one parameter of electrical energy.

Abstract: A self-calibrating current sensor for sensing the state of the current passing through a load line enclosed within a housing comprises a sensor disposed adjacent the load line for sensing a current passing through the load line, the sensor having an output at which a signal indicative of the level of current passing through the load line is present, the sensor being positioned with the housing, a binary input circuit configured to generate at least one binary signal, the binary input circuit being configured to change the level of the at least one binary signal without the need of opening the housing, and a controller circuit having a first input coupled to the output of the sensor for receiving the signal indicative of the level passing through the supply line and having a second input coupled to the binary input circuit for receiving the at least one binary signal, the controller being configured to provide a signal indicative of the status of the current in the load line on an output.

Abstract: A switched mode power can use a digital controller to control the switching of the at least one switch of the switched mode power supply. The current through the power inductor can be estimated using a self-tuning digital current estimator.

Abstract: A controlling method and a device are disclosed to calibrate a pointer assembly of an air-core meter. The pointer assembly of the instrument includes a calibrating magnet, a cosine coil, a sine coil and a pointer. According to the polarity of the return-to-zero magnetic field established by the calibrating magnet, a compensating voltage is imposed on the cosine coil or the sine coil or both under either a voltage driving mode or a current driving mode. The compensating voltage establishes a compensating magnetic field to cancel the return-to-zero magnetic field. Therefore, without modifying the structure of the pointer set, the pointer has good linearity and is not affected by the calibrating magnet.

Abstract: A multimeter having measurement terminals and configured to receive measurement signals applied to the measurement terminals and a measurement value and also configured to receive communication signals applied to the measurement terminals and extract encoded information from the communication signals. The multimeter can be included in a multimeter communication system having a device coupled to the measurement terminals of the multimeter. The device is configured to generate communication signals having encoded information and provide the communication signals to the measurement terminals of the multimeter.

Abstract: A series of pulses may be driven down each drive channel, which creates a series of composite pulses at the output of the buffer. Each composite pulse is a composition of the individual pulses driven down the drive channels. Timing offsets associated with the drive channels may be adjusted until the individual pulses of the composite pulse align or closely align. Those timing offsets calibrate and/or deskew the drive channels, compensating for differences in the propagation delays through the drive channels. The composite pulse may be feed back to the tester through compare channels, and offsets associated with compare signals for each compare channel may be aligned to the composite pulse, which calibrates and/or deskews the compare channels.

Abstract: A signal processing device having an adjustment unit for adjusting a time duration of each of a plurality of signals individually in accordance with an amplitude of the respective signal to thereby generate calibrated signals, and a combining unit for combining the calibrated signals.

Abstract: This disclosure relates to auto-averaging RC time constant calibration are described. An auto-averaging calibration circuit includes two capacitor branches, where capacitors in the capacitor branches, charge and discharge alternately to accommodate multiple charging cycles in one measurement cycle for measuring a RC time constant. A value of RC time constant is obtained in each charging cycle. A final value of the RC time constant can be determined by averaging various values of the time constants obtained during each charging cycle.

Abstract: A metering device for metering energy delivered to customers over electrical wires from a power distribution cabinet. The metering device has a plurality of current transformers, each capable of receiving one of the electrical wires and connections for the line voltages which drive the wires. The current transformers are arranged for physical correspondence to the power outputs of the power distribution cabinet. Circuitry connected to the current transformers and line voltage connections meter the energy over the electrical wires.

Abstract: Techniques for self-calibrating filtering circuits with feedback are described herein.

Abstract: An AC/DC voltage measuring instrument is operable in a DC mode, an AC mode, or an automatic mode. In the DC mode, an input terminal is coupled directly to an analog-to-digital converter, which generates a digital output signal indicative of the amplitude of the received signal. In the AC mode, the input terminal is coupled to an RMS circuit through a capacitor. The RMS circuit generates an output signal having an amplitude indicative of the RMS amplitude of the received signal, and this output signal is coupled to the analog-to-digital converter. In the automatic mode, the input terminal is also coupled to the RMS circuit, but it is coupled to the RMS circuit without being coupled through the capacitor. The input terminal is coupled to the RMS circuit through an amplifier, and a calibration procedure is used to compensate for any offset of the amplifier.

Abstract: A portable harmonics measurement instrument performs in-situ self-calibration of its current transducers and their associated measurement channels and of its voltage probes and their associated measurement channels. In-situ self-calibration is performed immediately before making a measurement on the alternating current power distribution grid. In-situ self-calibration is performed by means of a built-in voltage reference source and a built-in current reference source, which generate highly-accurate voltage and current calibration waveforms with harmonic components.

Abstract: A current sensing circuit has a transformer where a current to be measured induces a magnetic flux into a magnetic core. The magnetic core has a magneto-electric converter for sensing DC to low frequency current signals and a secondary winding for sensing higher frequency current signals. The magneto-electric converter generates an output that is coupled via an amplifier to a non-inverting input of a transimpedance amplifier. The inverting input of the transimpedance amplifier is coupled to the secondary winding of the transformer. A current signal path having a transimpedance resistor couples the inverting input to the output of the transimpedance amplifier. The transimpedance amplifier functions as a power amplifier for coupling a nulling current to the transformer for DC to low frequency current signals and functions as a transimpedance gain amplifier for higher frequency signals.

Abstract: A testing device for determines values of various electrical variables associated with a device within a process system. The testing device provides bi-directional electrical communication with a device to be monitored and automatically provides a connection configuration between a processing unit and a set of input/output ports. The connection configuration governs a bi-directional flow of electrical signals between the processing unit and the device to be monitored. The processing unit outputs a test signal and a configuration control signal to the input/output port control circuitry. The input/output port control circuitry, in response to received test and configuration control signals, automatically provides a connection configuration to direct the test signal to the device to be monitored and to direct a return signal, the return signal being generated by the monitored device in response to the test signal, to the processing unit.

Abstract: A ground fault detection system is provided where one current sensor is used to calibrate a second sensor in order to provide automatic zeroing of the difference measurement. The calibration is done gradually in order to differentiate between sensor drift and a transition in current due to a differential fault.

Abstract: An apparatus and method for on-chip bias measurement of an analog signals on an integrated circuit with a switchable analog-to-digital converter capable of performing testing and other types of processing. Analog signal test locations are selected for testing by a test input selector which is in turn controlled by a controller on an integrated circuit, such as an imager chip. Test locations are connected to one or more analog-to-digital converters through the test input selector. The analog-to-digital converter(s) output a test measurement digital output to either test equipment or an on-chip calibration circuit. Test equipment or on-chip calibration circuits adjusts imager component bias or other operating parameters used in chip or device operation based on output from the analog-to-digital converter(s).

Abstract: A self-calibrating test probe system that does not require probing head removal and replacement for calibration or may self-calibration is described. Using this system, the test probe and/or the entire system (including a testing instrument) may be calibrated or may self-calibrate while the probing head remains connected to an electrical component under test. A self-calibrating electrical testing probe includes a cable or signal path having a probing head at a first end and a connector at a second end. Calibration circuitry is preferably at least partially located in said test probe. The calibration circuitry preferably includes switch technology. The switch technology may be at least partially located in said probing head.

Abstract: A portable calibration unit for calibrating test equipment is disclosed that may incorporate a communication interface for connecting to a computer embedded within the test equipment, a variable signal source for producing a test signal, a processor in communication with the computer for controlling the variable signal source, and a test interface for communicating the test signal to the test equipment.

Abstract: A method and apparatus for calibrating an oscilloscope and storing the calibration results for further use. Accordingly, an oscilloscope is provided with a calibration cache database for storing various calibration curves and their associated states. Each time the oscilloscope is calibrated, the resulting calibration curves are stored in the cache. When the oscilloscope returns to a previously calibrated state, the corresponding calibration curves are simply loaded from the cache to recalibrate the oscilloscope. After some period of use, many or most states for the oscilloscope will have entries in the database, and revisiting these states will no longer require recalculating the calibration curves.

Abstract: A modular electronic utility meter has a sensor portion that includes sensor devices and a memory device storing calibration and/or error information specific to the sensor devices. Such a sensor portion is designed for use with a corresponding measurement portion that extracts the calibration and/or error information from the memory in the sensor portion. The measurement module then employs the calibration and/or error information in its calculation of energy consumption information. The calibration information includes phase and magnitude error information for at least one of a current sensing device and/or a voltage-sensing device. That error information may include coefficients of a polynomial.

Abstract: A system for coordinating the timing of a data strobe with data supplied by a memory module to the memory controller read data FIFO of a processor-based system, providing multiple calibration modes. A calibration PDL (programmable delay line) is used to reiteratively test the time taken for a test data strobe to traverse a portion of the memory controller circuit, and to generate a calibration value based upon the time taken. The calibration procedure may be initiated in any one of several modes, including: according to a predetermined schedule; implemented in software; in response to changes in environmental factors such as temperature or voltages sampled at one or more locations; in response to a software-driven trigger; or in response to a user-initiated trigger, communicated to a system of the invention either by input via a user interface to the processor-based system or by a software command.

Abstract: An offset calibration system of a control loop at least comprises a pre-amplifier circuit and a post-amplifier circuit. The pre-amplifier circuit generates a pre-output signal and then transmits the pre-output signal to the post-amplifier circuit to amplify. The offset calibration system comprises a comparator, an offset calibration module, and a determination circuit. The comparator compares the pre-output signal with a predetermined pre-reference signal to generate a pre-compared signal. The offset calibration module stores a predetermined and adjustable offset calibration value for adding to the pre-output signal. The determination circuit adjusts the offset calibration value based on the pre-compared signal, so the offset calibration value can be added to the pre-output signal dynamically to compensate and calibrate the offset of the pre-output signal caused by the pre-amplifier circuit to avoid the post-amplifier circuit amplifying the offset of the pre-output signal again.

Abstract: A current sensing device and a residual current detection device are described having a temperature compensation capability so that residual current can be directly measured to a high degree of precision in the background of a high load current. The residual current device comprises a plurality of resistive shunts for connection in respective ones of a plurality of lines through which current can flow to and from a load, and a detector means sensitive to the voltage developed across each of the shunts to detect any imbalance between the currents flowing through the shunts.

Abstract: A system for measuring differences in a physical variable, such as temperature or voltage, by utilizing predictable behavior in the relative time drift of offset curves for various circuit elements, including, for example, two sensors coupled to a difference signal amplifier, an ambient condition amplifier, and an analog to digital converter. In an initial calibration mode, the system records several offset curves, stored in memory, correlating ambient condition measurements to offset measurements acquired from the ambient condition amplifier and the difference signal amplifier. Offset curves recorded in the initial calibration mode, correlating ambient condition measurements to measurements from the difference signal amplifier, include one curve recorded with both inputs of the difference signal amplifier held at equal potential and another curve recorded with both sensors held at the same value of the physical variable, over a given ambient condition range.

Abstract: An apparatus for sensing electrical current flowing in a conductor includes a toroidal core formed of a ferric material and having a slot defining an air gap, a Hall Effect sensor integrated circuit positioned in the air gap for sensing electrical current flowing in a conductor received in a central aperture of the core, and a housing enclosing the core and the integrated circuit. The integrated circuit can be programmed to set functions such as output offset, gain, temperature compensation and a current sensing range.

Abstract: An apparatus for measuring current carried by a conductor has a differential voltage amplifier having inputs for connection to the conductor at two spaced-apart points thereof, constituting the ends of a segment. A circuit which converts an output voltage of the amplifier into a current value incorporates a microcontroller associated with a programmable memory storing a calibration table in digital form.

Abstract: A circuit for evaluating electrical signals having a programmable adjustment is described. The circuit includes an analog output for signals that have been evaluated which can be used to program the adjustment.

Abstract: A device and a method of metering and displaying immediate and/or accumulated energy consumption at a place of consumption, such as electricity, water or heating consumption in a household, said device comprising a recording unit which records and sums an immediate energy consumption on the basis of regular measurements and stores there measurements for the calculation of an average consumption, a display comprising at least one display unit capable of displaying the relationship between an accumulated energy consumption and the calculated average consumption for a selected period of time on a percentage scale.