Transient Or Portion Of Cyclic Patents (Class 324/102)
  • Publication number: 20100033164
    Abstract: A transient noise detection circuit for detecting a level of a transient noise voltage is disclosed. The transient noise detection circuit comprises a triggering circuit, a rectifying circuit, and a controller. The triggering circuit is coupled between a power rail and a ground node. When the triggering circuit receives a transient noise, the triggering circuit generates a triggering signal. The rectifying circuit comprises a rectifying unit and a current-limiting unit coupled in series. When the rectifying unit receives the triggering signal from the triggering circuit, the rectifying unit will be triggered by the triggering signal. The controller is coupled to a detection node between the rectifying unit and the current-limiting unit. The controller is used for determining the level of the transient noise voltage based on the voltage of the detection node.
    Type: Application
    Filed: August 7, 2008
    Publication date: February 11, 2010
    Applicant: TRANSIENT NOISE DETECTION CIRCUIT
    Inventors: Ming Dou KER, Wen Yi CHEN, Hsin Chin JIANG
  • Publication number: 20100026369
    Abstract: The invention relates to a method for monitoring whether or not the switching threshold of a switching sensor lies within a predefined tolerance region. The switching sensor comprises a signal input, to which an input signal is applied, and a signal output via which a switch output signal is emitted that can take a first value when the input signal is larger than the switching threshold and, otherwise, takes a second value. A modulator signal generated by a modulator (MD) is used as an input signal, characterized in that the modulator signal changes continuously or cyclically between an output value, which defines the upper limit of the tolerance region, and a test value which is smaller than the output value and defines the lower limit of the tolerance region. According to the invention, the switch output signal pulses at the rate of the modulator signal between the first and the second value when the switching threshold of the switching sensor lies within the tolerance region.
    Type: Application
    Filed: October 22, 2007
    Publication date: February 4, 2010
    Inventors: Matthias Hofmayer, Michael Kindermann
  • Publication number: 20090039867
    Abstract: In an embodiment, a method is disclosed that includes receiving a clock signal at a delay chain of a circuit device and determining a value of the clock signal at a selected point within the delay chain. The method also includes adjusting the selected point when the value does not indicate detection of an edge of the clock signal.
    Type: Application
    Filed: August 9, 2007
    Publication date: February 12, 2009
    Applicant: QUALCOMM INCORPORATED
    Inventors: Martin Saint-Laurent, Boris Dimitrov Andreev, Paul Bassett
  • Publication number: 20080252284
    Abstract: The invention relates to an electric machine comprising a stator (10), a rotor (11) and a device for measuring a current in said rotating electric machine feeding electric loads (14, 15). Said device is arranged between the stator (10) and the electric loads (14, 15) in such a way that it makes it possible to measure a current (11, 12, 13, 14) running therebetween.
    Type: Application
    Filed: October 17, 2006
    Publication date: October 16, 2008
    Inventors: Jean-Marie Pierret, Raymond Rechdan
  • Publication number: 20080204954
    Abstract: A system and method to evaluate characteristics of notches in sine wave type electrical signals. An example method includes measuring a voltage waveform. A reference waveform is derived from the measured voltage waveform. A series of threshold voltage values is determined based on corresponding voltages of the reference waveform. The voltages of the voltage waveform are compared with the corresponding threshold voltages. The presence of a notch is indicated when a voltage of the voltage waveform is lesser in magnitude than the corresponding threshold voltage.
    Type: Application
    Filed: February 26, 2007
    Publication date: August 28, 2008
    Inventor: Jon A. Bickel
  • Patent number: 7385384
    Abstract: A method for testing a reliable connection of an antenna includes a coil (L) or something similar connected to a reference potential on one side and to the output of an amplifier on the other side, a first capacitor (C2) arranged in a parallel position to the coil (1) and a second capacitor (C3) arranged between the terminal of the coil (1) and the reference potential. The method consists in emitting a signal by the amplifier, carrying out a first voltage measurement on the antenna terminal during a transient state, and in carrying out the second voltage measurement on the same antenna terminal in a steady-state condition. The method can be used for vehicle LF antennas.
    Type: Grant
    Filed: August 27, 2003
    Date of Patent: June 10, 2008
    Assignee: Continental Automotive France
    Inventor: Jacques Rocher
  • Patent number: 7248066
    Abstract: An apparatus for enabling the on-chip analysis of the voltage and/or current transition behaviour of one or more embedded nets of an integrated circuit independently of the fabrication process. The said apparatus comprises a Reference Step Generator (RSG) for providing programmable reference voltages or currents, a Step Delay Generator (SDG) for providing programmable delays, a Comparator (C) that receives the output of the reference step generator on one input, the output from the node under test at the second input, and a latch enable signal from the step delay generator, and provides a latched digital output in response to the comparison, and a controller that co-ordinates the operation of the reference step generator, Step Delay Generator and Latching Comparator to provide a transient response measurement.
    Type: Grant
    Filed: December 29, 2004
    Date of Patent: July 24, 2007
    Assignee: STMicroelectronics PVT. Ltd.
    Inventors: Ruchir Saraswat, Balwant Singh, Prashant Dubey
  • Patent number: 7187161
    Abstract: The present invention includes a system with a sensor to detect a change in one or more physical characteristics and provide a corresponding electrical sensor signal, a controller including a power source for the sensor, and transient suppression circuitry. This circuitry is coupled between the sensor and the power source of the controller, and includes a first thermistor to protect the sensor from a power surge from the controller and/or power source.
    Type: Grant
    Filed: July 11, 2003
    Date of Patent: March 6, 2007
    Assignee: Wabash Magnetics, LLC
    Inventor: Wendell Lee Wright
  • Patent number: 7180301
    Abstract: A device for sensing and capturing the state of a direct current electrical power line comprising a voltage comparator having a pair of inputs, one of the inputs adapted to be connected to the power line, the other input connected to an analog and digital I/O module for supplying a threshold voltage to the voltage comparator, a plurality of latches, an equal plurality of integrators having different time constants, each integrator connected between the output of the voltage comparator and one of the plurality of latches for supplying an integrated replica of the output from the comparator to the latch, the analog and digital I/O module also being connected to the plurality of latches for reading the states of the respective latches and for resetting any set latch, and a programmed computer connected to the analog and digital I/O module for controlling the operation of the analog and digital module and for logging the occurrence of the setting of a latch.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: February 20, 2007
    Assignee: The Untied States of America as represented by the Secretary of the Army
    Inventor: Mark W. Hynes
  • Patent number: 7039471
    Abstract: A device for calculating the steady state behavior of a controller includes an amount generating unit for generating the amount of deviation of the regulator, a first threshold value calculation unit that detects whether the amount of deviation of the regulator has fallen below a first threshold value and then starts a lag time delay unit, and a second threshold value calculation unit that detects whether the amount of deviation of the regulator has fallen below a second threshold value. A signal transmission unit transmits a ready message signal when the lag time delay unit has reached a predetermined lag time and the second threshold value calculation unit has detected that the amount of deviation of the regulator has fallen below the second threshold value.
    Type: Grant
    Filed: June 9, 2003
    Date of Patent: May 2, 2006
    Assignee: Rohde & Schwarz, GmbH & Co. KG
    Inventor: Thomas Kuhwald
  • Patent number: 6856127
    Abstract: A method and apparatus for identifying and analyzing high power dissipation peaks across a switching device. The method and apparatus include processing voltage waveform data associated with a switching device to determine switching edge and slope parameters for each of a plurality of switching cycles, and identifying those portions of the voltage waveform data associated with switch state transition portions of the plurality of switching cycles. For a plurality of the identified switch state transition portions, respective peak power levels are calculated using portions of the voltage waveform data temporally corresponding to the plurality of identified switch state transitions, and portions of current waveform data associated with the switching device temporally corresponding to the plurality of identified switch state transitions.
    Type: Grant
    Filed: July 25, 2003
    Date of Patent: February 15, 2005
    Assignee: Tektronix, Inc.
    Inventors: P. E. Ramesh, Srikrishna H. Nadig, Roger Lo
  • Patent number: 6831453
    Abstract: The magnitude of a pulse in a signal having both positive and negative polarity pulses (for example, a ternary PDH signal) is determined by measuring the magnitude of multiple samples of the signal. A reference level for the signal is determined from a plurality of these sample magnitudes, and the magnitude of a pulse in the signal is determined from the sample magnitudes and the reference level.
    Type: Grant
    Filed: November 13, 2002
    Date of Patent: December 14, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Colin Johnstone, Alexander John Stephen
  • Patent number: 6628113
    Abstract: A novel method of and apparatus for accurately measuring surge currents such as motor-starting inrush currents is provided. An input signal from a current sensor is monitored, and when the input signal changes and exceeds a predetermined threshold, a surge current is detected. The input signal is acquired over a predetermined time period by a fast sampling ADC, which converts the input signal into a series of digitized samples representative of instantaneous current values. These values are processed to compute average current or RMS current, which is then displayed.
    Type: Grant
    Filed: May 9, 2001
    Date of Patent: September 30, 2003
    Assignee: Fluke Corporation
    Inventor: Michael F. Gallavan
  • Patent number: 6583612
    Abstract: A reusable miniaturized detector that utilizes magneto-optic elements to detect the occurrence of an electrostatic discharge during the manufacture or handling of electrostatic discharge sensitive electronic components and circuit boards. The device may also be used to determine the polarity and magnitude of the electrostatic discharge. The device may be manually or automatically read, either by removing the device from the environment being monitored or continuously monitoring in situ. The device can also be configured to provide protection to some electrostatic discharge events which could damage sensitive components being monitored.
    Type: Grant
    Filed: January 5, 2001
    Date of Patent: June 24, 2003
    Inventors: James P. Karins, Niels F. Jacksen
  • Patent number: 6452373
    Abstract: A voltage transient recorder can detect lightning induced transient voltages. The recorder detects a lightning induced transient voltage and adjusts input amplifiers to accurately record transient voltage magnitudes. The recorder stores voltage data from numerous monitored channels, or devices. The data is time stamped and can be output in real time, or stored for later retrieval. The transient recorder, in one embodiment, includes an analog-to-digital converter and a voltage threshold detector. When an input voltage exceeds a pre-determined voltage threshold, the recorder stores the incoming voltage magnitude and time of arrival. The recorder also determines if its input amplifier circuits clip the incoming signal or if the incoming signal is too low. If the input data is clipped or too low, the recorder adjusts the gain of the amplifier circuits to accurately acquire subsequent components of the lightning induced transients.
    Type: Grant
    Filed: January 8, 2001
    Date of Patent: September 17, 2002
    Assignee: The United States of America as represented by the United States National Aeronautics and Space Administration
    Inventors: Pedro J. Medelius, Howard J. Simpson
  • Patent number: 6396255
    Abstract: A reusable miniaturized detector that utilizes magneto-optic elements to detect the occurrence of an electrostatic discharge during the manufacture or handling of electrostatic discharge sensitive electronic components and circuit boards. The device may also be used to determine the polarity and magnitude of the electrostatic discharge. The device may be manually or automatically read, either by removing the device from the environment being monitored or continuously monitoring in situ. The device can also be configured to provide protection to some electrostatic discharge events which could damage sensitive components being monitored.
    Type: Grant
    Filed: January 5, 2001
    Date of Patent: May 28, 2002
    Inventors: James P. Karins, Niels F. Jacksen
  • Patent number: 6333634
    Abstract: A radio-frequency power supply (1) and a matching box (2) are electrically connected with a coaxial cable (4) while the matching box (2) and a main unit (3) are electrically connected with a coaxial cable (5). Around the coaxial cable (5), a radio-frequency current transformer (6) is provided and an output signal from the radio-frequency current transformer (6) is given to an oscilloscope (7). In an apparatus using the radio-frequency power supply, with this constitution, a method for measuring a radio-frequency current can be provided, by which spurious components and frequency variation of the radio-frequency current can be measured simply and precisely at a low cost, without changing a series of communication paths, such as the coaxial cable, for the radio-frequency current.
    Type: Grant
    Filed: March 4, 1998
    Date of Patent: December 25, 2001
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Ryoden Semiconductor System Engineering Corporation
    Inventors: Kenji Haze, Kouji Sonda
  • Patent number: 6329651
    Abstract: Process for real time sorting of signals from several semi-conductor detection elements in which: a) during a calibration phase: amplitude data and signal rise time data are established for each event signal, a biparametric detection spectrum with amplitude and rise time data is acquired, a biparametric acceptance window corresponding respectively to an amplitude-rise time correlation is established, and b) during an examination phase: an amplitude, rise time data pair is established in real time for each event signal detected, the events are sorted in real time, selecting the signals according to whether their amplitude and rise time data are or are not within the window.
    Type: Grant
    Filed: March 1, 2000
    Date of Patent: December 11, 2001
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Corinne Mestais, Alain Chapuis, Franåoise Mathy, Loïck Verger
  • Patent number: 6291983
    Abstract: The invention is a broadband network monitoring system and method. The system has one or more RF carrier generators that generate one or more generator signals, called a reference signal, each of the generator signals having a generator signal frequency. One or more RF transient detectors sense a line signal on one or more broadband lines in the broadband network. Each line signal has one or more test signals applied by a remote RF carrier generator. Each test signal has a frequency equal to one of the reference signals. Each RF transient detector senses and compares the test signal and the reference signal in various ways to produce a transient indicator when the test signal and reference/generator signal are not the same. The transient indicator indicates that there may be a perturbation or some other problem in the respective broadband line. A controller is connected to each of the RF transient detectors and controls an RF switch and an analyzer.
    Type: Grant
    Filed: April 24, 1998
    Date of Patent: September 18, 2001
    Assignee: International Business Machines Corporation
    Inventors: Edward Payson Clarke, Jr., Robert Alan Flavin, Perwaiz Nihal, Geoffrey Hale Purdy, Norbert George Vogl
  • Patent number: 6211664
    Abstract: The invention relates to a device for measuring the rise time of the electronic component of a signal disturbed by electronic noise and whose signal-to-noise ratio is mediocre. It incorporates a differentiating circuit (C12, C11) having at least one resistor (r) and one capacitor (c) implementing a high pass filter for filtering the low frequency background noise of the signal from the detector and a discriminating circuit (C21, C22) incorporating a comparator (k) for performing a comparison with the filtered signal from the differentiating circuit and an offset voltage selected as a function of the noise level interfering with the signal from the detector.
    Type: Grant
    Filed: September 14, 1998
    Date of Patent: April 3, 2001
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Jean-Paul Bonnefoy, Olivier Monnet, Jean-Pierre Rostaing
  • Patent number: 6172496
    Abstract: A reusable miniaturized detector that utilizes magneto-optic elements to detect the occurrence of an electrostatic discharge during the manufacture or handling of electrostatic discharge sensitive electronic components and circuit boards. The device may also be used to determine the polarity and magnitude of the electrostatic discharge. The device may be manually or automatically read, either by removing the device from the environment being monitored or continuously monitoring in situ. The device can also be configured to provide protection to some electrostatic discharge events which could damage sensitive components being monitored.
    Type: Grant
    Filed: September 16, 1996
    Date of Patent: January 9, 2001
    Inventors: James P. Karins, Niels F. Jacksen
  • Patent number: 6121779
    Abstract: A bulk current injection (BCI) system and method for testing electromagnetic susceptibility of electrical apparatus includes an RF modulator in a BCI setup. The BCI setup with RF modulator injects high instantaneous currents with a very low, controllable duty cycle into a wire under test, thereby simulating an electromagnetic environment to which electrical equipment is exposed during an electrical transient event. The RF modulator provides an amplitude modulated envelope for removing undesirable transients. Injecting currents at selectable frequency, one frequency at a time, allows for frequency-amplitude electromagnetic susceptibility mapping for each major wire within an electrical apparatus.
    Type: Grant
    Filed: August 14, 1998
    Date of Patent: September 19, 2000
    Assignee: General Electric Company
    Inventors: Michael Joseph Schutten, William George Earls
  • Patent number: 6040689
    Abstract: The present invention is a current sensing method and apparatus wherein a current transformer producing a secondary current is disposed in communication with a conductor having a primary current desired to be sensed. A current analyzer in communication with the current transformer is adapted to estimate the primary current in the conductor based on the secondary current output waveform, even in the case where the secondary current is in saturation. In one embodiment, the current analyzer estimates the primary current in the conductor by capturing the secondary current waveform output from the current transformer, selecting a predetermined number of data points in an undistorted, region of the secondary current waveform, and estimating the primary current based on the selected data points.
    Type: Grant
    Filed: June 17, 1997
    Date of Patent: March 21, 2000
    Assignee: SSAC, Inc.
    Inventor: Andrew Gluszek
  • Patent number: 5973499
    Abstract: A method for testing electrical loads in a vehicle electrical system is provided, in which the loads, which are fed by a vehicle battery, are selectively switched on and off. The load-specific current consumption in the switched-on state is determined and assessed in each case. The battery voltage is measured immediately before and shortly after the switching-off of a previously switched-on load in order to determine the load-specific current consumption value from the load-specific battery voltage difference. The internal resistance of the battery serves indirectly as the measuring resistance, which is determined by loading the battery with a known load on a trial basis.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: October 26, 1999
    Assignee: DaimlerChrysler AG
    Inventor: Siegfried Schulmann
  • Patent number: 5973604
    Abstract: Lightning strikes on or proximate to an optical fiber cable may be detected via a lightning detector (18) that monitors the characteristics of voltage present on a metallic sheath (12) associated with the cable. The lightning detector (18) detects excessive voltage levels, spikes and/or frequency variations associated with a lightning strike and generates an alarm signal communicated to a central monitoring facility.
    Type: Grant
    Filed: October 28, 1996
    Date of Patent: October 26, 1999
    Assignee: AT&T Corp.
    Inventors: Hossein Eslambolchi, John Sinclair Huffman
  • Patent number: 5899960
    Abstract: A power monitoring system with associated signal processing and storage capabilities. Each leg of a three-phase power signal is simultaneously sampled on a plurality of channels to capture the instantaneous content of the power signal without time-skewing between the channels. In a further embodiment, the sampled data is converted into the frequency domain and parameters relating to the power quality of the power signal is derived from frequency-domain data.
    Type: Grant
    Filed: August 21, 1996
    Date of Patent: May 4, 1999
    Assignee: Reliable Power Meters, Inc.
    Inventors: Robert E. Moore, Frederic W. Nitz, Michael A. Gipe
  • Patent number: 5886429
    Abstract: A computer controllable testing and monitoring station forms short-term intervals of simulated alternating current power level disturbance, either undervoltage (sag) or overvoltage (swell). The station forms the short term voltage sags or swells so that their effects on sensitive equipment can be measured. The starting point of the sag or swell disturbance, as well as the time duration of the disturbance, can be accurately controlled.
    Type: Grant
    Filed: December 11, 1997
    Date of Patent: March 23, 1999
    Assignee: Board of Regents, The University of Texas System
    Inventors: W. Mack Grady, Ricardo Chan, Gregorio C-Y Chung, David Gerez, William Blane Leuschner, George P. Olson
  • Patent number: 5845231
    Abstract: A power monitoring system with associated signal processing and storage capabilities. An input signal is sampled and the samples are compared to a threshold to identify an impulse. The system analyzes the length of each impulse to dynamically adapt a memory storage size to store a number of samples occurring during an impulse period. In a further embodiment, the input signal must remain below a second threshold for a fixed number of samples before storing of the samples is terminated.
    Type: Grant
    Filed: August 21, 1996
    Date of Patent: December 1, 1998
    Assignee: Reliable Power Meters, Inc.
    Inventors: Robert E. Moore, Frederic W. Nitz, Michael A. Gipe
  • Patent number: 5819203
    Abstract: A power monitoring system with associated signal processing and storage capabilities. Historical data for an electrical signal is retained and displayed by dividing the electrical signal in the time domain into segments herein referred to as events. A detected disturbance of the electrical signal forms a boundary between two events. For each such boundary, the steady-state value of a signal parameter such as root-mean-square (rms) voltage is stored for the two events delimited by the boundary. Samples of the electrical signal immediately surrounding the boundary are stored so that disturbances of interest can be closely inspected.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: October 6, 1998
    Assignee: Reliable Power Meters, Inc.
    Inventors: Robert E. Moore, Frederic W. Nitz, Michael A. Gipe
  • Patent number: 5819204
    Abstract: A power monitoring system with associated signal processing and storage capabilities. Disturbances on an electrical signal are evaluated based upon a quality factor and the disturbance and associated quality factor are stored. Disturbances with the lowest quality factor are deleted from storage when the storage device becomes full.
    Type: Grant
    Filed: August 21, 1996
    Date of Patent: October 6, 1998
    Assignee: Reliable Power Meters, Inc.
    Inventors: Robert E. Moore, Frederic W. Nitz, Michael A. Gipe
  • Patent number: 5801952
    Abstract: A power monitoring system with associated signal processing and storage capabilities. Impulses that are superimposed on an alternating-current electrical signal are identified and evaluated based upon amplitude, duration, and phase position. Impulses that are not substantially similar to impulses on immediately preceding cycles of the input signal are recorded. In a further embodiment, if a series of substantially identical impulses occurs, a count of the number of impulses is stored, and detailed data is stored for only the first impulse in the series. In another embodiment, the impulses are ranked according to a quality factor, and data for the impulse with the lowest quality factor is deleted from a storage device when the device becomes full.
    Type: Grant
    Filed: August 21, 1996
    Date of Patent: September 1, 1998
    Assignee: Reliable Power Meters, Inc.
    Inventors: Robert E. Moore, Frederic W. Nitz, Michael A. Gipe
  • Patent number: 5717325
    Abstract: A multi-processing transient event detector for use in a nonintrusive electrical load monitoring system has been provided. Templates of transient pattern data associated with each electrical load which may be monitored are stored. Such templates are then used to match and correlate with the actual monitored transient pattern data at the load site. The decomposition in which time scales are changed is accomplished in parallel along with one or more parallel event detection processing modules for each decomposition.
    Type: Grant
    Filed: January 5, 1996
    Date of Patent: February 10, 1998
    Assignee: Massachusetts Institute of Technology
    Inventors: Steven B. Leeb, Umair A. Khan, Steven R. Shaw
  • Patent number: 5565781
    Abstract: A device for detecting the malfunctioning of a magnetron which operates at start-up with a high power setting P.sub.0, and which is connected to the terminals (21, 22) of the secondary winding (19) of a high-voltage transformer (8). This device includes a device for measuring (28) the peak voltage value sampled in the supply circuit, a device for storing (29) the voltage value measured at successive instants, a device for comparing (30) two successive voltage values giving, in the event of a difference in value, an excess signal (a-b), and a device for detecting (31) the excess signal suitable for sending a malfunction signal to a counting device in order to determine the frequency of the malfunction.
    Type: Grant
    Filed: January 10, 1994
    Date of Patent: October 15, 1996
    Inventor: Gilbert Dauge
  • Patent number: 5561605
    Abstract: In an electric circuit supplying AC line current to a load (30, 31) from an AC source (26) of given frequency providing repetitive cycles, arc detection is provided by sensing cycle to cycle changes in the AC line current. The AC line current is sampled with a harmonic notch filter (72) at a plurality of n phases .THETA..sub.1 through .THETA..sub.n during each of a plurality of m cycles of the AC source (26), to provide a plurality of currents I.sub.n,m, where n is the phase and m is the cycle. The differences (I.sub.n,m)-(I.sub.n,m-x), where x is a designated number of cycles, provide a plurality of current difference signals. The absolute values of these current difference signals ID are accumulated in a synchronous summer (94) over the m cycles. An arc indicative signal is generated in response to given conditions and given combinations of conditions (116) of the cumulative absolute current difference signals ID.
    Type: Grant
    Filed: May 10, 1995
    Date of Patent: October 1, 1996
    Assignee: Eaton Corporation
    Inventors: Joseph J. Zuercher, Charles J. Tennies
  • Patent number: 5541502
    Abstract: A level measuring set for low-frequency signals with superimposed direct voltage includes a low-pass filter, a measuring rectifier, and a subtractor. A low-frequency measurement signal is supplied to the low-pass filter, which outputs a reference potential (U.sub.B) which corresponds to the direct voltage. The reference potential (U.sub.B) is applied to a reference point of the measuring rectifier. The measuring rectifier forms a positive and a negative direct voltage component (+U.sub.M, -U.sub.M) superimposed on the reference potential (U.sub.B) for the positive and negative half-waves of the low-frequency signal, respectively. The subtractor receives at inputs thereof the positive and negative direct voltage components (+U.sub.M, -U.sub.M) superimposed by the reference potential (U.sub.B) and emits a level measurement value of the low-frequency measurement signal.
    Type: Grant
    Filed: February 13, 1995
    Date of Patent: July 30, 1996
    Assignee: Siemens Aktiengesellschaft
    Inventor: Klaus Hoffmann
  • Patent number: 5483153
    Abstract: The present invention provides a transient event detector for use in a nonintrusive electrical load monitoring system at a monitored site having at least one electrical load. The transient event detector includes a data acquisition portion for acquiring and storing start-up power transient pattern data associated with each electrical load being monitored; a monitor for continuously monitoring total power load pattern data at the site; and a processor for correlating the transient pattern data to the total power load pattern data in order to identify each electrical load.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: January 9, 1996
    Assignee: Massachusetts Institute of Technology
    Inventors: Steven B. Leeb, James L. Kirtley, Jr.
  • Patent number: 5471134
    Abstract: The invention relates to measuring apparatus for measuring the real load factor on an electricity source delivering an AC current to a consumer appliance, said apparatus comprising:a current sensor supplying a signal that is continuously proportional to the current delivered by the source;a rectifier circuit receiving said signal and supplying a rectified signal;a peak detector circuit receiving the rectified signal and extracting therefrom the peak value, which peak value can be read on an indicator; andcalibration means enabling the measuring apparatus to be set so that the peak value indicator displays 100% when the measured peak value of the AC current reaches the specified maximum level.
    Type: Grant
    Filed: November 24, 1992
    Date of Patent: November 28, 1995
    Assignee: Saft
    Inventors: Jean-Claude Oudille, Antonio Veiga
  • Patent number: 5461306
    Abstract: A system for detecting the presence of an average dc current component in a load comprising a current transformer 10 for supplying a signal representative of the current, and a comparison means 12 and 13, for example a microprocessor and associated RAM, for comparing values of the current taken at time intervals corresponding to a phase interval of substantially n.pi., where n.pi. is an odd integer, of the ac periodic supply signal, so as to determine the presence of a dc current component caused by rectification of the supply. In one embodiment, the signal from a voltage detecting means 14-18 can be used to synchronise the sampling of the current at the correct phase.
    Type: Grant
    Filed: December 28, 1993
    Date of Patent: October 24, 1995
    Assignee: Schlumberger Industries, Inc.
    Inventor: Rex Niven
  • Patent number: 5452223
    Abstract: In an electric circuit supplying AC line current rent to a load (30, 31) from an AC source (26) of given frequency providing repetitive cycles, arc detection is provided by sensing cycle to cycle changes in the AC line current. The AC line current is sampled with a harmonic notch filter (72) at a plurality of n phases .THETA..sub.1 through .THETA..sub.n during each of a plurality of m cycles of the AC source (26), to provide a plurality of currents I.sub.n,m, where n is the phase and m is the cycle. The differences (I.sub.n,m)-(I.sub.n,m-x), where x is a designated number of cycles, provide a plurality of current difference signals. The absolute values of these current difference signals ID are accumulated in a synchronous summer (94) over the m cycles. An arc indicative signal is generated in response to given conditions and given combinations of conditions (116) of the cumulative absolute current difference signals ID.
    Type: Grant
    Filed: August 20, 1993
    Date of Patent: September 19, 1995
    Assignee: Eaton Corporation
    Inventors: Joseph J. Zuercher, Charles J. Tennies
  • Patent number: 5444459
    Abstract: A signal acquisition system using an ultra-wide time range digitizer with variable time interval data sampling and data storage includes signal conditioning and sampling stages, a digitizing stage for generating digital representations of a signal, and a memory for storing the digital representations. Timing circuitry controls sampling and digitizing which may be varied so as to acquire signals on linear, logarithmic, or other time bases. Signal compression may be obtained by digitizing information only when a desired change rate is observed. A display allows acquired signals to be displayed in linear, logarithmic or other manner.
    Type: Grant
    Filed: June 22, 1993
    Date of Patent: August 22, 1995
    Assignee: Zeelan Technology, Inc.
    Inventor: Hiro Moriyasu
  • Patent number: 5399964
    Abstract: A peak amplitude detector for use in a synchronized position demodulator associated with a linear variable differential transformer. The peak amplitude detector adjusts for phase shift in the transformer and maintains the full bandwidth of the transformer. The detector obtains the maximum positive or negative amplitude of the sinusoidal signal at one of the secondary windings of the transformer by first counting either a positive or negative half cycle of the signal and then while down counting one half of the counted half cycle sampling the amplitude of the sinusoidal signal. The sampling ends when the count reaches zero.
    Type: Grant
    Filed: August 23, 1993
    Date of Patent: March 21, 1995
    Assignee: Elsag International N.V.
    Inventor: Allan C. Zoller
  • Patent number: 5373242
    Abstract: A device for detecting and indicating a fault current flowing through a lightning arrestor or an insulator, the current being DC or at AC mains frequency, the device being housed inside a box that is provided with a frangible window and that has a piece of metal electrically connected to an end fitting of the lightning arrestor or of the insulator passing therethrough. The device has: a transformer for transforming the current, the primary of the transformer being constituted by the piece of metal, and the secondary of the transformer being connected to a peak-limiting circuit to make pulses of current due to surges corresponding, in particular, to lightning strikes inoperative; a heating resistance fed by said transformer and constituting an igniter for a pyrotechnic composition in which it is embedded, the composition being designed to break the frangible window; and preferably indicator means suitable for being released by rupture of the frangible window.
    Type: Grant
    Filed: March 29, 1993
    Date of Patent: December 13, 1994
    Assignee: Sediver Societe Europeenne d'Isolateurs en Verre et Composite
    Inventors: Rene Joulie, Rene Parraud, Serge Tartier
  • Patent number: 5325047
    Abstract: A voltage monitoring apparatus for monitoring a value of a rectified AC voltage applied across a capacitive load is disclosed. The voltage has an AC component and a DC component. The apparatus monitors the value of the rectified cyclical AC voltage at a selected portion of the cycle. The voltage to be measured can either be the instantaneous value of the voltage at a predetermined time in the cycle, or the RMS value of the entire cycle. The apparatus is especially useful for monitoring a cathodic protection voltage applied to a metallic structure in contact with the ground and subject to corrosion, such as often applied to an underground pipeline. Such voltage is typically full wave rectified AC, and it is beneficial to know if the minimum voltage value of each cycle applied to the pipeline is below a predetermined value.
    Type: Grant
    Filed: August 17, 1992
    Date of Patent: June 28, 1994
    Assignee: After Zero Technology Corporation
    Inventor: Marvin Kempton
  • Patent number: 5317251
    Abstract: A peak current detecting and non-volatile storage device has a substrate having a hole. Individual magnetic field detecting elements are located on the substrate and are radially displaced from the hole. A conductor extends through the hole. The magnetic field detecting elements are magnetized to a predetermined state. Current carried by the conductor creates a magnetic field around the conductor which alters the predetermined state of magnetization of the magnetic field detecting devices. Various readout techniques may be used to determine the altered state of magnetization which is representative of the magnetic field and may be easily related to the current.
    Type: Grant
    Filed: November 23, 1992
    Date of Patent: May 31, 1994
    Assignee: Honeywell Inc.
    Inventors: Jeffrey S. Haviland, Donald R. Krahn, Robert W. Schneider
  • Patent number: 5270637
    Abstract: An impulse direction detector for AC power systems determines the direction of high-frequency impulses on an AC (alternating current) power line by measuring impulse parameters on each side of a low-pass filter inserted in series with the power line. The low-pass filter is formed by two capacitors and a series inductance. The series inductance is formed by placing a magnetic core around the power line. The impulse parameters are measured on either side of the magnetic core and are then transmitted to a microprocessor. The microprocessor determines if the impulse is above a threshold level and which side of the magnetic core the impulse originated from. The microprocessor then displays the direction of the impulse and communicates the result to other digital systems.
    Type: Grant
    Filed: July 22, 1992
    Date of Patent: December 14, 1993
    Assignee: Basic Measuring Instruments
    Inventors: Alexander McEachern, Richard Piehl
  • Patent number: 5243343
    Abstract: A signal acquisition system using an ultra-wide time range digitizer with variable time interval data sampling and data storage includes signal conditioning and sampling stages, a digitizing stage for generating digital representations of a signal, and a memory for storing the digital representations. Timing circuitry controls sampling and digitizing which may be varied so as to acquire signals on linear, logarithmic, or other time bases. Signal compression may be obtained by digitizing information only when a desired change rate is observed. A display allows acquired signals to be displayed in linear, logarithmic or other manner.
    Type: Grant
    Filed: December 3, 1990
    Date of Patent: September 7, 1993
    Assignee: Zeelan Technology, Inc.
    Inventor: Hiro Moriyasu
  • Patent number: 5214319
    Abstract: A pulse detector keeps track of the peak value of an analog input signal and clocks output data pulses into a flipflop and shift register at peak values thereof while it monotonically increases in magnitude for each polarity. The data input to the flipflop becomes logic zero once the analog input signal changes direction toward the opposite polarity, whereby the last output data pulse in the shift register corresponds to the maximum peak of the analog input signal during the given polarity.
    Type: Grant
    Filed: September 11, 1992
    Date of Patent: May 25, 1993
    Assignee: Motorola, Inc.
    Inventor: Behrooz L. Abdi
  • Patent number: 5170359
    Abstract: A method and apparatus for detecting transient episodes includes parallel connected transient episode detectors (peripheral devices) to measure short-lived disturbances concurrently, each uniquely associated in series with one of a multiplicity of analog sensors. A shared memory connects an object sensor with its uniquely associated transient episode detector. The transient episode detector outputs signals through a second shared memory to a host disturbance processor. The transient episode detector adaptively tracks and masks background noise through use of a noise statistics stack. The stack is operated in two different modes: initialization and update. In the initialization mode, the stack operates in a recursive sort from the bottom up to replace initial dummy data with ordered noise level peak value measurements. In the update mode, only new significant non-redundant noise level peak values which fall outside of a defined central normal range of the stack are used to update the stack.
    Type: Grant
    Filed: June 5, 1990
    Date of Patent: December 8, 1992
    Assignee: Presearch Incorporated
    Inventors: Robert L. Sax, Richard Kram
  • Patent number: 4999573
    Abstract: A visual indication of the location and duration of a measurement gate relative to the signal being measured is provided on a display. In response to a start gate signal measurements are initiated and a predetermined change is effected in the normally displayed visual indication of the signal being measured. In response to a gate close indication, measurements are terminated and the normally displayed visual indication is resumed. The normal and changed visual indications are effected by a display control signal produced by summing the signal to be measured and an event gate signal at a point in the circuit near where the event gate signal is generated.
    Type: Grant
    Filed: July 31, 1989
    Date of Patent: March 12, 1991
    Assignee: Hewlett-Packard Company
    Inventors: Atul Tambe, Michael Wilson
  • Patent number: 4991106
    Abstract: The apparatus and method of the invention are applied to the generation of alternating sample, dark, reference and dark beams for direction of the sample and reference beams into an integrating sphere which comprises detecting means and a reference source, for spectroscopic analysis of a sample contained in a sample cell which is operatively associated with the integrating sphere; to the generation of digital control signals attendant the generation of the beams; and to the processing of the multiplexed, sample analysis results analog data signal, as provided by the detecting means, by aligning a digital control signal therewith in time and further operating upon the thusly aligned data signal to precisely calculate the sample analysis results.
    Type: Grant
    Filed: March 2, 1983
    Date of Patent: February 5, 1991
    Assignee: Alfa-Laval AB
    Inventor: John Francis X. Judge