Abstract: A radio frequency (RF) sensor that measures RF current includes a substrate that has an inner perimeter that defines an aperture. A conductor extends through the aperture. Sensor pads are arranged on the aperture and are connected to form two sensor loops. The loops generate an electrical signal that represents RF current flow through the center conductor. Additionally, a plurality of circular conductive rings may be included in the RF sensor to generate a signal representing the voltage of the conductor.

Abstract: A method and an apparatus for dynamic signal switching with multiple measurement sources, for a merging unit in an electrical power system, said merging unit receiving at least two input signals from at least one current transformer measuring the same physical primary quantity. The method comprises a step of outputting from said merging unit, in a real-time mode, a digitized output stream of sampled values with the truest representation of the physical primary quantity, based on the actual values of the input signals.

Abstract: A system for monitoring and reporting power consumption in a branch circuit electrical panel is disclosed. The system uses split core transformers to sense current and voltage within the electrical panel. Each circuit within the electrical panel is sampled periodically. The periodically sampled voltages and currents are transformed into power consumption data. The power consumption data is communicated to a remote server computer. The remote server computer generates reports regarding the power consumption of the various circuits within the electrical panel. A remote computer may be used to access the reports from the server. Note that this abstract is presented to meet requirements of the USPTO. This abstract is not intended to identify key elements of the apparatus and methods disclosed herein or to delineate the scope thereof.

Abstract: A construction system for a current and/or voltage sensor (100), intended for use in combination with a busbar (B), extends along a longitudinal axis (Y), thus forming a proximal portion and a distal portion with respect to said busbar (B), and said sensor (100) comprises a solid body (110) of dielectric material intended to contain and/or incorporate electrical members, and more specifically a U-shaped conducting bar (120) extending longitudinally along its longitudinal axis (U-120) and one or more sensors (130/250/360/450/510-520/610) are placed in the proximity of said U-shaped conducting bar (120).

Abstract: A method and a current sensor for measuring current in a conductor are provided. The current sensor has a flexible coil having a first end and a second end and a mounting ring. The flexible coil is wrapped within the mounting ring to form a closed loop. The mounting ring has a first hole and a second hole drilled tangentially to an inner diameter of the mounting ring. The first end of the flexible coil extends through the first hole of the mounting ring and the second end of the flexible coil extends through the second hole of the mounting ring. The mounting ring has a channel therethrough that provides an access point so that the mounting ring can be easily flexed open or closed.

Abstract: A current detection circuit and a transformer current measurement system are offered, in which when elements and circuit, which cannot operate originally unless a transformer with small excitation inductance is used, are connected to a primary side of the transformer, even if the transformer, whose excitation inductance is large, is used, transformer current (primary current and secondary current) can be measured without deteriorating operations of the elements and circuit. [Means for solving] A current detector CT (current transformer) is in series connected to a primary winding 111 of a transformer 11, and an inductor La is in parallel connected to to a series connection of the current detector CT and the primary winding 111. And, secondary current I2 of the transformer 11 is measured based on a value of primary current IT detected by the current detector CT.

Abstract: A device for sensing electrical current or voltage in an electrical distribution system using an actively compensated current ratio transformer that includes a first magnetic core having a first permeability and a second magnetic core having a second permeability higher than the first permeability. A primary winding having P turns is coupled with the first and second magnetic cores, a measurement winding having M turns is coupled with the first and second magnetic cores so that current in the primary winding induces current in the measurement winding, and a sense winding having S turns is coupled with the second magnetic core. An amplifier coupled to the sense winding receives a voltage developed across the sense winding and produces a compensation current in response to the received voltage. The amplifier has an output coupled to the sense winding to feed the compensation current through the sense winding to reduce the voltage developed across the sense winding voltage to substantially zero.

Abstract: A phase canceling current transducer for a power meter includes an error correction unit including a memory for storing error correction factors. A data processing device of the error correction unit adjusts the output of the transducer to correct for phase and ratio errors produced by the transducer current transformer or to cause the transducer's output to mimic the output of another current transducer.

Abstract: A magnetic field sensor comprises a magnetic field sensing cell and a magnetic shield comprising at least two parts separated by an air-gap and surrounding the magnetic field sensing cell positioned in a cavity of the magnetic shield.

Abstract: A Rogowski sensor is provided for measuring a current of an electrical conductor. The sensor has a Rogowski coil, which has an electrical winding resistor, and an integration device which is connected to the Rogowski coil and is intended to generate an output signal which is proportional to the electrical current to be measured by the Rogowski sensor. The integration device is formed by the winding resistor of the Rogowski coil and a capacitance which is connected to the two winding connections of the Rogowski coil, and for the output signal from the integration device to be formed by the voltage applied to the capacitance.

Abstract: A faulted circuit indicator device for mounting on an overhead conductor cable for electrical power distribution systems to detect an abnormally high electric current therein includes a housing having an enclosure formed therein and current sensing circuitry for detecting the presence of the abnormally high electric current in the cable. An indication unit is responsive to the current sensing circuitry to produce a visual indication in the presence of the abnormally high electrical current. A clamping mechanism formed of a yoke and a pair of opposed pressure plates is disposed above the housing for securely mounting the cable therein to detect the abnormally high electric current. Compression springs are provided for resiliently urging the pair of opposed pressure plates upwardly for automatically trapping the cable in a fixed central position between the yoke and the pair of opposed pressure plates.

Abstract: A meter for recording voltage and current on a transformer has current sensors positioned on a housing such that the meter can be mounted to the terminals of the transformer. The device also includes two voltage leads which can be attached to the transformers terminals. An instrumentation module is contained in the housing and is coupled to the current sensors and the voltage leads, the instrumentation module being adapted and configured to record voltage and current measurements from the current sensors and voltage leads. The instrumentation module includes a signal processing module for processing the voltage and current signals to provide other information such as energy and accumulated in-phase current data. Finally, the device includes a communications module coupled to the instrumentation module for communicating the voltage and current measurements and the derived data to a remote user.

Abstract: A clamp jaw assembly for a clamp meter is provided. The clamp jaw assembly comprises a housing containing a clamp jaw core disposed within a shield. The housing, shield, and core of the clamp jaw assembly are configured to provide an extended creepage and clearance path from an exterior of the housing to a surface of the core.

Abstract: A combined measurement device for measuring current and/or voltage of an electrical conductor, comprising a supporting body, a current sensor housed inside the supporting body, and a voltage sensor located at least partially inside the supporting body. A shielding is positioned around the current sensor. The current sensor and the voltage sensor are mutually arranged so as the shielding shields at least partially both the current sensor and the voltage sensor against external electric field disturbances.

Abstract: A voltage isolation circuit. The input voltage Vin is connected to a primary winding of a transformer T1 through a current limiting resistor R1. R1 is preferably sized such that the current flow in the primary at nominal input voltage is approximately 1 milliamp. Transformer T1 is wound as a current transformer with a fixed ratio between the primary and secondary windings. Thus, when 1 mA flows in the primary winding, 1 mA will also flow in the secondary winding. An inverting operational amplifier will continuously attempt to drive its inverting input to a zero potential through resistor R2. The voltage at Vout produced by the op-amp is a faithful replica of the voltage at Vin, but scaled according to the values selected for R1 and R2.

Abstract: A device for measuring a current flowing in an electrical conductor. The device comprises a magnetic circuit coupled to an electrical conductor. The magnetic circuit has an air gap and a magnetic field sensitive component disposed in the air gap to measure a magnetic field generated by the electrical conductor. A control core has a control winding configured to control an effective length of the air gap when the control winding is energized. A magnetic shield at least partially encloses the magnetic circuit, the magnetic field sensitive component and the control core.

Abstract: A high frequency current transformer (HFCT) sensor for detecting partial discharges produced by a component is disclosed. The HFCT sensor includes at least one electrically conductive pattern formed on a substrate, where the substrate comprises multiple segmented regions connected by intermediate regions for folding along multiple fold lines between the segmented regions to form the HFCT sensor. A system for monitoring at least one component of an aircraft wiring system is also disclosed. The monitoring system includes at least one of the HFCT sensors for detecting partial discharges produced by the aircraft wiring system component. The monitoring system further includes a data acquisition system configured to monitoring signals from the HFCT sensor(s).

Abstract: An exemplary embodiment includes a system for measuring and controlling a thyristor comprising a thyristor, a Rogowski coil in operable communication therewith the thyristor, and a processor operative to receive signals from the Rogowski coil, determine a direct current value of the thyristor, and control the thyristor.

Abstract: An apparatus for online partial discharge testing includes a split-core radio-frequency current transformer sensor, an actuation subassembly, and a biasing member. The current transformer sensor has a first portion, a second portion, and a sensor hinge operably engaged between the first portion and the second portion. The actuation subassembly includes an elongate first member secured to the first portion of the current transformer sensor, a second member secured to the second portion of the current transformer sensor and configured to be movable relative to the first member, and a third member engaged with the second member and configured to be movable relative to the first member. The biasing member is configured to pivotally bias the first portion and the second portion of the current transformer sensor toward each other relative to the sensor hinge, with the biasing member secured relative to the first member.

Abstract: Relay devices, systems and methods for obtaining an accurate representation of a current monitored with a Rogowski coil, without integration of the Rogowski coil output voltage signal in the time domain.

Abstract: The present invention provides a current measuring apparatus having an improved structure to inhibit the possible adverse effect of a current in a different phase and the possible generation of an induced electromotive force caused by a measurement target current, enabling the measurement target current to be accurately detected even with the small size of the apparatus.

Abstract: A method and system for measuring electric current in a plurality (n) of conductors. According to the invention, the method comprises the following steps: an electric current transducer is place substantially opposite to each conductor (I, i=1, . . . , n); a decorrelation matrix ([G]), which is a function of the position of the transducers in relation to the conductors, is constructed; the current (Imesi) in each conductor (i) is measured with the aid of electric current transducers and real currents (Iréeli) are deduced with the aid of the decorrelation matrix ([G]) and the measured currents (Imesi).

Abstract: A method of manufacturing a clamp jaw assembly for a clamp meter is provided. The method includes providing a clamp jaw core and a shield having a channel. The method further includes positioning the clamp jaw core within the channel of the shield such that the shield surrounds a portion of the clamp jaw core. The method also includes enclosing the clamp jaw core and the shield within a clamp jaw housing.

Abstract: A method, device and computer program product for determining at least one property of a current (Ip) running through the primary winding of a transformer operating in saturation using an unreliable detected current (Is) running through the secondary winding of the transformer. According to the invention a first reliable extreme point (EP1) of a cycle of the current in the secondary winding is detected and compared with an absolute time reference. Based on the comparison a first property of the current running through the primary winding in the form of the phase angle is then determined.

Abstract: A current measurement device is configured to measure electrical current in a primary conductor that is electrically insulated from the current measuring device. The current measuring device includes a transformer with a saturable magnetic core formed with a central aperture and a current measuring circuit. The electrical conductor in which electrical current is to be measured is disposed in the central aperture of the magnetic core. The current measuring circuit includes a current source driven by a voltage ramp generator that is connected to the secondary winding in a direction opposite the flow of electrical current in the primary conductor. When the magnetic flux in the transformer core is equal and opposite the magnetic flux generated as a result of the electrical current flowing in the primary conductor, the voltage of the voltage ramp generator is representative of the DC or AC electrical current flowing in the primary conductor.

Abstract: A clamp-on multimeter measures alternating current flow in an electrical conductor. The multimeter includes a display, a housing including the display, a first sensor, a second sensor, a processor and an integrator. The first sensor has a magnetizable material core and inductively senses the alternating current. The first sensor includes a first clamp portion fixed to the housing and a second clamp portion pivotally coupled to the first clamp portion. The second sensor includes a Rogowski coil that has a non-magnetic core and inductively senses the alternating current. The processor receives an input signal in a first voltage range and sends an output signal to the digital display. The integrator scales a signal from the second sensor in a second voltage range to the first voltage range. The housing includes the processor, the integrator, and a selector configured to select the input signal to the processor from one of the first sensor and the integrator.

Abstract: A clamp-on multimeter measures alternating current flow in an electrical conductor. The multimeter includes a display, a housing including the display, a first sensor, a second sensor, a processor and an integrator. The first sensor has a magnetizable material core and inductively senses the alternating current. The first sensor includes a first clamp portion fixed to the housing and a second clamp portion pivotally coupled to the first clamp portion. The second sensor includes a Rogowski coil that has a non-magnetic core and inductively senses the alternating current. The processor receives an input signal in a first voltage range and sends an output signal to the digital display. The integrator scales a signal from the second sensor in a second voltage range to the first voltage range. The housing includes the processor, the integrator, and a selector configured to select the input signal to the processor from one of the first sensor and the integrator.

Abstract: A current transformer is provided. The current transformer comprises an inner magnetic core having a central opening, an outer sense core circumscribing the inner magnetic core, at least one pair of conductors extending through the central opening and positioned symmetrically with respect to a center point of the inner magnetic core, and one or more coils disposed on the inner magnetic core, the outer sense core, or both, in a magnetically balanced configuration relative to a magnetic neutral axis of the inner magnetic core.

Abstract: A method for testing a line trap of the type whose blocking characteristics are a function of its resonant frequencies without requiring the line trap to be de-energized along with the transmission line to which the trap is connected by injecting a signal into the transmission line over a range of frequencies including at least one of the line trap's expected resonant frequencies; measuring the magnetic field strength produced by the current through the line trap's main coil and the total current flowing through the line trap, and computing the ratio of the magnetic fields where the ratio is computed over a range of frequencies that includes the expected resonant frequency(s) of the line trap, such that the resonant frequencies are indicated where said ratio is at a local maxima or minima.

Abstract: The present invention relates to a test apparatus for a broadband telecommunication network. The apparatus comprises an electrical DC power source having a first and a second electrical connection. The test apparatus further comprises a first electrical circuit comprising a first and a second electrical circuit input and a first and a second electrical circuit output. The first and second electrical circuit input are electrically connected to the first and the second electrical connection of the electrical DC power source respectively. Additionally electrical connection is established from the first electrical circuit input to the first electrical circuit output via a first inductor having a first inductance and electrical connection is established from the second electrical circuit input to the second electrical circuit output via a second inductor having a second inductance. A first impedance is transformer coupled to the first inductor.

Abstract: A method of designing a meter-mounted extender with a transformer is disclosed, wherein losses from primary and secondary windings are equalized for a given secondary load.

Abstract: A power sensor is disclosed for a current carrying conductor. In at least one embodiment, the sensor includes at least one ferromagnetic core, a secondary winding, and at least one of connecting elements for a load or a load. The secondary winding is designed as an injection molded part on an insulating layer that is injection molded onto the ferromagnetic core.

Abstract: A current sensor includes a coil for sensing current in a current carrying bus, and a mount for mounting the coil to the current carrying bus at a distance from the bus. A system including the current sensor includes similar structure.

Abstract: A power monitoring system that reduces the need for external power calculation devices while simplifying the configuration of power meters.

Abstract: In order to detect and evaluate changes in current as a result of electric arcs, a sensor signal, differentiated on the basis of time, is produced with a sensor-dependent frequency bandwidth whose upper cutoff frequency is 40 MHz and whose lower cutoff frequency is 100 kHz. The sensor signal is taken and an evaluation signal is produced with an upper cutoff frequency of less than or equal to 10 MHz. The evaluation signal is compared with a threshold value and a normalized signal is produced, and a pulse duration of the signal is extended to a prescribed time value.

Abstract: A current sensor is provided that employs a primary winding that carries the current to be measured, and a secondary winding that controls the flux inside the magnetic core, provides a sample of the primary current, and also helps to control the flux at small primary currents and to saturate the transformer. An auxiliary winding is optionally used to control the flux in order to simplify control of the sensor. By periodically applying a certain voltage at the secondary winding, the transformer core is forced out of saturation, and a sample of the primary current is taken by a sensing circuit that may include a sample-and-hold circuit and an analog-to-digital converter. A control circuit is employed to control the currents flowing in the secondary winding and optional auxiliary winding and to manage the sensing circuit.

Abstract: A double-clamp earth tester device, having a voltage-inducing transformer (VT) (30), a current-sensing transformer (CT) (32), a voltage source adapted to supply a voltage across a primary winding (31) on the VT core (44) and a signal processing unit (35) adapted to measure a resultant signal output from a secondary winding (33) on the CT core (46), is susceptible to errors induced by electromagnetic interference between the cores (44, 46) of the two transformers. Previously, the effects of this interference have been mitigated by surrounding one or both cores (44, 46) with electromagnetic shielding (42). This had lead to devices having a bulky head portion and attendant difficulties in accessing sites having restricted access (52). These problems have been overcome by providing means to modify the signal output form the secondary winding (33).

Abstract: This aims to provide a diagnosing device for detecting the measurements of an electric current, a voltage and a resistance by a temperature/moisture or pressure sensor or a signal state in control means, precisely with a simple circuit constitution, for diagnosing the soundness of a circuit while simplifying a power source circuit, to suppress the cost more than the conventional circuit having no diagnosing function, and for diagnosing the signal status in the measurement or control by a measuring means or a control means. An alternating voltage generating means containing a pulse-wave voltage and an alternating current is connected with the primary side of a transformer, and a driven member such as the measuring means for any of varying electric current, voltage and resistance is connected with the secondary side.

Abstract: A three-phase current sensor for measuring currents (IPH1, IPH2, IPH3) running in three conductors of a three-phase conductor system comprises a first magnetic measuring device (D1) and a second magnetic measuring device (D3). Each magnetic measuring device comprises a magnetic circuit provided with at least two interleaf gaps and a magnetic field sensor arranged in each interleaf gap. The magnetic measuring devices (D1, D3) are positioned on both sides of a central conductor or cavity, thereby enabling a central conductor to be inserted in such a way that one of three phases of the conductor system is formed.

Abstract: Apparatus and methods are provided for the measurement of power consumption at points of interest, such as circuit breakers, machines, and the like. Accordingly, means are provided for measurement of power consumption for each electrical sub-network that is controlled by a circuit breaker. Each apparatus is enabled to communicate its respective data, in an environment of a plurality of such apparatuses, to a management unit which is enabled to provide finer granularity power consumption profiles. Challenges of measuring relatively low supply currents, wireless operation in an environment of a large number of apparatuses, and self-powering are addressed.

Abstract: A current detection printed board includes: a board having a penetration hole that penetrates the board; and at least one wire that is formed in a coiled shape having both ends by penetrating the board along the periphery of the penetration hole and alternately connecting a front surface layer and a rear surface layer of the board, wherein, when a conductor, in which an AC current flows, is disposed to pass through the inside of the penetration hole, a current flowing in the wire is output through electromagnetic induction.

Abstract: A method and a current sensor for measuring current in a conductor are provided. The current sensor has a flexible coil having a first end and a second end and a mounting ring. The flexible coil is wrapped within the mounting ring to form a closed loop. The mounting ring has a first hole and a second hole drilled tangentially to an inner diameter of the mounting ring. The first end of the flexible coil extends through the first hole of the mounting ring and the second end of the flexible coil extends through the second hole of the mounting ring. The mounting ring has a channel therethrough that provides an access point so that the mounting ring can be easily flexed open or closed.

Abstract: A signal isolator for providing at an output thereof representations of input currents from a source provided in an input conductor supported on a substrate having a bridge circuit suited for electrical connection to a source of electrical energization with a pair of series circuit members electrically connected in parallel with one another supported on a substrate with each series circuit member having a magnetoresistive member electrically connected in series with a current value controller, controlled at a controller terminal, at an output terminal of that controller. Each magnetoresistive members is electrically isolated from the input conductor and has a resistance versus applied external magnetic field characteristic that is substantially linear for at least relatively small externally applied magnetic fields.

Abstract: The present invention is directed to a method of (1) providing continuous monitoring of various operating and environmental characteristics using RFID technology or similar wireless technology and (2) capturing data on historical events that have occurred on the circuits used for the transmission and distribution of electric power. The invention has the additional capability to communicate the information to operators at the site, in remote locations, or to other equipment (peer to peer). The invention provides a low cost method and apparatus to monitor and store operating characteristics and events on the electric power distribution circuit. The information can be used to reduce the duration of outages, for improving system reliability, to study the impact on the power grid of various environmental factors, to enhance the ability to react to operating conditions such as overloads, etc.

Abstract: An apparatus and method for current transformer adaptation for extending a distance between a current sensing location, having a load current carrying load conductor, and a current measuring location having a measuring instrument. A first current transformer adapted to being connected to the load conductor is used to sense the load current. Typically the distanced between the first current transformer and the current measuring instrument is limited by a load burden rating of the first current transformer and a pre-determined resistive load per unit length of an instrument conductor connecting the first current transformer and the current measuring instrument. The present invention provides for the distance to be extended by connecting a second current transformer, having greater load burden rating than the first current transformer, to a secondary winding of the first current transformer and connecting the instrument conductor between the second current transformer and the current measuring instrument.

Abstract: An ammeter is provided with a plurality of individual wound coils interconnected in a generally U-shaped array to measure the magnitude of current in a conductor extending through a sensing region inside the U-shape. Additional pairs of position-sensing coils determine the position of the conductor relative to the sensing region and provide outputs to circuitry which permits the magnitude measurement to be displayed only if the conductor extends through the sensing region.

Abstract: To provide a structure capable of securing satisfactory induction coupling efficiency and high reliability in manufacturing an induction coupling apparatus used in power line carrier communication, the induction coupling apparatus having a magnetic core formed from a first core element part and a second core element part so that a gap would be formed between the core element parts, includes: a core parallel moving mechanism for carrying out relative and parallel movement of the first core element part and the second core element part in a direction that the length of the gap varies; and a predetermined gap length regulating member for limiting parallel movement in a direction that the first core element part and the second core element part approach each other to regulate the gap length to the predetermined gap length in the case that the core parallel moving mechanism is used for the parallel movement.

Abstract: Automatic test equipment is capable of performing a high-speed test of semiconductor devices, with a low cost and high efficiency. The automatic test equipment (ATE) comprises: an ATE body configured to electrically test semiconductor devices; a field programmable gate array (FPGA) controlling drivers and comparators on the ATE; an accelerator connected to an output terminal of the FPGA and that doubles an operating frequency of the FPGA; and a decelerator connected to an output terminal of the FPGA and that converts an operating frequency of data transferred from the semiconductor device to the operating frequency of the FPGA.

Abstract: A clamp meter is provided for measuring consumption of current and power of an electrical appliance. The clamp meter includes a power inlet port and a power outlet port that are in controlled connection with each other. A current detection element is arranged between the power inlet port and the power outlet port. When the power inlet port is connected to a power source and the power outlet port is connected to an electrical appliance to be detected, with the electrical appliance turned on, the current detection element detects and converts the current flowing through the power outlet port into a digital signal, which is displayed on a display device mounted on the clamp meter, whereby, through the data and information displayed on the display device, a user may get aware of the power consumption of the electrical appliance and abnormality of power consumption thereof.

Abstract: The current measurement apparatus comprises a Rogowski coil 20 comprising a wire or conductor which forms a coil 22 and returns through the coil 22 as a central conductor. The coil 22 and the central conductor are formed from a single conductor or wire and, therefore, no electrical join (for example, a solder join or crimp) is required at the end of the Rogowski coil. The wire 28 used to form the coil 22 and the central conductor 24 is insulated prior to forming the Rogowski coil. The insulated coating 30 provides better insulation between individual coils and also helps to provide a more even spacing between the coils.