Abstract: A method and apparatus capable of detecting a considerably high voltage of a power supply while preventing an increase in the size and cost of circuitry, an increase in the amount of heat being generated, and a reduction in the detection accuracy of the circuitry. The voltage of a power supply to be detected is divided by way of a voltage-dividing resistor array. An voltage-to-current converter converts a potential difference appearing across the second voltage-dividing resistor in the array into a primary current so as to correspond to the potential difference. The converted primary current flows through a primary winding and an energization resistor. A second magnetic flux develops in a magnetic core from a secondary current, which flows through the secondary winding from a current buffer on the basis of the voltage output from a hole element according to the primary current.

Abstract: Radio-interrogated surface-wave technology sensor, in which the sensitive element (12) is an impedance which is electrically connected as termination to a surface-wave structure (26) of the sensor.

Abstract: An integral meter and current transformer to measure single phase active and reactive energy, voltage and frequency in industrial, commercial and multi-family residential applications. The meter CT is the primary sensing element in a revenue metering system encompassing multiple meter CTs serially connected in groups in communication with data cores for collection and reporting of energy consumption. Numerous data cores may be networked to report to a central station which may be remotely interrogated over the network or dial up modem connection. The meter CT utilizes a split-core transformer with substantially overlapping fingers. Disengaging split-core sections of the meter CT enables it to be easily installed around a loaded conductor without the interruption of power to the load.

Abstract: An electricity meter contains analog/digital converters to transform input analog voltages and currents into sampled digital values. A first high speed processor derives auxiliary magnitudes from the sampled digital values without intermediate storage. The auxiliary magnitudes, which do not have any direct physical significance, are provided to a lower speed second processor, which utilizes the auxiliary magnitudes to determine various desired parameters and functions of the input voltages and currents.

Abstract: A multimeter having an elongated housing with a fixed recess for receiving a current-carrying conductor is provided. The multimeter is adapted to measure various parameters including a.c. and d.c. voltage, resistance, and a.c. current. On one end of the elongated housing of the multimeter is a C-shaped current sensor mounted around the fixed recess for measuring a.c. current in the current-carrying conductor and on the other end is a pair of test leads for measuring resistance, a.c. voltage, and d.c. voltage. The current sensor and the test leads provide input signals to an analog-to-digital converter (ADC) to obtain digital samples which are displayed as measurement results according to the selected measurement mode.

Abstract: An electricity measurement apparatus includes two spaced-apart parallel conductors through which current flows in the same direction inducing a magnetic field between the conductors. Two magnetic field sensors are disposed on each side of a first plane in which the conductors lie. The sensors are in a second plane that is substantially between the conductors and perpendicular to the first plane. An arithmetic processor processes signals from the sensors to provide a value representative of current flow. The provided value is substantially independent of the position of the second plane within the space between the conductors.

Abstract: An electricity meter includes a sensor supplied with a rectified A.C. supply signal, the sensor detecting the strength of magnetic field induced by current flow along a conductor and providing an output signal following a sine-squared relation with alternating positive and negative sign in each half cycle, the output signal being filtered to remove a component due to D.C. offset error.

Abstract: An electricity meter including a circuit which receives a first A.C. signal having a magnitude dependent on power passing through a conductor, and a mains A.C. signal. While the mains signal is positive, first pulses are generated at a rate dependent on the first A.C. signal. While the mains signal is negative, second pulses are generated at a rate dependent on the first A.C. signal. Pulses are counted over time, the sum of pulse counts being a measure of energy used.

Abstract: An electrical junction box includes an electrical circuit, a current sensor having a ferrite bead ring for generating a magnetic field according to a current flow in the electrical circuit and also having a Hall element for outputting a signal based on the magnetic field of the ferrite bead ring, and a connector section for mounting both the ferrite bead ring and the Hall element. The electrical circuit has a terminal inserted through the ferrite bead ring to extend toward an opposing connector associated with the connector section. Furthermore, the Hall element has an output terminal extending toward the opposing connector.

Abstract: The invention concerns an electrical current sensor comprising a magnetic circuit (3), with an air gap (3a), a winding (4) on the magnetic circuit in which a current to be measured flows, a magnetic field detector (5) arranged in the air gap, and a support plate (2) carrying an electrical circuit (6) configured to amplify an output signal from the magnetic field detector. The support plate (2) comprises a main part (21) and a lateral extension (23), the entire unit having an area cut away from the overall rectangular shape of the plate. The turns (4a) of the winding (4) are arranged at that area in such a way that the thickness of the sensor depends on the transverse dimensions of the winding.

Abstract: A magnetic field sensor has two flux concentrators which serve to strengthen a magnetic field to be measured and which are separated by an air gap. Two Hall elements are arranged outside the air gap in such a way that at least a part of the field lines which lead from the first to the second flux concentrator pass through the two Hall elements in approximately opposite directions. Such a magnetic field sensor is less sensitive to external interference fields. It is suitable for the measurement of very weak magnetic fields and also for use as a current and/or energy sensor.

Abstract: An electric current sensor employing a Hall effect generator to be used in measuring electrical currents flowing in a current carrying conductor including a printed circuit board, an amplifier, a control current source, a toroid core having a gap, a Hall effect generator, and first and second traces configured on the printed circuit board so as to be non-inductive when exposed to the impinging magnetic field concentrated by the toroid core across the gap and across the Hall effect generator. The non-inductive configuration of the first and second traces is composed of a plated through hole electrically coupling the first and second traces to form a loop having a loop area equal to zero that is perpendicular to the directional flow of the impinging magnetic field thereby preventing the generation of unwanted induced voltages in the current sensor.

Abstract: An input sensor voltage is stepped up to a predetermined sensor voltage by a step-up single power supply circuit 30. The voltage thus stepped up is supplied to a first differential amplifier circuit 40, a first current buffer 50 and a constant voltage circuit 60. Either first or second transistor in the first current buffer 50 is turned on in accordance with a voltage difference across a Hall element 3 provided in a gap in a magnetic core of a coil 1. A current proportionate to a voltage from the first differential amplifier circuit 40 is output from the output terminal of the first current buffer 50 through a secondary winding 1c, a resistor RL and the constant voltage circuit 60 in the direction opposite to that of the current in a primary winding 1b to balance a magnetic flux in the coil 1. The constant voltage circuit 60 maintains a voltage at its output at a reference voltage.

Abstract: An electric current sensor employing a Hall effect generator and a ferrite substrate to be used in the measuring of electrical currents flowing in a current carrying conductor comprising a toroid core having a first and a second gap, a Hall effect generator, a current source, an amplifier, and a trace configuration positioned on the substrate for electrically coupling the amplifier to the Hall effect generator. The toroid core and ferrite substrate forming the complete magnetic circuit for the flow of the magnetic field. The trace configuration thereby being routed so as to be exposed to the magnetic field in two different impinging directions so to compensate for any unwanted induced voltages from being introduced into the output voltage thereby achieving an improved transient response.

Abstract: An electrical device is capable of sensing both AC and DC current which is flowing through an electrical circuit. The electrical device bifurcates the current into separate paths, wherein impedance of each path has a constant relationship to each other. In a further embodiment, the electrical device includes a current sensor for measuring current flowing through the circuit. The sensor is of a type which does not introduce insertion loss.

Abstract: The invention concerns magnetic sensors and, particularly, a magnetic sensor arrangement for use in an electrical measuring device. In the device, magnetic sensors are provided within recesses formed in the arms of the device. The recesses are typically formed within laminations and act so as to shield the magnetic sensors from interference, whilst enabling them to detect a magnetic field of an electrical conductor placed between the two arms.

Abstract: A device is provided for measuring electric current having at least one probe sensitive to magnetic flux arranged in the air gap of an annular core through which at least one conductor of a current to be measured is intended to pass. A compensation winding is wound of the core and a measuring resistor is connected in series with the compensation winding. A circuit is provided for regulating the supply current to the compensation winding regardless of the direction of the current to be measured. The circuit is controlled by the output signal of the sensor which is sensitive to magnetic flux.

Abstract: A portable current measuring apparatus brings many current sensing devices close to a wire in order for the magnetic flux of the current within the wire to induce a current in the devices. The devices are arranged in a bridge circuit and connected with a signal source and a differential amplifier so that when the output of the devices is added by the amplifier the noise generated by magnetic sources is eliminated. The housing for the apparatus is small and light weight and includes a place for a portion of the current carrying wire to be positioned for current detection. Use of the apparatus does not require that the wire be cut, nor is it required that the apparatus become a permanent fixture of the circuit having the current carrying wire.

Abstract: A current probe (10) measures a signal current flowing in a conductor (12), which produces a signal flux (14) proportional to the signal current. The probe includes a pair of probe arms (16, 18) that straddle the conductor, a flux shunt (20), a pair of flux diverting arms (22, 24), and a flux link (26). A Hall-effect device (28) senses the amount of flux flowing in the flux shunt. A major portion of the signal flux flows in a preferential path (30) through the flux shunt while a minor portion flows in a flux diverting path (32). The ratio of the amount of the signal flux flowing in the preferential flux path to the diverting path depends on the reluctance in each path, which is determined by air gaps (27, 34). The Hall-effect device drives a current source (40) that provides a diverter current through a pair of flux diverting coils (42, 44) that are wound around flux diverting arms (22, 24) of the current probe.

Abstract: An improved laminated ferromagnetic FIG. 8 power meter core is provided. The core is fabricated from a plurality of ferromagnetic plates and is formed in the general shape of a FIG. 8. The central leg of the core has a cross-sectional area that is larger than the cross-sectional area of other parts of the core. The core gap, in which a Hall-effect sensor is located, has gap faces with chamfered or rounded over edges to reduce fringing and bypassing effects. The core is formed without discontinuous corners that can result in local saturation and, in use, accommodates electrical power conductors in an over-under looping relationship through the openings of the core to provide a more homogeneous magnetic flux within the core and thus more reliable metering. The overall result is a core with a higher saturation point and thus a wider dynamic range than prior art cores.

Abstract: A sensor contactlessly driven by a single power supply is disclosed. A current flows in a resistor R.sub.L through the secondary winding of a coil in the direction corresponding to the direction of magnetic fluxes generated in the coil in accordance with discharge or charge mode of a main battery. The input terminal of a voltage follower is connected to the voltage-dividing point of a series circuit including resistors R.sub.1 and R.sub.2 and a reference voltage control circuit. The reference voltage control circuit changes the input voltage of the voltage follower in accordance with the direction of the current flowing in the resistor R.sub.L. It follows therefore that the measurement range is switched in accordance with discharge or charge mode of the main battery, with the result that the overall measurement range can be widened in spite of the fact that only a single power supply +Vcc is used.

Abstract: The Hall-effect sensor HS' of the invention incorporated in a CMOS integrated circuit IC' is formed with a well 2' as the sensor active layer on a substrate 1'. Heavily doped regions 31', . . . , 34', in the well 2' are connected with sensor metal contacts 41', . . . , 44'. The upper plane S' of the substrate 1' is covered by a field oxide layer 5' the thickness thereof being between 0.8 .mu.m. and 1.0 .mu.m. Over the layer 5' in the region 50' surrounding the sensor contacts 41', . . . , 44', a polysilicon layer 6' is provided to block the disturbing influence of ions migrating in the field oxide layer 5'.

Abstract: A current sensor has a closed loop magnetic flux concentrating ferromagnetic core with a gap and a central aperture for receiving a conductor. A Hall generator is positioned in the gap and a secondary winding is positioned on a portion of the core. Current flow in the conductor creates magnetic flux in the core which energizes the secondary winding to provide a power output. Magnetic flux concentrated in the gap causes the Hall generator to output a sensing signal that is proportional to the magnetic flux which is proportional to the current flow in the conductor. The single core is used to simultaneously produce a sensing signal proportional to alternating or direct current flow in the conductor.

Abstract: A sensor of the type comprising a magnetic circuit coupled to the lead, wherein circulates the current to be measured and presenting an airgap wherein is arranged a Hall cell (3) and coupled to a compensation coil (5) supplied, as well as the Hall cell, by a unipolar current source (V.sub.+, earth), comprises a four-branch bridge supply circuit wherein the coil (5) is connected to form a diagonal. The current source and a measurement resistor (R) are mounted in series with said bridge circuit. The variable conduction elements (8, 9, 15, 16) are mounted in the four branches of the bridge and are so controlled as to cause a make-up current to circulate in the coil (5), in one direction or the other, as a function of the residual flow direction indicated by the Hall cell (3), through two respective opposite branches of the bridge circuit. The other two opposite branches being non-conductive.

Abstract: Electric current, flowing through a penetration conductor extending through a main housing, is detected by a non-contact current detection unit incorporated in the main housing. Connector housings are provided respectively at those portions of opposite sides of the main housing through which the penetration conductor extends, and opposite end portions of the penetration conductor as connector terminals are disposed within the connector housings, respectively. Each of the connector housings and the associated connector terminal received therein jointly constitute a connector.

Abstract: A method and an apparatus for sensing quiescent current in a CMOS integrated circuit. The present invention utilizes circuitry which is not series coupled to the CMOS integrated circuit under test. The quiescent current, commonly referred to as I.sub.DDQ, flows through the supply line during the quiescent state of the CMOS integrated circuit. A magnetic field sensor is located on the substrate near the supply line of the CMOS integrated circuit. The magnetic field sensor detects the magnetic field generated from the supply line by I.sub.DDQ. The magnetic field sensor is coupled to output circuitry located on the substrate which produces a measurement result calibrated to indicate when I.sub.DDQ has a predetermined value.

Abstract: A device for measuring an electrical quantity of a system under measurement including a Hall element equipped with a pair of current input terminals and a pair of voltage output terminals. In the Hall element, four equivalent resistances are formed. The device also includes a device for applying a magnetic field proportional to a value of a first current on the Hall element, and a current supply circuit for flowing a second current between the current input terminals. The device further includes an output circuit for detecting a first voltage appearing between the output voltage terminals and outputting the first voltage as a measured value corresponding to the electrical quantity, and an offset compensation circuit for detecting an offset appearing between the voltage output terminals for varying one of the four equivalent resistances based on the offset thus detected so as to compensate the offset.

Abstract: A shield member is placed in a case, and connector pins extend through respective through capacitors and are soldered to the shield member. A core is inserted in the case, and has an engaging member engaging an upstanding portion of the case, the core having a gap fitted over a ridge on the case. A printed-circuit board has positioning holes fitted over pins on the core. The connector pins have respective upper ends inserted through and soldered to through holes defined in the printed-circuit board. Attachment holes defined in the printed-circuit board are held in registry with threaded holes defined in an upper end of the upstanding portion of the case, and the printed-circuit board is fastened to the upstanding portion by screws threaded through the attachment holes into the threaded holes. A shield cover is bent over into alignment with an upper edge of the shield member, and teeth on the shield member are bent inwardly onto and soldered or spot-welded to the shield cover.

Abstract: For potential-free d.c. and a.c. measurement, a terminal for connecting live conductors with at least two clamping components for the electrical conductors and a connecting member securing the clamping components together has one or more magnet field sensors arranged at a predetermined distance from the connecting member securing the clamping components of the electrical conductors together.

Abstract: To locate ground faults in a normally ungrounded DC circuit a centertapped voltage divider is connected across the positive and negative buses. An oscillator controlled switch is connected between the centertap and ground which when operating modulates the ground fault currents with a square wave having a repetition rate no greater than 3 hertz. A Hall probe including a field nulling coil is clamped successively along the conductors under test. A capacitive storage circuit maintains the energization of the nulling coil at the level that provided a null indication immediately prior to actuation of a test button. The Hall probe is connected to a read-out oscilloscope which indicates the presence or absence of the square wave modulation. Fault currents as small as 1 ma can be detected.

Abstract: Machine operating conditions can be monitored by analyzing, in either the time or frequency domain, the spectral components of the motor current. Changes in the electric background noise, induced by mechanical variations in the machine, are correlated to changes in the operating parameters of the machine.

Abstract: A power calculating device including a control signal generating unit for generating a control signal. The control signal determines a power calculating period and an imbalance compensation period. The device also includes an input voltage changeover unit for changing over between a first voltage corresponding to a voltage of a system under measurement and a constant voltage under the control of the control signal to generate a second voltage, which is the first voltage during the power calculating period and the constant voltage during the imbalance compensation period. The device further includes a Hall element member for generating a third voltage corresponding to a product of the second voltage and a magnetic density generated by a magnetic field applied to the Hall element member. The device also includes an imbalance detecting unit for generating an offset compensation signal based on the third voltage, and a variable resistor connected to the Hall element member.

Abstract: A current probe comprising a Hall device and a secondary winding in a flux linking relationship with a magnetic circuit is self-calibrated by disconnecting the Hall device from the winding, passing a current through the winding so as to induce a magnetic flux in the magnetic circuit, measuring voltage developed by the Hall device in response to linking by the magnetic flux, calculating the Hall gain of the Hall device, and then adjusting the gain of a scaling output amplifier on the basis of the calculated Hall gain to compensate for variation in Hall gain due to changes in operating conditions.

Abstract: The present invention involves measurement of an electrical current by means of a current transformer having the current to be measured passing in an axial direction through the current transformer, and the voltage induced thereby in the windings of the current transformer are used to produce a first voltage. A Hall effect is used in series with the current transformer to produce a second voltage measurement corresponding to the current measured by the Hall effect sensor. When the two measurements agree to within a predetermined value (typically 5% of the root-mean-square current values measured by each sensor) then the current transformer reading is used as the more accurate. Otherwise, the Hall effect current sensor is used as the more accurate current measurement.

Abstract: An apparatus for driving a piston with fluid power is disclosed. The apparatus includes a fluid filled cylinder having an inner and an outer wall and defining a longitudinal axis. A piston is slidably positioned in the cylinder to move along a path of travel parallel to the longitudinal axis. A magnet is coupled to the piston for movement with the piston, The apparatus further includes a pump in fluid communication with the cylinder and being selectively actuated to intermittently pump pressurized fluid into the cylinder to apply force to and move the piston in a first direction along the path of travel. A fluid releasing apparatus is provided to release fluid from the cylinder to move the piston in a direction opposite the first direction. The apparatus also includes a Hall effect sensor situated at a location along the outer wall of the cylinder for sensing a position of the piston by sensing a magnetic field associated with the magnet at the location of the sensor.

Abstract: A current probe comprising a Hall device and a secondary winding in a flux linking relationship with a magnetic circuit is self-calibrated by disconnecting the Hall device from the winding, passing a current through the winding so as to induce a magnetic flux in the magnetic circuit, measuring voltage developed by the Hall device in response to linking by the magnetic flux, calculating the Hall gain of the Hall device, and then adjusting the gain of a scaling output amplifier on the basis of the calculated Hall gain to compensate for variation in Hall gain due to changes in operating conditions.

Abstract: A DC current sensor using a continuous annularly-shaped detecting core of soft magnetic material; a continuous annularly-shaped exciting core of soft magnetic material intersecting with the detecting core perpendicular to the plane thereof; respective detecting and exciting coils wound respectively around the detecting and the exciting cores; an AC excitation of a given frequency applied to the exciting coil to saturate the detecting core; a wire conducting DC current to be detected extending through the detecting core to establish a magnetic flux therein; and a detector connected to the detecting coil for detecting the magnetic flux modulated by the AC excitation to detect the DC current flowing in the wire.

Abstract: A first Hall element is supplied with a current proportional to a load voltage and applied with a magnetic field proportional to a load current and produces a voltage proportional to a load power given by the load voltage and the load current. A second Hall element has the same characteristic as that of the first Hall element and supplied with the current proportional to the load voltage and no magnetic field. The output voltages of the first and the second Hall elements are combined by combining means to compensate and remove an offset voltage component contained in the output voltage of the first Hall element.

Abstract: A current controller for controlling an input current carried by a primary conductor. The current controller has a gapped core of magnetic material magnetically coupled to the primary conductor, as for example by the primary conductor being wound around the core. A secondary conductor is magnetically coupled to the core of magnetic material in an opposite manner to the primary conductor such that current flowing in the secondary conductor generates a second magnetic field in the core opposed to the first magnetic field. A Hall effect latch is located in the air gap and has output voltage corresponding to a hysteresis function of the difference in the first and second magnetic fields.

Abstract: A power multiplication circuit including a Hall element for generating between voltage output terminals thereof a first output voltage corresponding to a power of a system under measurement. The circuit further includes a voltage polarity detection circuit for detecting a polarity of a power source voltage of the system and an operating circuit connected to receive the first output voltage and the polarity for amplifying the first output voltage and for changing over between amplified first output voltage and an inverted voltage of the amplified first output voltage to generate a second output voltage in accordance with the polarity. The circuit also includes an integrating amplifier circuit for integrating the second output voltage to generate an integrated signal and a variable resistance element connected between one of the voltage output terminals of the Hall element and ground, and connected to receive the integrated signal.

Abstract: A current sensor for measuring a primary electrical current inducing a magnetic flux density defined over a known region comprises: a first sensor for measuring magnetic flux due to the primary current over a first predetermined area included within the known region; and a second sensor for measuring magnetic flux due to the primary current over a second predetermined area within the known region, the magnetic flux due to the primary current measured by the second sensor being a substantially predetermined calibrated amount different from the magnetic flux due to the primary current measured by the first sensor. The current sensor may further include a current source for generating a current inducing a magnetic flux density within the known region to at least partially offset the difference between the magnetic flux due to the primary current measured by the first sensor and the magnetic flux due to the primary current measured by the second sensor.

Abstract: The present invention relates to an apparatus and a method for measuring the current in a high voltage overhead line (A). The apparatus comprises at least one device (2) for detecting and measuring the magnetic field induced by the line (A), the detector being arranged on the ground adjacent the line (A), the current being deduced by calculation.

Abstract: A current sensor is provided with a planar member formed within a first opening of the sensor housing and extending inwardly from an inner periphery of the housing. The planar member extends into the first opening and is provided with a second opening through its structure. The second opening formed in the planar member is shaped to permit a portion of an electrical conductor to extend therethrough. The planar member is captured between a portion of the electrical conductor and an external object in order to permit the current sensor to be rigidly retained in a predetermined position relative to the external object. This means of fastening a current sensor to an external object eliminates the need for additional rivets, screws and bolts that would otherwise be required to perform this function.

Abstract: An apparatus for measuring at least one state variable of a brushless direct-current motor includes 2 * n pole segments, wherein n=1, 2, 3, etc.. The pole segments are integral with a rotor of a brushless direct-current motor and are formed of permanently magnetic material generating a magnetic field. At least one Hall-effect element supplies an output voltage and is disposed in the vicinity of the rotor for impressing the magnetic field of the permanently magnetic segments on the output voltage from the at least one Hall-effect element. A logic unit receives the output voltage from the at least one Hall-effect element for determining the temperature of the brushless direct-current motor.

Abstract: An electric current sensor employing a Hall effect generator to be used in measuring electrical currents flowing in an electrical conductor. The sensor comprises an amplifier, a constant current source, a gapped toroid core mounted on the component side of a printed circuit board (PCB), a Hall effect generator extending via its output leads from the PCB into the gap of the toroid core, and an inductive loop positioned at the edge of the gap of the toroid core. The inductive loop itself comprises a simple trace formed on the component side of the PCB together with its plated-through-holes extending from the component of the PCB to the printed circuit (clad) side of the PCB. The PCB inductive loop placed at the edge of the gap of the toroid core and connected in series opposition to the output leads of the Hall effect generator, compensates for the unwanted induced voltages in the output leads of the Hall generator.

Abstract: A first Hall element is supplied with a current proportional to a load voltage and applied with a magnetic field proportional to a load current and produces a voltage proportional to a load power given by the load voltage and the load current. A second Hall element has the same characteristic as that of the first Hall element and supplied with the current proportional to the load voltage and no magnetic field. The output voltages of the first and the second Hall elements are combined by combining means to compensate and remove an offset voltage component contained in the output voltage of the first Hall element.

Abstract: A floating data interface, particularly for integrated circuits, is formed by a Hall-effect arrangement that includes a Hall-voltage-measuring device and a current-carrying coupling loop whose current is controlled by a data source. Because of the low internal resistance of the coupling loop, a plurality of such interfaces can be connected in series, and the individual circuits selected by addresses. Bidirectional data transfer via the floating interface is accomplished by an interrupter stage which interrupts the current flow on the bus line in an interrogation interval during one clock period and forces a predetermined mark/space ratio.

Abstract: An electrical power controller includes an integrated circuit having a Hall element, a Hall voltage amplifier, a ramp signal generator, and a voltage comparator. The output of the ramp generator is connected to one input of the voltage comparator and the output of the Hall voltage amplifier is connected to the outer comparator input. During intervals when the amplified Hall voltage exceeds the ramp voltage, the output of the comparator changes from one binary state to the other such that a stream of pulses is generated at the output of the comparator. Thus as a magnetic field at the Hall element increases, the Hall voltage increases and the width of each pulse in the stream of pulses grows proportionally. Mechanical means is provided for manually moving and guiding the pole of a magnet along a path toward the integrated circuit. Constructions of such controllers adapted for use as lamp dimmers and DC motor speed controllers are described.

Abstract: A current sensing system includes a number of remote current sensors for measuring the magnetic field surrounding each conductor of an electrical transmission system to independently monitor the current flowing through the conductors. A generally U-shaped mounting fixture is provided for supporting the current sensors in a fixed, predetermined orientation relative to each of the conductors. An electronic compensation circuit is provided for conditioning the output of each the sensors with the output of the other of the sensors to isolate the influence of the magnetic field induced by the current flowing through only one of the conductors.

Abstract: An electric current detecting apparatus having gaps in a looped core and a primary winding and a secondary winding around the looped core. The gaps have continuous portions in the looped core. A magnetoelectric transducer such as a Hall effect element is inserted into at least one of the gaps. The gaps and the secondary windings have the same dimension as well as the same shape and are symmetrically arranged to reduce damping oscillation and transient spike noise of the secondary current I2. The continuous portion prevents increase of magnetic reluctance of the core. The electric current detecting apparatus has good high frequency response characteristics and detects a large current of a square wave pulse at a high speed and with high fidelity.