Abstract: The invention is a neutral atom (and/or molecule) matter-wave interferometer (and/or set of interferometers) that can be used as an inertial sensor with a sensitivity exceeding that of conventional mechanical sensors and multiple circuit optical interferometers (including ring lasers) by many powers of ten. An interferometer in which matter-wave propagation beam paths enclose a finite area will sense rotations via the Sagnac effect. One with the paths displaced from each other will sense acceleration plus gravity. Interferometers with paths that follow a figure-eight pattern yield a gravitational gradiometer. Laser cooling and slowing of a beam of neutral atoms provides a low energy nearly monochromatic source. Diffraction gratings are employed as beam splitters. Such gratings may consist of apertures in a sheet of solid material, near-resonant standing-wave laser beams, or crystal faces.

Abstract: A sensor (1) for sensing the magnitude of current flowing in a conductor (12) based upon the Faraday effect. The sensor (10) includes a light source (14) for emitting a beam of light which is transmitted through the magneto-optic material (28) with one or more layers which causes a rotation of the plane of polarization of the light beam in proportion to the current flowing in the conductor (12). The beam of light with the rotated plane of polarization is split by a beam splitter (38) into two components which are then processed to produce an outputs (62, 63) indicative of the AC and DC components of the current flowing in the conductor. The outputs (62, 63) produced are independent of system losses.

Abstract: The present invention provides a current detection device comprising a core skirt for accommodating therein a core, a core stopper for fixing the core and a magnetic-sensitive element mounted on a substrate, the substrate and the core skirt having engaging portions for locating the magnetic-sensitive element, respectively, provided thereon, and further provides a core for detection of a magnetic flux.

Abstract: An active current transformer has a primary conductor in which a current is to be measured and a secondary conductor in which a measuring current is generated in use. A feedback sensor provides an induced voltage and an amplifier receives a signal induced in the feedback sensor and generates the measuring current in the secondary conductor. The primary and secondary conductors are located in first and second magnetic circuits respectively, the first and second circuits having a common path over at least a part of their respective lengths. The feedback sensor is disposed on the common path of the first and second magnetic circuits so that, in use, the magnetic flux in the second path can be made substantially equal to that in the first path by operation of the amplifier in response to the voltage in the feedback sensor.

Abstract: A current sensor having an element made of amorphous magnetic metal is disclosed herein. The current sensor includes an element located near a conductor and made of amorphous magnetic metal whose magnetic property varies in accordance with the intensity of a magnetic field generated from a current flowing through the conductor, magnet applying a DC-bias magnetic field to the element, a coil exhibiting electrical property corresponding to the magnetic property of the element, and output device for outputting a signal corresponding to the electrical property of the coil. The coil has a specific positional relationship with the element, such that at least part of the magnetic flux generated by the coil passes through the element.

Abstract: A system for measuring parameters in an environment having a metallic body positioned in an electrolytic medium includes a current density sensing device positioned adjacent the metallic body in a non-invasive manner. The device is sufficiently sensitive to measure current density in the milliamp per square centimeter range. A housing is provided for enclosing at least a portion of the current density sensing device in an electrically and thermally non-conductive manner. A computer is used for processing the data from the current density sensing device and wiring is provided for electrically interconnecting the two. The current density sensing device, which can be used separately from the apparatus, includes a toroidal transformer and a square wave magnetically coupled oscillator which drives the transformer. A pair of multi-section low pass filters are provided for monitoring the transformer. A fixed gain differential instrumentation amplifier is utilized for processing an output of the transformer.

Abstract: A dual purpose probe for the simultaneous sampling of the voltage and curt at a test point. The device includes a capacitive probe for measuring voltage, and a small solenoid type inductor for measuring current when affixed so that it is at right angles to the wire being sampled. A small, double-sided circuit board has the inductor mounted thereon as well as a small metallic pick up plate which serves as one plate of a capacitor when the probe is affixed in the measuring position, while the conductor being sampled forms the other plate of the capacitor, and the insulation around the conductor serves as the capacitor dielectric.

Abstract: A sensor for sensing magnetic fields. A single mode optical fiber has a core which is wound into a helical shape. The fiber is formed with a former and a core, and the core is preferably attached to the inner surface of the former and wound into a helical shape tracing its inner periphery. The core is also offset from the central axis of the fiber former.

Abstract: A sensor (10) for sensing the magnitude of current flowing in a conductor (12) based upon the Faraday effect is disclosed. The invention utilizes a magneto-optic material having one or more layers (32) in which alignment with an optical fiber is not critical in achieving accurate current measurements. A magneto-optic material (28) in accordance with the invention includes one or more layers (32) each having a substrate having opposed surfaces coated with a material exhibiting the Faraday effect in which light from a light source is transmitted through the magneto-optic element without substantial internal reflection and is incident upon a surface area of the coating which is greater than the surface area of the beam of light.

Abstract: An electric current sensing device for measuring a primary current of relatively high intensity. The device includes a magnetic circuit that is coupled with a primary conductor and with a measuring coil that is connected to a current source through an associated control circuit. The magnetic circuit includes an air gap which accommodates a magnetic field detector that is electrically connected to an input of the control circuit for controlling a magnetic field compensating current that is supplied to the measuring coil. The device also includes a printed circuit that is arranged to both minimize electromagnetic interference between the measuring current circuit and the control circuit input, and improves heat dissipation of the printed circuit, thus optimizing the size ratio of the maximum primary current to the bulk of the device and improving performance of the same.

Abstract: A magnetic circuit is coupled with a primary conductor in which flows the current to be sensed. The magnetic circuit has an air gap with a magnetic field detector and is coupled with a measuring coil producing a magnetic flux for compensation the flux generated by the primary current. The necessary current in the measuring coil to achieve such flux compensation is a measure for the primary current. A yoke part of high magnetic permeability is arranged in the vicinity of the air gap inside the measuring coil so as to form a magnetic shunt between the two magnetic circuit portions forming the air gap.

Abstract: A current detecting device comprises a substrate, a magnetism sensing member made of ferromagnetic magnetoresistance element, an insulating member, and a conducting member, and these members are formed by a photolithography technique such that the magnetism sensing member is electrically isolated from the conducting member by the insulating member. When a current flows into the conducting member, the magnetism sensing member responds to a magnetic field generated by the current. At this time, the resistance of the magnetism sensing member changes due to a magnetoresistance effect in accordance with the intensity of the current. Therefore, the current can be measured by detecting the resistance change. In such a current detecting device, there is no reactance component thereby achieving high sensitivity when detecting the current.

Abstract: A combined current and voltage measuring sensor for measuring voltage and current on a primary conductor, the sensor including a cast resin body having therein a aluminum support, the support having an aluminum encasement mounted thereto. An open air coil is located in the encasement adjacent a grooved portion in the cast resin body for maintaining the primary conductor in the top of the cast resin body. The groove and the aluminum encasement cooperate to precisely located the primary conductor with respect to the open air coil. A keeper assembly mechanically maintains and locates the primary conductor in the groove and further provides an electrical connection from the primary conductor to the voltage measuring apparatus of the sensor.

Abstract: The invention relates to a system using Rogowski coils to measure the phase currents in a three-phase installation. Each coil (1, 2, 3) is connected firstly to a corresponding operational amplifier (10, 20, 30) connected as an integrator, and secondly to a corresponding inverter (100, 200, 300) whose output is connected to the inputs of the integrating amplifiers of the other two phases. With appropriately selected resistance values, mutual interference effects may be cancelled. The system is suitable for measuring phase currents in an installation housed in a cabinet or cubicle.

Abstract: A wide band large dynamic range current sensor operable to measure current leakage in an external conductor utilizing a magnetostatic spin wave delay line (MSW) device is described. The measurable changes in well known electromagnetic properties of ferrite films, as utilized in MSW devices when these films are exposed to external current induced magnetic fields, results in a current sensitive detection device. A method of current detection using this device is also described. Specific, low power microelectronic applications as well as, high power, local and remote current detecting embodiments are included.

Abstract: Supply circuit SC for a Hall sensor multiplication circuit HSC makes it possible to produce both circuits in monolithic technology on a common substrate and yet accomplish the polarity reversal of the output voltage U.sub.H of the multiplication circuit HSC with such accuracy that at said reversal the absolute value of the voltage U.sub.H is preserved with an accuracy of 0.01%.

Abstract: A system for monitoring an alternating current including: a current transducer (10) having first and second optical ports (12,14) and a component for causing optical radiation to travel between the optical ports (12,14) while interacting with the alternating current in a manner to cause the intensity of the optical radiation to vary as a function of variations in the amplitude of the current, with the polarity of the variation being dependent on the direction of travel of optical radiaiton in the transducer (10) between the optical ports (12,14); two optical cables (16,18) each optically coupled to a respective optical port; couplers (20,22) connected to the optical cables (16,18) for causing optical radiation to travel in both directions in the transducer (10) between the optical ports (12,14); and a circuit arrangement (24,26,28,30,38,40,52) for deriving a respective representation of the change in intensity experienced by the optical radiation traveling in each direction through the cables (16,18) and the

Abstract: A non-contact ammeter for measuring direct current in a conductor has a core capable of carrying a magnetic flux. The core surrounds the conductor so that the latter serves as a primary winding for the core. A second winding on the core is inductively coupled to the conductor. A current indicator is connected to the second winding. A control establishes the voltage on the second winding and flux changes in the core to avoid or limit saturation of the core. The control may be responsive to the flux condition of the core.

Abstract: A direct-coupled fluxgate current sensor which is driven to hard saturation to achieve a sudden change in magnetic properties of the sensor, has: (a) a first closed loop core of ferromagnetic material encased in a sleeve wound with a first toroidal drive winding, the winding for the first core extending around the circumference of the first core; (b) a second closed loop core of ferromagnetic material encased in a sleeve wound with a second toroidal drive winding independent of the first winding, the winding for the second core extending around the circumference of the second core; and, (c) a closed loop core casing which is adapted to cooperate with the first core and the second core, the closed loop core casing and the first and second core being wound as a unit with a toroidal sense winding independent of the first and second toroidal drive windings, the winding for the closed loop core casing extending around the circumference of the closed loop core casing.

Abstract: Circuit for detection of an asymmetry in the magnetization current, generated by a reference alternating voltage, in a magnetic modulator, in particular a magnetic modulator for zero-flux detection. This magnetic modulator comprises two virtually identical, wound magnet cores (T2, T3), each with a primary winding (W1) to be fed with a modulating current (i.sub.1) and a series circuit of an auxiliary winding (W3) and an impedance (Z2, Z3) across which a voltage proportional to the magnetization current arises during operation. The reference alternating voltage (U.sub.m) is fed to the respective series circuits (W3, Z2; W3, Z3) such that no resultant induction current is induced in the modulating current (i.sub.1). The voltages over the impedances (Z2, Z3) form input signals for two peak value detectors (PD1, PD2), the strength of the output signal of which represents the degree of asymmetry of magnetization current.

Abstract: A magnetic motion electrical generator includes an electrical winding defining a magnetically conductive zone having bases at each end, the winding including elements for the removing of an induced current therefrom. The generator further includes two pole magnets, each having a first and a second pole, each first pole in magnetic communication with one base of the magnetically conductive zone. The generator further includes a third pole magnet, the third pole magnet oriented intermediately of the first poles of the two pole electromagnets and in magnetic communication with the electromagnets, the third pole magnet having a magnetic axis substantially transverse to an axis of the magnetically conductive zone, the third magnet having a pole nearest to the conductive zone and in magnetic attractive relationship to the first poles of the two pole electromagnets, in which the first poles thereof are like poles.

Abstract: A current-measuring device in accordance with the invention comprises an annular magnetic circuit having separate first and second magnetic circuit portions (1, 2) with ends suitable for coming face-to-face to form a closed magnetic circuit, a housing (5) surrounding at least the first portion (1) of the magnetic circuit the first portion being slidably mounted within the housing, magnetic flux detection means (12) for detecting a magnetic flux in the magnetic circuit; the housing includes a bearing member against which the second portion of magnetic is firmly held when slided with the first portion from a position where the second portion does not face the bearing member to a position where the second portion faces the bearing member.

Abstract: There is disclosed a circuit arrangement including a load (7) and a current source (1) for supplying current to the load via a current path with a winding (3). A core of magnetizable material (2) is coupled inductively with the winding and a Hall effect transducer (4) detects magnetic flux in the core for use in producing an output indication dependant on the magnitude of the load current. For testing the correct functioning of circuit(s), the circuit arrangement is further provided with an additional winding (6) on the magnetizable core, through which a further current source supply a further current, in which the core is also inductively coupled so that the transducer also detects flux in the core due to the further current.

Abstract: A variable electrical current in a first winding on a magnetizable core produces a magnetomotive force in the core. A second core winding produces an opposing magnetomotive force digitally adjustable periodically by a third core winding, a pair of switches and a flip-flop coupled to a center tap for alternately closing such switches when triggered to opposite states. The flip-flop is triggered between opposite states when the third winding current reaches a particular magnitude. In each cycle, the time differences for producing the particular magnitudes and the opposite polarities are dependent upon the remanent core flux. Such time differences are counted digitally upwardly and downwardly for opposite polarities. The second winding current is adjusted digitally in each cycle in a direction to minimize such count. The magnitudes of successive adjustments may be compared periodically by adaptive tracking techniques to control the magnitudes of subsequent adjustments.

Abstract: A current detector for detecting the high frequency current flowing in a conductor includes a coil of high resistivity material wound around an non-ferromagnetic core. The coil is arranged in a substantially closed loop configuration around the conductor carrying the current to be measured. The ratio of the winding spacing to the cross sectional area of the coil is maintained constant over the length of the winding. A shield of high resistivity material surrounds the coil and is spaced from the coils and the shield has a gap oriented along an azimuth of the closed loop winding and directed orthogonal to the net current direction of the current induced in the coil. The ends of the coil are coupled to a high impedance voltage detector through high resistivity leads and a relatively low value resistor is coupled between the leads to reduce the quality factor.

Abstract: An AC electric energy meter is coupled to a source of AC electrical energy and to an AC load. A sensing circuit senses the amount of AC electric energy consumed by the AC electric load. An AC electric energy measuring circuit generates a pulse signal representative of the amount of AC electric energy consumed by the AC electric load. A switching circuit receives the pulse signal from the AC electrical energy measuring circuit and controls current flow from the AC electrical energy source to a stepper motor to drive an output shaft of the stepper motor in a unidirectional manner based on the pulse signal. A register is coupled to the output shaft of the stepper motor for registering the amount of electrical energy consumed by the AC electric load based on the amount of rotation of the output shaft of the stepper motor.

Abstract: The invention is concerned with a current-transformer arrangement for a static electricity meter, including a primary conductor carrying the alternating current to be measured and a secondary winding consisting of at least two coils connected in series, the output voltage from which is passed to an electronic integrating stage to produce a measuring signal independent of frequency.

Abstract: The longitudinal electro-optic effect is used with an external probe to make voltage measurements on electrical conductors.

Abstract: A leadless current-sensing device for sensing current flowing in a conductor when the device is positioned in the vicinity of the current-carrying conductor. The device has a probe having a set of two current sensors disposed at a preset radial angle alpha ".alpha." in respect to each other. The probe also has a second set of two current sensors also disposed at the same preset radial angle in respect to each other. The first and second sets of current sensors are disposed at a preset radial angle delta ".delta." in respect to each other. The first and second sets of current sensors are also disposed at a preset axial distance "z" in respect to each other. The device includes a voltage processing circuit for processing the four distinct voltage potentials induced in the four current sensors. The processing circuit compares to each other two voltage potentials from either set of current sensors to calculate the orientation angle that each current sensor makes with the conductor.

Abstract: A method of measuring the strength of a DC current and a device for implementing this method are provided, forming an NMR shunt for measuring high currents. A magnetic coil is placed in series in the circuit in which the current to be measured flows, the temperature of the magnet is stabilized and the magnetic field is measured in the center of the magnet using an NMR probe.

Abstract: In a voltage detector using an electro-optic material whose refractive index is changed by a voltage developing in a selected area of an object under test, an end portion of the electro-optic material has a corner-cube shape, whereby the detection of the voltage can be accurately achieved substantially being free from the influence of the input light tilt to the optical axis.

Abstract: The present invention is a current sensor employing a magneto resistive sensor having high fidelity of output. This current sensor includes a magnetic flux concentrator substantially encircling the electrical conductor having magnetic sensing, a magnetic device generating a magnetic field component along an axis offset from the principle axis, a magneto resistive device disposed in the magnetic sensing region, a constant current source supplying a predetermined constant current to said magneto resistive device, and a voltage sensing circuit connected to said magneto resistive device for measuring resistance by measuring a difference voltage induced by said constant current. This measured voltage corresponds to the current through the conductor. The magneto resistive device is formed as a Wheatstone bridge having a first and second pair of opposite terminals.

Abstract: Disclosed herein are individual sensor modules for mounting directly upon energized electrical power conductors and systems employing such modules, with principal emphasis upon the provision of both data transmitting and receiving means in each sensor module and at an associated ground station. The modules sense the instantaneous values of all parameters necessary to perform complete metering functions and, in one embodiment, are synchronized by a signal transmitted from the ground station and received by all modules so that the values are measured simultaneously on all conductors at a substation. The signals are transmitted by the modules in a time-synchronized manner and are in a condition for use directly by the ground station microprocessor. In another embodiment, data transmissions by a plurality of modules is synchronized to avoid data collisions by self-contained electronic apparatus within each module, requiring no synchronizing signal from the ground station.

Abstract: A circuit arrangement for finding a sum of electrical power outputs for use in a multi-phase electricity meter is disclosed. The circuit arrangement comprises a plurality of multiplier circuits arranged in sequence. The sequence of multiplier circuits has two poles which form the output poles of the circuit arrangement. Each multiplier circuit comprises a Hall element, an amplifier, and a polarity reversing switch.

Abstract: Current-measuring device including a non-contacting current sensor and an evaluating device connected downstream to the sensor for producing an output signal proportional to a current being measured, comprising a circuit arrangement for determining a zero drift of at least one of the evaluating device and the current sensor from symmetrical components of the current being measured and for correcting the drift.

Abstract: A current-measuring device in accordance with the invention comprises an annular magnetic circuit having separate first and second magnetic circuit portions (1, 2) with ends suitable for coming face-to-face to form a closed magnetic circuit, a housing (5) surrounding at least the first portion (1) of the magnetic circuit, magnetic flux detection apparatus (12) for detecting a magnetic flux in the magnetic circuit, and locking apparatus for locking the two magnetic circuit portions against each other; the device is characterized in that the locking apparatus comprise a bearing member (7) carried by the housing and pivot apparatus (7) enabling at least one of the magnetic circuit portions to pivot relative to the housing, in such a manner that during pivoting the second magnetic portion comes into contact with the bearing member and is firmly held against the first magnetic circuit portion thereby.

Abstract: A current sensor (10) comprising spaced pole pieces (62, 64) and a magnetic shunt (80) bridging the pole pieces within an insulating housing assembly (12) which also contains a magnetoresistive transducer (90) and electronic circuitry (16) for sensing magnetic field intensity between the pole pieces and relating that intensity as electric signals provided at terminals (26) at the exterior of the housing. The transducer senses magnetic field intensity along a principal axis (88). Permanent magnets (94, 96) or induction coils (276, 278) are provided to establish a biasing component of magnetic field intensity along an axis (98) substantially normal to the principal axis to improve sensor sensitivity, range of operation and immunity to current overload.

Abstract: A current ratio device for use in constructing a current transformer comprises a first magnetic core, a second magnetic core, a measuring winding electromagnetically coupled with the first core but not with the second core, and a compensating winding electromagnetically coupled with both cores. An externally powered amplifier has its input connected to receive the voltage waveform across the measuring winding. Its output provides a compensating current through the compensating winding equal to a magnetizing current required to magnetize the second core. The amplifier output also provides a measuring current through the measuring winding in the direction opposite that of the compensating current and equal to the compensating current multiplied by the ratio of turns in the compensating and measuring windings.

Abstract: The invention provides an ammeter specially suited for measuring the currents passing in high voltage, high power A.C. lines and, when required, storage of the resultant information, together with time of day and date over an extended period of time. The ammeter employs two C-shaped cores defining between two of the core arms a relatively large permanent gap that can pass the power line to facilitate mounting on the line using a live-line stick. One embodiment intended for mounting for an extended period of time also employs a clamp that can be manipulated using the stick to clamp it to the line and unclamp it, the clamp and core being related so that the power line passes through the center of the space between the cores. An embodiment intended for "spot" measurements has a locating member that performs the same function. A third device has the locating member in two parts that pivot to enable a large power conductor to pass through the slot in the locating member to the closed locating end thereof.

Abstract: A current probe is provided which comprises a handle and a ring of magnetisable material for positioning around an electrical conductor, the ring being split into two portions one being fixed relative to the handle and the other being slidable therewithin between a position in which the ring is closed and a position in which the ring is open. The line of split of the ring is at an angle from the line of sliding movement of the linearly slidable portion. Damping is provided to prevent the slidable portion of the ring from too rapidly moving from a position in which the ring is open to a position in which the ring is closed.

Abstract: A current sensor for use with a conductor with known cross-sectional characteristics is an electronic circuit having a monolithic Hall-effect element disposed substantially perpendicular to the conductor first major surface. A conductive loop substantially encircles the element and is oriented such that its flux is substantially orthogonal to the element surface. An amplifier sets current flow in the loop responsive to minimization of the differential Hall voltage across element. The loop current, at null, will be related to the conductor current by the ratio of the conductor flux path length to the loop flux path length.

Abstract: A low power consumption current transducer utilizes a saturable core reactor which includes a pair of opposed gate windings and a control winding. The control winding of the saturable reactor is arranged to receive the current to be measured. A square wave generator is connected to the gate windings via a transformer with the primary winding of the transformer connected across the square wave generator and the secondary connected in series with the gate windings of the reactor. A full wave rectifier is connected to the gate windings and a resistor is connected across the rectifier to provide a DC voltage thereacross representative of the current flow through the control winding. A DC power supply is provided to supply power to the square wave voltage source.

Abstract: The disclosed invention is primarily directed to sensor modules for mounting directly upon energized electrical power lines to monitor parameters associated with operation thereof, wherein the modules have a more compact lateral configuration than prior art modules designed for the same purpose. The modules include a first, cylindrical housing portion containing the sensors and other electronic data processing and transmitting elements, and a second housing portion, affixed to the exterior of the first portion and extending not more than about 150.degree. around the periphery thereof, and enclosing mechanical elements of the module mounting.

Abstract: The method is intended for use in a step-down high tension current measuring apparatus using the Faraday effect and including a Sagnac interferometer having an optical loop constituted by a fiber (47) surrounding the high tension conductor (11) conveying the alternating current to be measured and terminating at an integrated optical circuit (43) which delivers an output light beam to an electronic circuit with the optical power of the light beam having a component in its spectrum at a frequency which is a sinusoidal function of the phase difference generated by the Faraday effect, with the coefficient of proportionality being referred to as a scale factor. The method consists in periodically updating the scale factor used for interpreting measurements on the basis of D.C.

Abstract: A transducer for current measurements includes a flat conductor with at least two main current branches for the current to be measured and at least a cross-branch current bridge connecting two locations of differing potential of the two main current branches. A magnetic core is laid around one of the branch current paths. The flat conductor is formed such that it is provided in its cross-direction with a bending edge for redirecting current and each main current branch or part thereof at least approximately coincides with and is of an opposite current direction to a main current branch or part thereof of the other leg.

Abstract: A "hot-stick" mountable sensor module for attachment and removable from a live power transmission line. A tool is insertable into a mounted module to attach the module to the tool and permit removal of the module from the line.

Abstract: A magnetic flux concentrator comprising spaced pole pieces (4,6) and magnetic shunt (8) bridging the pole pieces within an insulating housing (2) which also contains a magnetoresistive transducer (24) and electronic circuitry (26) for sensing magnetic field intensity between the pole pieces and relating that intensity as electric signals provided at wiring terminals (28) at the exterior of the housing. The pole pieces have magnetic terminal portions adjacent openings in the housing for removable attachment thereto of selected ferrous strap configurations (42,50,52,60) determined by the cross-sectional shape of the electrical conductor (46) in which current flow is to be measured, the respective strap configuration and flux concentrator forming a magnetic loop around the conductor for picking up the magnetic flux induced by current flow in the conductor.

Abstract: An X-ray generator with current measuring device has an X-ray tube, a power supply unit for feeding high voltage to the X-ray tube, a high voltage cable for connecting the X-ray tube and power supply unit. The high voltage cable is comprised of a core conductor, an insulating layer surrounding the core conductor and a covered shield surrounding the insulating layer and the covered shield is disconnected near one end of the cable connected to the X-ray tube so as to be divided into a major shield portion adjacent to the power supply unit and a minor shield portion adjacent to the X-ray tube. An insulating member is provided for electrically insulating the major and minor shield portions, and a magnetic sensor sensitive to a magnetic field generated by a current flowing through the high voltage cable is positioned around the minor shield portion. The X-ray generator can measure the X-ray tube current accurately and readily under electrical insulation.

Abstract: A transformerless, self-contained, low cost, small size, light weight solid state electronic watthour meter is described which employs thin film ferromagnetic current sensors of the type which are magnetically coupled to power conductors whose current flow is to be sensed and metered and which provides electrical isolation between the power conductors and the sensing and metering circuitry. The meter is self-contained in that it draws its operating direct current supply potential required to operate the meter directly from the power conductors being metered and does not require a separate battery or transformer coupled direct current power source. The entire meter circuitry, including the thin film ferromagnetic current sensors which can be fabricated by thin film technology and the direct current power supply and the watthour meter circuitry, all are susceptible of fabrication on a single substrate using semiconductor integrated circuit fabrication techniques.

Abstract: A current sensing apparatus suitable for sensing the amount of current flowing in a power feeder cable without the necessity for any ohmic connection between the meter and the circuit being measured that does not require separation of the wires in a cable and in fact utilizes both current carrying wires simultaneously includes a magnetically permeable core suitable for concentrating the magnetic fields generated by the current flowing in the pair of wires and includes a single coil disposed upon the core. The core includes a pair of poles which are placed proximate to the feeder cable and the coil yields an induced output voltage proportionate to the current flowing in the feeder cable and may be held in position on the feeder cable with the aid of a resilient member which permits ready removal of the sensing apparatus.