Abstract: A device for measuring an electric quantity such as electric current flowing in an electric equipment unit, which device is in a case fitted on a mounting support, and having pass-through holes and terminals separated by insulating material, their number corresponding to the number of phases of the equipment unit, the holesto permit a conductor to pass therethrough, to be electrically connected to strips of terminals of the equipment unit the opposite end to electric contact strips of a load-side or line-side apparatus from the equipment unit and, for at least one terminal of the device, a magnetic core at least partially surrounding such terminal with an air-gap around which a secondary measuring coil is wound between two end portions of the magnetic core which define the air-gap, the coil(s) delivering a signal representative of the current flowing in the apparatus.

Abstract: A system and device for measuring voltage in a conductor having a voltage provides a first electrode surrounding and spaced from the conductor, and a second electrode surrounding and spaced from both the conductor and the first electrode such that there is no contact between the conductor and the electrodes or between the first and second electrodes. The first electrode is connected to a first input of a differential amplifier circuit and the second electrode is connected to the other input of the differential amplifier circuit. The output of the differential amplifier circuit provides a voltage signal in proportion to the voltage of the conductor, thus providing a non-contact means for measuring the voltage of a conductor without requiring a connection to ground while simultaneously providing a high level of rejection of external interference.

Abstract: Electrical currents are detected and analyzed across structural members in a structural joint, such as a fastener of a vehicle. In some aspects, printed circuit boards etched with Rogowski coil circuits are inserted proximate the structural members in the structural joint. The Rogowski coil circuits may detect an electrical current as it flows through the structural joint. An integrator may integrate a transient current to generate an output signal, such as when the vehicle is subjected to an electrical charge. The output signal may be transmitted to an Integrated Vehicle Health Management (IVHM) system for analysis. In various aspects, the IVHM system may enable recording and reporting of various aspects of the current to enable maintenance, inspection, or real time/near real time health assessment of the vehicle.

Abstract: Methods to identify a fluorescent lamp among multiple fluorescent lamps include: receiving input to a circuit including multiple fluorescent lamps operated by corresponding multiple control signals, each fluorescent lamp configured to output radio frequency (RF) signals in response to receiving a detection signal, the input to identify which first control signal is provided to a first fluorescent lamp; in response to receiving the input, providing a first discovery signal in place of each control signal provided to each fluorescent lamp, one fluorescent lamp at a time; determining that the first fluorescent lamp outputs RF signals; and identifying the control signal that was replaced with the detection signal that caused the first fluorescent lamp to output the RF signals.

Abstract: A device for measuring alternating voltage in a conductor under test using a first set of capacitive voltage sensors 32a-f mounted on an electrically insulating support member. The sensors are disposed on the support member at spaced intervals along a first notional circle and are connected in parallel between an inner signal conductor 33 and a zero voltage reference conductor 37. A second set of capacitive voltage sensors 34a-f are mounted on the support member at spaced intervals along a second notional circle and are connected in parallel between an outer signal conductor 35 and the reference conductor 37. The support member is configured to allow a conductor under test 38 to be introduced into the interior of the device so that the sensors surround the axis of the conductor. Each sensor has a signal electrode 48 connected to the signal conductor and a reference electrode 50 connected to the reference conductor and is orientated with the signal electrode facing the conductor under test.

Abstract: A conduit apparatus for an electrical enclosure that allows safe, convenient access for current measurement of circuits therein is provided. The conduit apparatus has one or more non-magnetic conduits extending therethrough. The conduits, in turn, each house a conductor. The conduits are accessible from outside the enclosure. By placing a hook-on type ammeter over the conduit, the current in the conductor may be measured. In one embodiment, the conduit apparatus is a component that mounts within a load center or other electrical enclosure. In another embodiment, the conduit apparatus is an integral portion of such an enclosure.

Abstract: A sensor linked with a power cable to produce a first signal in response to the presence of at least one of a sensed current and a sensed voltage within the power cable. The measuring circuit is electrically connected to the sensor to produce a second signal in response to the first signal representative of the magnitude of at least one of the sensed current and the sensed voltage within the power cable. The measuring circuit also produces a third signal in response to the first signal representative of a sensed frequency of at least one of the sensed current and the sensed voltage within the power cable. The measuring circuit includes a model of a set of predetermined relationships between a plurality of reference frequencies and a reference amplitude for each of the reference frequencies for at least one of the sensed voltage and the sensed current of the power cable.

Abstract: A rotary shutter for controlling an optical path and including a rotating disk having an opening. A sensor monitor is representative of disk rotation, while a blocking element is selectively positioned within and without the optical path dependent upon the angular position of the disk and the desire to expose the light sensitive medium.

Abstract: A power measuring system includes a transformer that produces a voltage signal in response to the presence of a changing current within a power cable. An input circuit is electrically connected to the transformer for receiving the voltage signal, and produces an analog current signal representative of the changing current within the power cable, in response to receiving the voltage signal. A transmission line has a first end electrically interconnected with the input circuit so as to receive the analog current signal and has a second end electrically interconnected with an output circuit located at a location remote from the first end. The output circuit receives the analog current signal and produces a resultant signal in response to receiving the analog current signal. The resultant signal may be used to provide a meter display. A housing for a sensing transformer having a split toroidal core is disclosed.

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: 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: 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 clamp-on ammeter for measuring current flows in a conductor is described. The ammeter is of a type comprising a magnetic core which can be located about a conductor and an indicator which responds to the magnetic flux consequently generated in the magnetic core to produce a signal indicative of the magnitude of the conductor current. Means are provided for restoring the magnetic core to a predetermined magnetic state for each measurement. The resetting means include a coil wound about the core and a coil energizing circuit which can be activated to produce in the core a residual magnetic flux substantially identical to that produced in the core when unmagnetized by a DC conductor current of predetermined magnitude, which represents the maximum value of any DC current which can be measured by the ammeter.