An electric meter in a utility box is capable of detecting arcing conditions between meter blades and a meter socket in the utility box at a premises. The electric meter includes a current-transformer structure forming an enclosed space. An arc detection antenna can be placed in the enclosed space along with the current transformer. The current-transformer structure is placed on a baseplate of the electric meter near the blades connected to the meter socket. Leads of the arc detection antenna are electrically connected to an arc detection circuit configured to detect arcing conditions based on the signal received from the arc detection antenna. If it is determined that the arcing condition is present, the electric meter may be activated to interrupt the connection between the power source and the premises.

A method for non-contact current measurement is described. According to one exemplary embodiment, the method comprises the alternating magnetizing of a magnetic core to a maximum value in the positive and negative directions by controlling at least one secondary conductor which is magnetically coupled to the magnetic core; generating an oscillator signal which alternates between a first state and a second state, whereby the alternating magnetization processes are indicated; and determining a first measured value for an effective primary current which flows through at least one primary conductor which is magnetically coupled to the magnetic core, based on the times that the oscillator signal dwells in the first and the second state.

An electrical current transducer including a magnetic core and a magnetic field detector module, the magnetic core and magnetic field detector module each forming a single unit separably mountable around a primary conductor and to a circuit board, the magnetic core having a general U shape including an end branch and lateral branches extending the end branch to respective free ends, the magnetic field detector module being positioned between the lateral branches and extending across a whole width of a gap formed between the lateral branches. The magnetic field detector module includes at least one magnetic field sensing cell, a pair of magnetic concentrators arranged in mirror opposition forming a magnetic field gap therebetween in which the at least one sensing cell is positioned, and an insulating body supporting the magnetic concentrators and at least one sensing cell.

The invention relates to a method for cable condition monitoring of an electric cable. The method comprises inducing a test current in the electric cable, measuring a resulting current in a measurement point of the electric cable by measuring a magnetic nearfield of the electric cable, measuring a resulting voltage in the measurement point of the electric cable by measuring an electric nearfield of the cable, calculating an impedance of the electric cable based on the resulting current and the resulting voltage by a line resonance analysis system, and analysing the impedance by the line resonance analysis system establishing a condition of the electric cable. A coupler arrangement providing a non-galvanic connection to the cable is also disclosed.

Current transducer including a housing comprising a coil support, a magnetic core extending between a first end and a second end, and a coil comprising a plurality of windings formed around the coil support. The coil support comprises a core receiving channel within which the magnetic core is inserted, the coil support comprising a radially inner support portion and a radially outer support portion between which the core receiving channel is disposed. The radially inner support portion is slidably movable with respect to the radially outer support portion.

For contactless current measurement at a first primary conductor that is configured to conduct a first primary current having a first current strength, and at a second primary conductor that is configured to conduct a second primary current having a second current strength, a ring-shaped magnetic core that encircles the first primary conductor and the second primary conductor detects the total magnetic field in the magnetic core and generates from the total magnetic field detected in the magnetic core a signal corresponding to the superposition of the first current strength and the second current strength. The first or second magnetic field component or individually both are also detected, and from the detected first or second magnetic field component or from both, a signal corresponding to the first current strength or a signal corresponding to the second current strength or both are generated.

A current-measuring transducer device has a current transducer for measuring an electric current along a conduction path. The current transducer has a magnetic field-sensitive element for converting the magnetic field resulting from the current flow along the conduction path into at least one physical variable and a measuring device for measuring the physical variable. The current transducer device has a coil arrangement with at least one coil for simulating the magnetic field resulting from the current flow along the conduction path. There is also described a method for calibrating a corresponding current transducer and a computer program product for performing the calibration method.

Closed loop current transducer includes a fluxgate sensing unit, a compensation coil wound around the fluxgate sensing unit, and a transducer housing mounted around the compensation coil, the fluxgate sensing unit comprising a fluxgate housing, a ring-shaped fluxgate magnetic field detector mounted in the fluxgate housing, and a magnetic shield mounted in the fluxgate housing, the magnetic shield surrounding the fluxgate magnetic field detector. The fluxgate housing includes first and second central parts, each central part comprising a radially inner side wall, a radially outer side wall and a base wall joining the inner side wall to the outer side wall, a sensor housing portion being formed on one side of the base wall and receiving the fluxgate magnetic field detector therein.

A device and method for evaluating long-term operation of a transformer oil pump. An inlet of an oil pump is connected to an outlet of an oil tank through an oil pipe, and an outlet of the oil pump is connected to an inlet of the oil tank through an oil pipe. A pressure gauge is provided on the oil pipe to the inlet and the outlet of the oil pump, respectively. An ultra-high-frequency (UHF) sensor is provided on an inner wall of an oil pipe close to the oil pump. A pressure difference between the oil pipes to the inlet and to the outlet of the oil pump is monitored. A three-phase unbalanced current of a stator winding is monitored. The vibration of the oil pump is monitored. The rotor-to-stator rub is monitored. Based on the above inspection, a long-term health status of the oil pump is determined.

In a method for the determination of an electrical contact property in a contact region between a first contact element of a first plug device and a second complementary contact element of a second plug device, a property of a current path including the first contact element, the contact region, and from the second plug device only the second contact element is evaluated and an induction voltage is generated in the current path for a measurement in the current path to thereby enable to draw a conclusion about the electrical contact property.