An energy harvesting device (CTH) installed in an electrical distribution system (EDS) for powering ancillary electrical devices (AD) used in the distribution system. The device includes a first voltage regulator circuit (CC) configured to produce a voltage matched to a power curve of a current transformer (CT) to which the device is electrically coupled. The device also includes a second and separate voltage regulator circuit (SVR) which continuously operates to maximize the amount of electrical energy recovered from the current transformer.

A detector is provided that generates a leakage signal corresponding to a current imbalance between a line conductor and a neutral conductor for a load, and selectively injects a test signal into the neutral conductor. A frequency of the test signal substantially corresponds to a utility frequency. The detector measures a first value of the leakage signal, determines if the first value is less than first threshold value, and begins injection of the test signal into the neutral conductor in response to determining that the that first value is less than the first threshold value. In response to injecting the test signal, the detector measures a second value of the signal, determines if the second value is greater than a second threshold value, and disconnects the line conductor from the load in response to determining that the second value is greater than the second threshold value.

A detector is provided that generates a leakage signal corresponding to a current imbalance between a line conductor and a neutral conductor for a load, and selectively injects a test signal into the neutral conductor. A frequency of the test signal substantially corresponds to a utility frequency. The detector measures a first value of the leakage signal, determines if the first value is less than first threshold value, and begins injection of the test signal into the neutral conductor in response to determining that the that first value is less than the first threshold value. In response to injecting the test signal, the detector measures a second value of the signal, determines if the second value is greater than a second threshold value, and disconnects the line conductor from the load in response to determining that the second value is greater than the second threshold value.

An apparatus for identifying a fault in the windings of a distribution transformer, a transformer, and an associated method, said device comprising: a first Rogowski current sensor at a high-voltage incoming current terminal, and a second Rogowski current sensor in tandem at a low-voltage outgoing current terminal and at a low-voltage incoming current terminal; a first conductor of the low-voltage outgoing current terminal, passed through in one direction through the second sensor, and a second conductor of the low-voltage incoming current terminal, passed through in the opposite direction through the second sensor; the first and second sensors generate output signals indicating the primary current and the secondary current; both signals are integrated, generating output signals proportional to the primary current and the secondary current, obtaining a transformation ratio, which is compared with a threshold, and sending a fault signal if said threshold is exceeded.

A ground fault sensing circuit system includes a current transformer having a first winding and a second winding on opposite halves of the current transformer, outputting first and second signals, each winding coupled to a processor that determines information about respective currents in conductors monitored by the current transformer, based on a combination of the first and second signals. In another embodiment, the current transformer has a third winding wrapped continuously around both halves of the current transformer, overlapped with the first and second windings, the third winding outputting a third signal coupled to the processor, which determines information about respective currents in conductors monitored by the current transformer, based on a combination of the first, second, and third signals.

A ground fault sensing circuit system includes a current transformer having a first winding and a second winding on opposite halves of the current transformer, outputting first and second signals, each winding coupled to a processor that determines information about respective currents in conductors monitored by the current transformer, based on a combination of the first and second signals. In another embodiment, the current transformer has a third winding wrapped continuously around both halves of the current transformer, overlapped with the first and second windings, the third winding outputting a third signal coupled to the processor, which determines information about respective currents in conductors monitored by the current transformer, based on a combination of the first, second, and third signals.

A current transformer having a body having an upper half and a lower half hingedly connected to the upper half, a pair of ferrite cores located within one of the upper half and the lower half of the body, the pair of ferrite cores defining a gap formed between each ferrite core of the pair of ferrite cores, and a sensor located within the gap formed between each ferrite core of the pair of ferrite cores.

A current transformer having a body having an upper half and a lower half hingedly connected to the upper half, a pair of ferrite cores located within one of the upper half and the lower half of the body, the pair of ferrite cores defining a gap formed between each ferrite core of the pair of ferrite cores, and a sensor located within the gap formed between each ferrite core of the pair of ferrite cores.

The present disclosure provides a hinge, such as for housings for devices, such as a split-core current transformer. The housings can include hinges and housing parts to be rotatably coupled together at such hinges that can be injection molded. A hinge of a housing can include a first knuckle and a second knuckle, which can be integrally formed with or coupled to a first housing part and each are configured to receive an end of a hinge pin. One of the knuckles includes a knuckle slot to provide radial access for a cut-away portion of a hinge pin to pass through. At assembly of the first housing part to a second housing part, a first hinge pin end is to be disposed within an opening of the first knuckle and a second hinge pin end is to be disposed within the second knuckle after passage of the key portion through the knuckle slot of the second knuckle.

Modern X-ray generators are required to deliver a peak power between 30 kW and 120 kW. This requirement places demanding constraints on the design of the power inverters used to supply such X-ray generators, at the same time that there exist industry incentives to reduce the size of X-ray generators. An trend towards increased frequencies of switching operation in the power stage of modern X-ray generators makes it possible to use air-core inductors, rather than magnetic-core inductors. This application discusses an air-core inductor assembly having an integral current sensor. According to this application, a current sensor can be more accurately provided, which does not drift in position over time, and in a way which reduces the overall bill of materials.