Embodiments of the invention include an under-voltage lockout (UVLO) circuit with automatic UVLO threshold configuration. In an embodiment, the UVLO circuit includes an over-voltage protection circuit that receives power from a power source, a peak detector that detects a peak voltage output for the external power source, a voltage threshold generator that sets a UVLO threshold based on the peak voltage output, and a comparator that compares an instantaneous voltage with the UVLO threshold and configures an operating mode of a device based on the comparison.

In accordance with an embodiment, a circuit includes: a supply pin and an output pin for connecting a load, and a configuration pin; a semiconductor switch connected between the supply pin and the output pin and configured to establish or to block a current path between the supply pin and the output pin depending on a control signal; and a control circuit configured to generate the control signal for the semiconductor switch taking account of a first parameter, and set the first parameter depending on a component parameter of an external component connected to the configuration pin. The first parameter is set to a first standard value when the component parameter is less than a first threshold value, and the first parameter is set to a second standard value when the component parameter is greater than a second threshold value.

A field programmable circuit breaker receives a measurement of a displacement of a terminal spring element, from a detector associated with the terminal spring element, when a field wire is inserted into the terminal spring element. The terminal spring element provides a wire clamp force in a terminal configured to receive the inserted field wire. A trip current value is determined based on the wire size and a time interval is measured during which the current in the field wire is continuously greater than the trip current value. A trip curve is accessed corresponding to the trip current value to determine whether the measured time interval exceeds a maximum interval indicated by the trip curve. A tripping signal provided to a current monitoring unit interrupts the current when the measured interval exceeds the maximum interval for the measured current to be continuously greater than the trip current value.

The present invention relates to current measurement apparatus. The current measurement apparatus comprises first and second measurement devices with each of the first and second measurement devices being operative to measure current in a respective one of a live conductor and a neutral conductor substantially simultaneously. The current measurement apparatus is operative to make plural different determinations in dependence on the substantially simultaneous current measurements.

There is described a method of determining power transmission line parameters using non-synchronous measurements acquired from different locations along a power transmission line. The method comprises (a) acquiring first measurement data comprising corresponding pairs of voltage and current measurement values measured at a first location along the power transmission line at predetermined points in time relative to a first time reference, (b) acquiring second measurement data comprising corresponding pairs of voltage and current measurement values measured at a second location along the power transmission line at predetermined points in time relative to a second time reference, (c) calculating initial values of the power transmission line parameters and an initial value of the difference between the first time reference and the second time reference based on the first measurement data and the second measurement data, and (d) calculating resulting values of the power transmission line parameters and a resulting value of the difference between the first time reference and the second time reference by utilizing a least squares algorithm and the initial values of the power transmission line parameters, the initial value of the difference between the first time reference and the second time reference, the first measurement data, and the second measurement data. Furthermore, a data acquisition device and a system for determining power transmission line parameters as well as a computer program and a data carrier are described.

A directional overcurrent relay using a superconducting fault current limiter voltage as a relay element includes: a current measuring circuit measuring a current of a line connected from a system power source to a load, a voltage measuring circuit measuring a voltage at both ends of a superconducting fault current limiter connected to the line, and a correcting circuit correcting a tripping time T.sub.trip by using a fault current I.sub.f that is the current of the line and a superconducting fault current limiter voltage V.sub.SFCL that is the voltage at both ends of the superconducting fault current limiter and the tripping time T.sub.trip is maintained consistently regardless of whether the superconducting fault current limiter operates or not.

One example includes a power relay system. The system includes a circuit breaker configured, when triggered, to provide an open circuit in a power line configured to conduct a current between a power grid point-of-interconnect (POI) and a power generator system. The system also includes a power controller configured to monitor the current and to generate a dynamic current threshold based on the current, the power controller being further configured to compare the current with the dynamic current threshold and to trigger the circuit breaker based on a difference of the current relative to the dynamic current threshold to set an arc flash incident energy level of the power generator system to less than or equal to a predetermined safety level.

The disclosure relates to an energy supply apparatus for the overcurrent-protected electric power supply to an electric consumer, including a power supply device configured to provide an electric current for the electric consumer, and a controllable power protection element configured to disable a supply of electric current to the electric consumer when the electric current reaches a first current limit value, wherein the controllable power protection element comprises an adjustable second current limit value set by the power supply device, wherein the power supply device receives an increased power requirement of the electric consumer within a time interval and to control the controllable power protection element for a duration of the time interval to set the second current limit value, and wherein the controllable power protection element disables the supply of the electric current to the electric consumer upon reaching the second current limit value by the electric current.

A method and a device for locating faults along an energy supply chain for DC current systems. To provide a reliable fault location for DC current systems, at least one reference short circuit is generated at a known reference fault location of the energy supply chain and at least one physical property of the energy supply chain is determined during the reference short circuit. At least one physical property of the energy supply chain during the operational short circuit is determined, and a fault location of the operational short circuit is determined, taking into account at least the determined physical properties during the reference short circuit and the operational short circuit and the reference fault location.

A switching device includes two connection lands, a measurement device for measuring a first quantity of a current flowing between the two lands, a power supply system and a trigger module, the latter including a first driver module for detecting an electrical fault according to first values stored in a first memory and controlling a switching member; a communication module for receiving and storing second values in a second, non-volatile memory; and a second driver module for replacing the first values with the second values in the first memory. The first driver module compares a second quantity of the first supply current with a threshold and controls the supply of power to the second driver module if the second value is higher than or equal to the threshold.