An electric power supply system includes: a load; a first switch configured to connect a first electric power supply unit and the load to each other by a first route; a second switch configured to connect the first electric power supply unit and the load to each other by a second route; a third switch configured to connect a second electric power supply unit and the load to each other by a third route; a fourth switch configured to connect the second electric power supply unit and the load to each other by a fourth route; a first rectifying device provided in the second route and configured to carry out rectification from the first electric power supply unit toward the load; and a second rectifying device provided in the fourth route and configured to carry out rectification from the second electric power supply unit toward the load.

A circuit protective system. The system includes an output controlling enablement of a transistor and an input sensing an operational parameter associated with the transistor. The system also includes detection circuitry providing an event fault indicator if the operational parameter violates a condition. The system also includes protective circuitry disabling the transistor in response to the event fault indicator and subsequently selectively applying an enabling bias to the transistor; the enabling bias is selected from at least two different bias levels and in response to a number of event fault indications from the detection circuitry.

The present invention provides for an electronic functional device such as an isolator and arranged to offer configurable functionality for alteration of the function of the device, the device including wireless reception means for receiving wireless configuration data for the selective configuration of the device, and can also include wireless transmission means for the wireless transmission of data identifying its configured state.

A circuit breaker is disclosed for interrupting an electrical circuit when current limit values are exceeded. The circuit-breaker includes a current sensor for determining the electrical current flow and a control device. When current limit values are exceeded, the electrical circuit is interrupted. A first current limit value, when exceeded, results in an immediate interruption and a second current limit value, when exceeded, results in a time-delayed interruption, such that the second interruption time reduces as the current increases. Only one control element is included for setting a current limit value. The element defining the second current limit value is included for the time-delayed interruption of the electrical circuit. The other parameters are either set in a fixed manner and/or are related to the settable second current limit value.

The overload relay units within a motor control group have the timing function for their motor thermal memories under the control of a central controller in communication with the overload relays. Thus expensive timing components and control of timestamps can be removed from individual overload relays. Further reduction of individual overload relay components can be accomplished by removing the nonvolatile memory function from the individual overload relays and allowing the central controller to perform the nonvolatile memory functions for the overload relays. The motor thermal model function for the overload relays can remain in the overload relays or might be moved to the central controller if communication bandwidth permits.

A fail-safe operating method for a decentralized power generation plant DG includes determining a leakage capacitance of a generator of the DG before connecting the DG. The method also includes comparing the determined leakage capacitance with a predetermined first limit value, and connecting the DG to a grid only if the determined leakage capacitance is smaller than the predetermined first limit value. A decentralized power generation plant is configured to perform the method.

A dynamically coordinatable electrical distribution system includes a plurality of intelligently-controlled protection devices (PDs), a communication and control bus (comm/control) bus, and a central computer. The plurality of intelligently-controlled PDs is configured to protect a plurality of associated electrical loads from faults, developing faults, and other undesired electrical anomalies. Each of the PDs further has electrically adjustable time-current characteristics. The intelligently-controlled PDs are communicatively coupled to the comm/control bus and configured to report current data representative of real-time currents flowing through their respective loads to the central computer, via the comm/control bus. The central computer is configured to communicate with the plurality of PDs over the comm/control bus and dynamically coordinate the time-current characteristics of the plurality of PDs based on the current data it receives from the PDs.

An electronic motor starter has a main switch configured as a semiconductor, forming a semiconductor contactor and having at least one semiconductor switch for switching a phase of a supply of a motor winding, a first connection of each semiconductor switch being connected to a corresponding first main current contact of the motor starter; an auxiliary switch configured as a semiconductor switch and connected between at least one pair of auxiliary contacts of the motor starter; a transducer for measuring currents connected between a second connection of each main semiconductor switch and a corresponding second main power contact of the motor starter; and a controller foe the main and auxiliary switches being powered via motor starter control contacts, for being fed transducer measurement signals, and being configured to control the main and/or auxiliary switch according to the supply via the control contacts and/or according to the transducer measurement signals.

An electronic overload current breaker supports arc-fault and ground-fault (AFGF) detection along with built-in shunt calibration (BISC). The breaker may include a current sensing shunt and a control circuit electrically coupled to the current sensing shunt. This control circuit is configured to calibrate the current sensing shunt in response to application of a calibration current to the breaker. The control circuit can: (i) determine a magnitude of the calibration current applied to the breaker, (ii) map the magnitude of the calibration current to a first one of a plurality of current ratings for the breaker, and (iii) set the breaker to monitor overload conditions at the first one of the plurality of current ratings. The plurality of current ratings for the breaker can be less than the magnitude of the calibration current.

A ground fault circuit interrupter with a residual current device is suggested which comprises a tripping characteristic having a combined time-current curve that implements a minimum tripping time value of a first time-current curve and a second time-current curve for each current value.