A method for determining an optimized TCC operating curve for an electronic interrupting device that protects a distribution transformer in a power distribution network, where the TCC operating curve is some optimized predetermined percentage above a TCC curve for normal transformer operation. The method includes providing a TCC transformer curve that identifies an allowed transformer operation current once the transformer magnetics have been stabilized and the transformer is operating normally, and determining a TCC operating curve that is defined by points along the transformer curve plus a predetermined percentage above the transformer curve, where the operating curve identifies a response time for when the electronic interrupting device will open in response to a certain current flow.

An electronic device and method thereof of are provided to prevent burnout due to overcurrent. An electronic device includes a power amplifier configured to amplify a transmission signal; a battery configured to provide a bias voltage to the at least one power amplifier; and an overcurrent protection circuit configured to prevent overcurrent from flowing through the power amplifier. The overcurrent protection circuit includes a configurer configured to configure a reference current value, based on the power amplifier; a measurer configured to measure a bias current value due to the bias voltage; a comparator configured to compare the measured bias current value with the reference current value; and a controller configured to recognize overcurrent flowing through the power amplifier and control provision of the bias voltage, based on a result of the comparison.

An electrical circuit breaker system including an input terminal connecting an electrical current source and a plurality of output terminals for connecting electrical loads. Each output terminal includes an electrical switch and a current measuring unit. The circuit breaker system includes a current acquiring unit for acquiring current magnitudes measured at the output terminals and for determining a total current magnitude. A temperature acquiring unit acquires a temperature, and a computing unit is configured to determine a total current limit as a function of the acquired temperature. Further, a control unit is configured to select one of the plurality of output terminals based on a ranking of the output terminals and to interrupt the current supply at the selected output terminal by means of the corresponding electrical switch when the total current magnitude exceeds the determined total current limit.

Described are curve shapes that may be implemented in a transformer protector that provide enhanced fault protection. A transformer protector curve rating structure relates response curves to the transformer size and simplifies selection of response curves implemented within a transformer protector and associated transformer.

A voltage regulation apparatus and an overcurrent protection method are disclosed. The voltage regulation apparatus includes a current detection control circuit, a power stage circuit, a voltage input terminal, and a voltage output terminal. The power stage circuit includes at least one transistor. Because a current parameter indicates a load current of the at least one transistor, and a plurality of preset overcurrent protection thresholds are dynamic overcurrent protection thresholds obtained after being preset based on temperature information and the like, after obtaining the current parameter, the current detection control circuit compares the current parameter with the plurality of preset overcurrent protection thresholds, to output a control signal, to implement a limiting operation on the current parameter.

An overcurrent protection circuit includes an amplifier configured to amplify an inter-terminal voltage of a shunt resistor, an offset application circuit configured to allow the amplifier to provide an output with a predetermined offset voltage additionally applied thereto, a first comparator that compares an output voltage from the amplifier with a predetermined first reference voltage higher than the offset voltage to output a through-current sensing signal when the output voltage from the amplifier is higher than a first reference voltage, and an amplifier failure determination circuit that compares the output voltage from the amplifier with a predetermined second reference voltage that is higher than zero and lower than the offset voltage to output an amplification circuit failure determination signal corresponding to a result of the comparison.

A circuit protection apparatus includes separable contacts, an operating mechanism, an electronic trip unit storing a plurality of trip parameter combinations, wherein each of the trip parameter combinations specifies a certain value for each of a plurality of individual trip parameters, and a multi-position selector moveable among a plurality of predetermined positions and configured to enable selection of one of the predetermined positions. Each of the positions corresponds to a respective one of the trip parameter combinations, wherein the electronic trip unit is structured to, responsive to a chosen one of the plurality of predetermined positions being selected by the multi-position selector, cause the one of the trip parameter combinations corresponding to the chosen one of the plurality of predetermined positions to be used by the electronic trip unit to determine whether to cause the operating mechanism to trip open the separable contacts.

An overload control device for use with a floor machine having an electric motor is disclosed. The overload control device can include a power input and a power output connectable to the electric motor. The device can include a load detector, a current sensor operative to sense a current value supplied to the motor via the power output, and a cutoff relay interconnecting the power input and the power output. The cutoff relay being operative to supply power from the power input to the power output when activated, and interrupt power when deactivated. A controller receives a load present indication from the load detector and activates the cutoff relay if a load is present. The controller receives a current value from the current sensor, determines if the current value is greater than a threshold value, and deactivates the cutoff relay when the current value is greater than the threshold value.

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.

In a method for adapting an arc sensor (35) to a position in an electrical installation system, according to the invention a specifiable number of specifiable arcs are simulated and/or produced at least at a first position in the installation system, wherein after each simulated or produced arc, at least one current curve and/or voltage curve is recorded in a measured-value recording unit (2), wherein at least one characteristic of the recorded current curves and/or voltage curves is determined and stored, and the arc sensor (35) is trained for the electrical installation system.