A fault clearing circuitry provided for connecting to at least one electrical line transmitting power includes: an electrical energy storage; at least one controllable switch connectable between the electrical energy storage and at least one electric line; and a control circuit for monitoring the at least one electric line for a fault and to close the at least one controllable switch if a fault is detected. The electrical energy storage stores an amount of electrical energy dimensioned to be sufficient for releasing one or more circuit breakers or clearing one or more fuses in the at least one electrical line in order to clear the fault. The control circuit closes the at least one controllable switch if a fault is detected such that a discharging of the electrical energy stored in the electrical energy storage is incurred injecting a current pulse in the at least one electrical line.

A circuit and a method for shutdown of automatic ignition controls upon valve relay failures. One or more embodiments describe a method including controlling a power supply to a valve by a valve drive circuit, the valve drive circuit comprising a first relay coil and a second relay coil. The method also includes controlling the valve drive circuit by checking the first relay coil and the second relay coil and issue a drive signal to the first relay coil and the second relay coil. The method further includes protecting from accidental supply of power by a protection switch based on the drive signal issued by the controller.

A system for detecting overloads of a motor comprises a motor configured to receive power via a lead line, a first sensing device configured to sense a temperature of a motor, and a second sensing device electrically coupled to the motor and configured to detect a target current of the motor and trigger a contact of the lead line associated with second sensing device when the target current equals or exceeds a trip value.

A differential protection device is designed for an electric disconnecting apparatus, the disconnecting apparatus comprising at least one fixed contact suitable for being connected to a corresponding electrical conductor, at least one movable contact, between a closed position, the movable contact being electrically connected to the corresponding fixed contact in the closed position and electrically isolated from the corresponding fixed contact in an open position, and an actuator for activating opening of the movable contacts when a differential fault is detected. The differential protection device comprises a controller for controlling the actuator. The differential protection device further comprises measuring circuitry for measuring an electrical variable associated with the controller and inhibiting circuitry for inhibiting the controller when the measured electrical variable satisfies a predetermined criterion.

An air conditioner and a compressor protection circuit thereof are provided. When overcurrent occurs in a phase current of a compressor, an overcurrent level signal is output by a voltage comparison module, and is latched and output to an intelligent power module by a signal latching module, and the intelligent power module shuts off the output of the phase current according to the overcurrent level signal, so as to achieve the overcurrent protection of the compressor; and subsequently, a conventional level signal is output to the signal latching module by the voltage comparison module, the signal latching module keeps outputting the overcurrent level signal, and outputs the conventional level signal until a latching cancel signal output by a signal processing circuit is received, so that the intelligent power module starts the output of the phase current, thereby enabling the compressor to normally operate.

There is provided a driver circuit for an electric device of an intrinsically safe circuit. The driver circuit includes a coupling capacitor configured to be open to AC voltage signals and to decouple DC voltage signals, the coupling capacitor includes first and second terminals, and is electrically connected to a first output line of the driver circuit by the first terminal; a first circuit configured to detect an output current of the coupling capacitor, which flows from the first terminal to the first output line; a switchable element electrically connected to the second terminal; means for controlling switching behaviour of the element, configured to switch the element from an electrically blocking state to an electrically conductive state when the output current at the first terminal exceeds a predefined threshold, so that the element in the conductive state causes discharge of of the coupling capacitor via the second terminal.

Process for regulating a compressor with motor for a refrigerating system, where the temperature of the cooling site is regulated through an on-off motor mode if the temperature in the compressor exceeds an upper temperature threshold. In addition, the temperature of the cooling site is regulated through a continuous on mode of the motor as soon as the motor has cooled to a lower temperature threshold. The controller converts a variable corresponding to the cooling requirement of the cooling site into a switch signal for a valve, which results in clocked opening and closing of the valve, or uses a frequency converter, which controls the cooling liquid flow through the compressor by regulating the voltage and the frequency of the motor in that the frequency converter converts a variable corresponding to the cooling requirement of a cooling site into a voltage and a frequency for the motor.

Circuit protection devices, power distribution systems, and methods of monitoring circuit protection devices are described. In one example, a method of monitoring a circuit protection device in a zone selective interlocking (ZSI) system includes monitoring a variable associated with operation of the circuit protection device, determining, based at least in part on the monitored variable, when a likelihood of a malfunction of the circuit protection device exceeds a predetermined threshold, and preventing the circuit protection device from outputting a ZSI blocking signal when the likelihood of the malfunction of the circuit protection device exceeds the threshold.

A current detection apparatus includes a voltage detector, a candidate voltage generator, a temperature detector and a correction voltage selector. The voltage detector includes an output terminal for outputting a detected voltage according to a load current. The candidate voltage generator includes correction resistors connected in series and connecting the output terminal and a ground. The candidate voltage generator generates candidate voltages at respective sections across the corresponding correction resistors. The temperature detector detects a temperature of a semiconductor switch. The correction voltage selector selects one of the candidate voltages as a corrected voltage. The one of the candidate voltages is weighted with corresponding one of the corrected magnification scales corresponding to an on-resistance of the semiconductor switch at the measured temperature. The corrected voltage indicates a corrected current value with correction of the load current according to the measured temperature.

A power supply for supplying power to a chipset includes a first voltage regulating circuit, which is configured to convert an applied power supply signal into a group of first supply voltages, and a second voltage regulating circuit, which is configured to convert the applied power supply signal into a group of second supply voltages. A control circuit is provided, which is configured to selectively enable the second voltage regulating circuit to generate the group of second supply voltages. An output discharge circuit is provided, which is configured to discharge an output stage of the first voltage regulating circuit in response to a transition of the first voltage regulating circuit from an active state to an inactive state. This transition of the first voltage regulating circuit from an active state to an inactive state can occur in response to a change in magnitude of the power supply signal.