A switching apparatus for carrying and disconnecting electric currents includes: a first mechanical contact arrangement; a second mechanical contact arrangement which is connected in series with the first mechanical contact arrangement; a semiconductor switch which is connected in parallel to the first mechanical contact arrangement; a switching electronics system for switching on and switching off the semiconductor switch; and a control circuit for ascertaining a voltage across the first mechanical contact arrangement as an ascertained voltage and generating an actuation signal for the switching electronics system, which actuation signal switches on the semiconductor switch, depending on the ascertained voltage. During a switching process, the switching apparatus closes the two mechanical contact arrangements with a time delay in relation to one another.

A circuit breaker comprises a solid-state switch, an air-gap electromagnetic switch, switch control circuitry, a zero-crossing detection circuit, and a current sensor. The solid-state and air-gap switches are connected in series in an electrical path between line input and load output terminals of the circuit breaker. The switch control circuitry controls the solid-state and air-gap switches. The zero-crossing detection circuit detects zero crossings of an AC power waveform on the electrical path. The current sensor senses current flow in the electrical path to detect a fault condition based on the sensed current flow. In response to a detected fault condition, the switch control circuitry generates control signals to place the solid-state switch into a switched-off state and place the air-gap switch into a switched-open state after the solid-state switch is placed into the switched-off state. The switch control circuitry utilizes zero-crossing detection signals output from the zero-crossing detection circuit to determine when to place the air-gap switch into the switched-open state.

A circuit breaker comprises a solid-state bidirectional switch, a switch control circuit, current and voltage sensors, and a processor. The solid-state bidirectional switch is connected between a line input terminal and a load output terminal of the circuit breaker, and configured to be placed in a switched-on state and a switched-off state. The switch control circuit control operation of the bidirectional switch. The current sensor is configured to sense a magnitude of current flowing in an electrical path between the line input and load output terminals and generate a current sense signal. The voltage sensor is configured to sense a magnitude of voltage on the electrical path and generate a voltage sense signal. The processor is configured to process the current and voltage sense signals to determine operational status information of the circuit breaker, a fault event, and power usage information of a load connected to the load output terminal.

A circuit breaker includes a circuit breaker housing, an air-gap switch disposed within the housing, and a first visual indicator configured to provide an indication of an open state and a closed state of the air-gap switch. The first visual indicator includes a first window that is formed as part of the circuit breaker housing, and first and second indicator elements disposed within the circuit breaker housing. The first indicator element is configured to move into position behind the first window as the air-gap switch is placed into the open state and thereby provide a visual indication of the open state of the air-gap switch. The second indicator element is configured to move into position behind the first window as the air-gap switch is placed into the closed state and thereby provide a visual indication of the closed state of the air-gap switch.

A circuit breaker includes an electromechanical switch, a current sensor, a voltage sensor, and a processor. The electromechanical switch is serially connected between a line input terminal and a load output terminal of the circuit breaker, and configured to be placed in a switched-closed state or a switched-open state. The current sensor is configured to sense a magnitude of current flowing in a path between the line input and load output terminals and generate a current sense signal. The voltage sensor is configured to sense a magnitude of voltage at a point on the path between the line input and load output terminals and generate a voltage sense signal. The processor is configured to receive and process the current sense signal and the voltage sense signal to determine operational status information of the circuit breaker and determine power usage information of a load connected to the load output terminal.

A circuit breaker includes a solid-state switch, a sense resistor, a current detection circuit, and a switch control circuit. The solid-state switch and sense resistor are connected in series in an electrical path between a line input terminal and a load output terminal of the circuit breaker. The current detection circuit is configured to (i) sample a sense voltage that is generated across the sense resistor in response to load current flowing through the sense resistor, (ii) detect an over-current fault condition based on the sampled sense voltage, and (iii) output a fault detection signal in response to detecting the over-current fault condition. The switch control circuit is configured to control the solid-state switch, wherein the switch control circuit is configured to switch-off the solid-state switch in response to the fault detection signal output from the current detection circuit.

The present disclosure proposes a switching device which, when supplying and interrupting power by combining a mechanical relay with a solid-state relay, suppresses the effects of chattering from the mechanical relay, and thus makes it possible to stably supply and interrupt power. Provided is the switching device including: a semiconductor relay configured to switch between supplying and interrupting power from a power supply; a mechanical relay configured to be connected in parallel to the semiconductor relay and connected at one end to a control terminal of the semiconductor relay; and a switch configured to switch between supplying and interrupting current to the semiconductor relay. The semiconductor relay turns on by high voltage being applied to the control terminal after current flows through a coil of the mechanical relay and a contact is switched, and the semiconductor relay turns off by low voltage being applied to the control terminal after current stops flowing through the coil of the mechanical relay and the contact is switched.

The present disclosure relates to a direct current arc extinguishing apparatus suitable for quickly extinguishing arc of mechanical contacts such as mechanical switches, where the mechanical switch requiring to extinguish arc is connected with a load in series. The direct current arc extinguishing apparatus includes a voltage detection switch and a capacitor, the voltage detection switch is connected with the capacitor; during the breaking of the mechanical switch, the capacitor forms a discharge loop by the voltage detection switch and the load, and is used for breaking arc extinguishing of the mechanical switch. The present disclosure is reasonable in design and has the advantages of low cost and high arc extinguishing speed.

A device, including: a sensor circuit that senses the state of contact impedance of a mechanical electrical switch; and a switch-off circuit that represents a sensed high impedance contact of the switch as a low or constant impedance, where the sensor circuit detects an open or closed condition of the switch by sensing a voltage across the switch passing a threshold value.

[Problem] A new and improved arc suppression device is provided that allows for reduction in power consumption in a semiconductor at a time of power shutoff by reducing power consumption of a current-limiting circuit that is used for suppression of an arc occurring at the time of power shutoff. [Solving means] Provided is an arc suppression device including one or more current-limiting circuits provided in parallel with a circuit breaker that switches between feeding and shutoff of power from a power supply. The current-limiting circuit shuts off a current from the power supply when the power from the power supply is fed to a load through a circuit breaker. The current from the power supply is shut off when a voltage generated by a potential difference between contacts of the circuit breaker becomes a predetermined voltage or higher in a case where feeding of the power from the power supply to the load is shut off by the circuit breaker. The potential difference is generated upon shutoff.