Disclosures of the present invention describe a switch device has a controlling and processing unit comprising a first zero point detector, a second zero point detector, an arc detector, and a microcontroller. According to zero crossing point of input voltage signal, zero crossing point of output voltage signal, relay's delay time, and arc-spark-induced signal, the microcontroller is capable of adaptively generating a relay controlling signal to control the relay, such that the relay achieves a short-circuit switching at the zero cross point of output voltage signal for making the output voltage signal be transmitted to at least one load device. Moreover, the microcontroller is also able to control the relay to finish a short-circuit switching at the zero cross point of input voltage signal, so as to stop the output voltage signal from being transmitted to the load device.

A monitoring device for switching systems including a contact assembly having at least a movable contact and a kinematic chain for actuating said movable contact and opening/closing the contact assembly. The monitoring device includes: an accelerometer adapted to be positioned on a moving part of the switching system and capable of determining acceleration data of the moving part; a control unit including: a first processing unit adapted to receive acceleration data measured by the accelerometer and calculate timing instants of predetermined events and motion parameters related to the switching system; a second processing unit adapted to receive the timing instants of predetermined events and the motion parameters and to use at least one timing instant and at least one motion parameter to calculate electro/mechanical parameters of the switching system.

A method for controlling a circuit breaker, the circuit breaker is connected in a three-phase system having an inductive load, and the method includes a method for controlling a circuit breaker, the circuit breaker being connected in a three-phase system having an inductive load, the method includes opening a first phase of the three-phase system before a zero crossing of a current in the first phase, opening the second and third phases of the three-phase system a quarter period after opening the first phase, closing the first and second phase at a peak voltage of a voltage between the first and second phases, and closing the third phase a quarter period after closing the first and second phases. A circuit breaker controller is also presented.

A method for operating an electrical switching device and an electrical switching device are disclosed. In order to ensure reliable operation of an electrical switching device having parallel switching paths allocated to a phase, which have lower switching capacity in comparison to conventional parallel switching paths, the zero current crossings in the phase are detected and at least one switching mechanism, operatively connected to the switching paths, is actuated so that all parallel switching paths allocated to the phase open within a window of time which is in the phase relative to the zero current crossings.

A PCB motor controller comprises relays mounted on a PCB and interconnected to power traces in or on the PCB to receive incoming three-phase power and to output three-phase power to a motor. Control power traces in or on the PCB connect the relays to control circuitry, also mounted on the PCB. A power supply is mounted on the PCB and connected to the control circuitry to provide power for its operation and for switching of the relays. The relays are switched in accordance with a point-on-wave (POW) switching scheme, allowing for the use or relays and the PCB, which may not otherwise be suitable for motor control applications.

An air conditioner includes a compressor to compress a refrigerant used in a refrigeration cycle, a converter to generate a DC voltage, an inverter to generate three-phase AC voltages from the DC voltage, a motor to produce a driving force for driving the compressor with a plurality of coils, the three-phase AC voltages being applied to the coils, a connection switching unit to switch connection states of the coils between a first connection state and a second connection state, and a controller to detect an abnormality of the connection switching unit.

Present invention relates to intelligent multi-way switch system having intelligent multi-way master switch, intelligent multi-way slave switch and load. In certain embodiments, the intelligent multi-way master switch includes a DC power supply, a live wire relay, and a local switch control unit, and intelligent multi-way slave switch includes a remote switch control unit. DC power supply provides low voltage DC power to live wire relay, local and remote switch control units of the intelligent multi-way switch system. When at least one of local or remote switch control units receives switch control instructions, local or remote switch control unit receiving switch control instructions generates a negative pulse at its switch control unit first terminal, and the negative pulse is transmitted to the live wire relay. Live wire relay detects the negative pulse generated at switch control unit first terminal and turns ON or OFF the electrical power to the load.

A method for controlling a circuit breaker, the circuit breaker is connected in a three-phase system having an inductive load, and the method includes a method for controlling a circuit breaker, the circuit breaker being connected in a three-phase system having an inductive load, the method includes opening a first phase of the three-phase system before a zero crossing of a current in the first phase, opening the second and third phases of the three-phase system a quarter period after opening the first phase, closing the first and second phase at a peak voltage of a voltage between the first and second phases, and closing the third phase a quarter period after closing the first and second phases. A circuit breaker controller is also presented.

A power switching control device includes a unit to measure a power-supply-side voltage of a circuit breaker, a unit to calculate a current that flows through a resistor after a switch is turned on and before a circuit breaking unit is turned on, and to calculate an interelectrode voltage of the circuit breaking unit after the switch is turned on and before the circuit breaking unit is turned on, a unit to determine a target closing time point for the circuit breaking unit so that a target turn-on phase for the circuit breaking unit becomes a phase that is set in accordance with the capacitor, and to output a control signal such that the circuit breaking unit is closed at the target closing time point.

In aspects, the present invention discloses a method of determining an electrical operating time of a circuit breaker (140) in a multiphase electrical system having a subsystem (160) connectable to a power source (110) through a circuit breaker (140) operated by a controller (130). The controller is connected to a current transformer (120, 150) for measuring current of the subsystem in a one phase. The method comprises monitoring the current of the subsystem in the one phase, determining a first rate of change from the monitored current in the one phase, detecting an instance of switching in an another phase based on the first rate of change, and determining an electrical operating time of the circuit breaker in the another phase based on the detected instance of switching and an instance at which a command for switching in the another phase was provided to the circuit breaker.