A point-on-wave relay device includes a first contact relay and a second contact relay in series with the first contact relay. A first state of the first contact relay in conjunction with a first state of the second contact relay causes a point-on-wave open operation and second state of the first contact relay in conjunction with a second state of the second contact relay causes a point-on-wave close operation.

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.

Exemplary embodiments are disclosed that include multi-voltage contactors, controls, and related methods.

Provided is a capacitor discharge device that quickly and safely discharges a capacitor charged with energy inside a sub-module of an MMC converter, the device including: a capacitor storing a DC voltage inside a sub-module of an MMC converter; a power supply unit supplying operating power required in the submodule by using the voltage stored in the capacitor; a first resistor connected in parallel to the capacitor; a second resistor having a lower resistance value and a larger heat capacity than the first resistor so as to rapidly discharge the capacitor storing the voltage; a first switching contact connecting and disconnecting the capacitor and the second resistor; a switching unit operating switching of the first switching contact by the operating power; a second switching contact connecting and disconnecting the power supply unit and the switching unit; and a control unit operating switching of the second switching contact.

A detection circuit module for use with a household appliance door to detect when the door is closed and/or locked, the detection circuit module having a first and a second contact configured for electrical connection with the household appliance door so as to be operable with the household appliance door, the detection circuit module including: a door closing switch arranged electrically in series between the first connecting contact and an actuator; a door locking switch arranged electrically in series between the actuator member and the second connecting contact; and a diode arranged in series with the actuator and the second connecting contact and the diode being arranged electrically in parallel with the door locking switch.

A water and flame barrier button assembly is incorporated into an electrical enclosure such as a GFCI housing to provide water and flame resistant set and reset buttons. The buttons are contained within flexible sealing frames that allow one end of the buttons to extend through the top portion of the GFCI housing while the opposite end of the button is exposed within the base portion of the sealing frame. The base portion of the sealing frame attaches to the interior of the housing with the exposed button end positioned inward of the sealing frame base. The base of the sealing frame contacts the GFCI circuit board while providing a rebound force to return either the set or reset button exposed end from a position depressed and in contact with the circuit board to a position not in contact with the circuit board and returning inward of the sealing frame base.

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.

A power-saving circuit for a contactor includes a coil drive circuit, and further includes a rectification and filtering circuit, a PFC circuit, an auxiliary power supply circuit, and a square wave generation circuit. The square wave generation circuit outputs a first square wave signal to the PFC circuit via a first output end according to a set timing sequence, and outputs a second square wave signal and a third square wave signal to the coil drive circuit via a second output end, so as to respectively control duty cycles of a first switch tube in the PFC circuit and a second switch tube in the coil drive circuit. The auxiliary power supply circuit supplies electric energy to the square wave generation circuit during a holding stage of the contactor. The rectification and filtering circuit is used for rectifying an input AC into a pulsating DC, and filtering an input narrow-pulse current into a smooth current to be outputted to the PFC circuit after eliminating higher harmonic components other than a fundamental frequency component of 50 Hz. The PFC circuit receives rectified and filtered electric energy, enables an effective value of the input current to change along with an input voltage, and outputs the input current to the coil drive circuit and the auxiliary power supply circuit. The coil drive circuit is used for controlling the current of a contactor coil. Wherein during a pull-in stage of the contactor, the PFC circuit does not work and the power-saving circuit provides a large current to the contactor coil to pull in; during a transition stage, the PFC circuit starts to work and the power-saving circuit controls the current of the contactor coil to decrease gradually; and during a holding stage of the contactor, the PFC circuit keeps working and the power-saving circuit controls the current of the contactor coil to be kept as a small current required for holding.

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.

Exemplary embodiments are disclosed that include multi-voltage contactors, controls, and related methods.