A step-by-step electric relay structure of a bistable type, comprising a mechanical part and an electric part, the mechanical part comprising push-button means to be operated by a user and the electric part comprising coil means, capacitor means, resistor means and diode means operatively interconnected to one another, the coil means comprising either two coils coupled in parallel to one another or a single coil polarized or biased with two polarities, thereby, as the push-button means are operated by the user to provide a switching or exchanging of at least a contact of the relay structure, either one of the two coils is shorted or the two polarities of the single coil are mutually reversed, thereby providing the electric relay structure with a logic SET function and a logic RESET function.

A contactor includes a coil through which current flows in an active state of the contactor; a controller configured to control the contactor; and a voltage converter, wherein, in the active state, the voltage converter is configured to converts an input voltage into a coil voltage which drops across the coil. The voltage converter can be electrically switched back into the active state from an inactive state using the controller. The contactor is configured to be switched into the active state from the inactive state by activating the voltage converter. The contactor is switched out of the active state into the inactive state by deactivating the voltage converter.

An abnormality detection circuit includes a first voltage detection circuit to which a voltage is applied from an AC power source when a first relay contact is closed and a second voltage detection circuit to which a voltage is applied from the AC power source when a second relay contact is closed. One end of the first voltage detection circuit is connected to the AC power source via the second wiring line while passing through no other switch. One end of the second voltage detection circuit is connected to the AC power source via the first wiring line while passing through no other switch. Abnormalities of the first and second relay contacts are detected by comparing the voltage applied to a comparative voltage detection circuit with each of the voltages applied to the first and second voltage detection circuits, respectively.

Disclosed is a DC adaptor for driving a magnetic contactor including at least: an AC input terminal; a capacitor connected to the AC input terminal; an electronic switch connected to the capacitor in parallel; a full-wave rectifier which converts an AC current into a DC current; a DC output connecting line which receives the DC current from the full-wave rectifier to transmit the DC current to the magnetic contactor; a sensing unit which measures a current value of a driving coil of the magnetic contactor; a controller which compares the measured current value with a reference value to output an on/off control signal of the electronic switch; a DC power source which generates a DC power using the DC current converted by the full-wave rectifier; and a housing which accommodates the above elements.

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.

Disclosed is a DC adaptor for driving a magnetic contactor including at least: an AC input terminal; a capacitor connected to the AC input terminal; an electronic switch connected to the capacitor in parallel; a full-wave rectifier which converts an AC current into a DC current; a DC output connecting line which receives the DC current from the full-wave rectifier to transmit the DC current to the magnetic contactor; a sensing unit which measures a current value of a driving coil of the magnetic contactor; a controller which compares the measured current value with a reference value to output an on/off control signal of the electronic switch; a DC power source which generates a DC power using the DC current converted by the full-wave rectifier; and a housing which accommodates the above elements.

A relay includes a first contact for receiving an input signal, a second contact for receiving a power signal, a rectifier coupled to the first and second contacts for converting the power signal into a direct-current power signal when the power signal is an alternating-current power signal, a voltage clamping circuit coupled to the rectifier for clamping a voltage of the input signal and the power signal, a Schmidt trigger coupled to the voltage clamping circuit for generating a trigger signal according to the input signal and the power signal, and a power outputting circuit coupled to the Schmidt trigger for generating an output voltage according to the trigger signal and a supply power.

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.

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.

A detection circuit module for use with a household appliance door to detect when the door is closed and/or locked, said 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 said diode being arranged electrically in parallel with the door locking switch.