Abstract: A ground fault circuit interrupter (GFCI) device with self-test function includes: hot and neutral conducting circuits; an fault detection circuit responsive to a fault in the hot and neutral conducting circuits to generate a fault detection signal; a signal driving circuit responsive to the fault detection signal to generate a drive signal; a disconnecting mechanism for disconnecting electrical connections in the hot and the neutral conducting circuits when the drive signal exceeds a predetermined level; a self-test circuit for generating a self-test signal according to a predetermined time period and when an alternating current of the power source passes zero points, generating an evaluation result based on the self-test signal and a feedback signal of a fault detection signal corresponding to the self-test signal, and generating error signals if the evaluation result indicates a circuit error; and a device-state indicator circuit for generating alarms based on the error signals.

Abstract: A ground fault circuit interrupter (GFCI) device with self-test function includes: hot and neutral conducting circuits; an fault detection circuit responsive to a fault in the hot and neutral conducting circuits to generate a fault detection signal; a signal driving circuit responsive to the fault detection signal to generate a drive signal; a disconnecting mechanism for disconnecting electrical connections in the hot and the neutral conducting circuits when the drive signal exceeds a predetermined level; a self-test circuit for generating a self-test signal according to a predetermined time period and when an alternating current of the power source passes zero points, generating an evaluation result based on the self-test signal and a feedback signal of a fault detection signal corresponding to the self-test signal, and generating error signals if the evaluation result indicates a circuit error; and a device-state indicator circuit for generating alarms based on the error signals.

Abstract: A ground-fault circuit interrupter (GFCI) power receptacle with reverse wiring protection. The GFCI power receptacle has a circuit board assembled in a housing; a pair of resilient movable conducting arms attached to the circuit board, each having a movable contacts at its free end, a pair of stationary conducting arms each having a stationary contact at one end, and a pair of output face terminals each having a contact. The movable contacts can contact the stationary contacts and the output face terminal contacts to establish electrical connection between the input and output terminals of the power receptacle. The power receptacle has a simple structure where one movable contact can connect or disconnect the load in various working conditions, which can be used in various types of power receptacles.

Abstract: A power plug includes a base, an upper cover attached to the base, a base-side cover adjacent the base and removeably attached to the upper cover, an output cord, a leakage current detection and protection circuit for detecting a leakage current in the output cord, and an electrical connection mechanism for electrically connecting and disconnecting an input side and an output of the power plug. The leakage current detection and protection circuit and the electrical connection mechanism are attached to the base and disposed substantially within a space enclosed by the base and the upper cover. A plurality of connecting ends of the circuit extend from the space enclosed by the base and the upper cover into a space enclosed by the base-side cover and the upper cover. Wires of the output cord are connected to the connecting ends, respectively.

Abstract: A disconnect mechanism for a power receptacle, which includes a disconnect block, a locking member slidably coupled to the disconnect block, and an electromagnetic device moveably coupled to the locking member. The disconnect block includes two side arms extending outwards. A pressing plate is disposed above the disconnect block, and a disconnect spring is disposed above the pressing plate. The moveable contact arms of the main switch of the receptacle are disposed between the pressing plate and the disconnect block, and the pressing plate pushes the moveable contact arms when the main switch is being opened when a current leakage is detected. The receptacle also includes an auxiliary switch disposed because the disconnect block and the circuit board.

Abstract: A safety shutter for a power receptacle includes two identical sliding blocks engaged with each other and two biasing members. Each sliding block has a base and a platform extending from the base with a slanted surface. The slanted surfaces are disposed below the holes of the receptacle. The biasing members are helical torsion springs disposed at the end of the sliding blocks. The platform of each sliding block is disposed above the base of the other sliding block so the shutter normally blocks access to the conductors inside the receptacle. When two prongs of a plug are inserted into both holes, the prongs push on both slanted surfaces, causing the shutter to open. When a foreign object is inserted into only one hole, only one sliding block is moved by the foreign object and the base of the other sliding block still blocks access to the conductors.

Abstract: A GFCI device with circuit condition detection function includes a leakage current detection circuit, a disconnect mechanism, a reset mechanism, a circuit condition detection and control circuit, and a selection switch. The disconnect mechanism includes a first SCR controlled by the leakage current detection circuit. The circuit condition detection and control circuit includes a first control circuit and a second control circuit. When the first control circuit is connected to an anode of the first SCR by the selection switch, it provides an intermittent simulated leakage current to the leakage current detection circuit, and the leakage current detection circuit provides a trigger signal for a control gate of the first SCR, so that the first control circuit generates an intermittent simulated leakage current. When the leakage current detection circuit is not operational to generate the trigger signal, the first control circuit generates a control signal to disable the GFCI device.

Abstract: A power cord with leakage current detection function includes three copper wires for carrying power and at least one leakage current detection conductor for detecting leakage current. Each copper wire is surrounded by an insulating layer. At least two of the insulating layers are each surrounded by a metal conductive layer. The leakage current detection conductor is adjacent and in electrical contact with the two metal conductive layers. An outer insulating layer encloses the three wires and the leakage current detection conductor. The metal conductive layers are made of a thin copper foil, tin foil, aluminum foil, or conductive rubber. The leakage current detection conductor may be formed of copper wires or aluminum wires. Such a power cord provides low cost and reliability, and can quickly and accurately detect leakage current in the cord.

Abstract: An improved ground-fault circuit interrupter (GFCI) receptacle with reverse wiring protection. If the power lines are incorrectly connected to the load end of the receptacle during installation, power output to both the input end of the receptacle and the insertion outlets on the faceplate is prevented. The GFCI receptacle includes two stationary terminals on two first output conductors electrically connected to the insertion outlet, two stationary terminals on two second output conductors adapted for electrically connecting to the load, and four moveable terminal on two moveable connector arm adapted for electrically connecting to the power lines. The four moveable terminals corresponds in position to the four stationary terminals, respectively, and operate to electrical connect or disconnect the power lines to and from the load and the insertion outlet in a manner controlled by a disconnecting mechanism assembly and a reverse wiring protection mechanism.

Abstract: An improved ground-fault circuit interrupter (GFCI) device has a moveable lock plate controlled by a relay to block a hole under the reset guiding member to prevent reset of the device. The moveable lock plate blocks the hole and prevents reset when the relay is not energized, and expose the hole to allow reset when the relay is energized. The relay is powered by a power supply circuit which is connected in series with a solenoid across the input side of the GFCI. The solenoid is controlled by a control circuit, and causes a disconnecting assembly to disconnect the input and output sides of the GFCI when a leakage current is detected. If the solenoid malfunctions, or if the GFCI device is reversely wired, the relay is not energized and the device cannot be reset.

Abstract: A power cord with leakage current detection function includes three copper wires for carrying power and at least one leakage current detection conductor for detecting leakage current. Each copper wire is surrounded by an insulating layer. At least two of the insulating layers are each surrounded by a metal conductive layer. The leakage current detection conductor is adjacent and in electrical contact with the two metal conductive layers. An outer insulating layer encloses the three wires and the leakage current detection conductor. The metal conductive layers are made of a thin copper foil, tin foil, aluminum foil, or conductive rubber. The leakage current detection conductor may be formed of copper wires or aluminum wires. Such a power cord provides low cost and reliability, and can quickly and accurately detect leakage current in the cord.

Abstract: A power plug includes a base, an upper cover attached to the base, a base-side cover adjacent the base and removably attached to the upper cover, an output cord, a leakage current detection and protection circuit for detecting a leakage current in the output cord, and an electrical connection mechanism for electrically connecting and disconnecting an input side and an output of the power plug. The leakage current detection and protection circuit and the electrical connection mechanism are attached to the base and disposed substantially within a space enclosed by the base and the upper cover. A plurality of connecting ends of the circuit extend from the space enclosed by the base and the upper cover into a space enclosed by the base-side cover and the upper cover. Wires of the output cord are connected to the connecting ends, respectively.

Abstract: A leakage current detection and protection circuit in a power plug includes an SCR (silicon-controller rectifier), diodes, capacitor, resistors, and a solenoid with a plunger. The control gate of the SCR is connected via a resistor to a metal sheath L of the cord. The solenoid SOL, the SCR and a diode are connected in series and connected across the hot and neutral lines of the power line (either line or load side), forming an SCR conducting path. When wire for the hot, neutral or ground lines in the cord is exposed due to damage or aging, the sheath around the wires becomes live, forming a conducting circuit from the sheath, resistors and diodes to the hot or neutral lines. The voltage on the resistor causes the SCR to conduct, which energizes the solenoid to open a switch between the line side and load sides of the plug.