An appliance with automatic sensing of printed circuit board (PCB) trace integrity and associated methods of sensing are provided. The appliance may include a controller operative to control operation of the appliance, a load in operative communication with the controller, and a PCB. The PCB may include a first trace supplying AC power to the load, a second trace supplying a return path for the AC power, a third trace supplying an alternate return path for the AC power, and current sensing circuitry. The current sensing circuitry may be configured to sense leakage current between the first trace and the third trace, with the leakage current being indicative of declining trace integrity of the PCB.

A current measurement device including current sensors positioned around current conductors in order to form a passage for the current conductors along an axis oriented in a first direction and a differential current sensor positioned around the set of current conductors in order to form a common passage for the current conductors along an axis oriented in a second direction. The current sensors and the differential current sensor are located in spaces that are separated by an interface plane. A method for manufacturing such a current measurement device, to a protection module and a differential circuit breaker including such a device.

A circuit interrupter including a line conductor, a neutral conductor, a power supply, a ground fault current transformer structured to sense a ground fault current from current flowing through the line and neutral conductors, a grounded neutral detection circuit including a filtering stage structured to high-pass filter the ground fault current, and a processor structured to receive an output of the grounded neutral detection circuit and to determine whether a grounded neutral is present based on the output of the grounded neutral detection circuit.

A circuit interrupting device includes a grounded neutral transformer core, a high frequency transformer core, and a differential transformer core nested within the grounded neutral transformer core and/or the high frequency transformer core. The grounded neutral transformer core and the high frequency transformer core are disposed in a stacked configuration with one another.

An arc fault detection arrangement for a DC electric bus, the DC electric bus having a plurality of electric lines adapted to electrically connect a source section and a load section of an electric apparatus, the arc fault detection arrangement including an arc fault detector adapted to receive and process detection signals indicative of AC currents flowing along the electric lines characterized in that it includes a current sensing device. The current sensing device includes: primary winding means including a plurality of first primary winding conductors adapted to be electrically connected in series with source portions and load portions of corresponding first line conductors of the electric lines; secondary winding means magnetically coupleable with the first primary winding means, the secondary winding means comprising at least a first secondary winding conductor electrically connected with the arc fault detector to provide the detection signals to the arc fault detector.

The circuit breaker according to the present invention comprises: a pair of contact mechanisms for switching a pair of circuits; a switching mechanism for driving the pair of contact mechanism to a circuit opening position or a circuit closing position; a trip bar rotatable to a first position for latching the switching mechanism or to a second position for releasing the switching mechanism; and an instant trip mechanism for pressing the trip bar to rotate to the second position, wherein the instant trip mechanism comprises a pair of armature assemblies and movable to a position for pressing the trip bar to rotate to the second position; and a pair of electromagnets provided to face the pair of armature assemblies and applies a magnetic attractive force to the pair of armature assemblies in response to the fault current on the circuit requiring an instant trip.

A circuit interrupter including a first electrical conductor, a second electrical conductor, separable contacts, an operating mechanism configured to open and close said separable contacts, a trip circuit configured to trip open said separable contacts, a ground fault detection circuit configured to sense a difference between a current through the first electrical conductor and a current through the second electrical conductor and to output an output signal based on said sensed difference, a power supply, a confirmation circuit structured to input a confirmation signal to the power supply, and a processor configured to receive said direct current power and said output signal. The processor is configured to determine whether a characteristic of said confirmation signal is present in said output signal and to control the trip circuit based on said determination.

A ground fault circuit interrupter device includes a switch module, a ground fault detection module, a self-testing module and a tripping module. The switch module is coupled between the input and output ends to control the electrical connection between the input and output. The ground fault detection module detects whether a leakage current signal exists at the output end. The self-testing module is coupled to the ground fault detection module and periodically generates a self-test pulse signal which simulates the leakage current signal. The tripping module is coupled to the ground fault detection module and the switch module, to control the movement of the switch module. The device includes at least two tripping drive components, which prevents the device from becoming ineffective when the tripping module malfunctions due to long time use or use under high temperatures. This greatly improves safety of the device.

A residual current device (RCD) comprises test circuitry which issues intermittent first test pulses each simulating a residual current fault for which a corresponding fault signal is generated. In the case of a fault in which a corresponding fault signal is not received in respect of a first pulse, the RCD attempts to force the load contacts open. The test circuitry further issues intermittent second test pulses at a frequency less than that of the first test pulses, each second test pulse simulating a residual current for which a corresponding fault signal is generated. The duration of each corresponding fault signal is greater than the response time of the load contacts to allow the load contacts to open. If the test circuitry detects that the load contacts do not open, the RCD attempts to force the load contacts open.

A ground fault circuit interrupter device includes a switch module having a reset switch, a control switch mechanically linked to the reset switch, a ground fault detection module, a self-testing module and a tripping module. The switch module controls the electrical connection between the input and output ends of the device. The ground fault detection module detects a leakage current signal at the output end. The self-testing module is coupled to the ground fault detection module and periodically generates a self-test pulse signal which simulates the leakage current signal. The tripping module is electrically coupled to the ground fault detection module and mechanically coupled to the switch module and the control switch, to control the movement of the switch module and the control switch. The control switch, which opens and closes at the same time as the reset switch, controls the power supply to the self-testing module.