A circuit breaker includes an electromechanical switch, a current sensor, a voltage sensor, and a processor. The electromechanical switch is serially connected between a line input terminal and a load output terminal of the circuit breaker, and configured to be placed in a switched-closed state or a switched-open state. The current sensor is configured to sense a magnitude of current flowing in a path between the line input and load output terminals and generate a current sense signal. The voltage sensor is configured to sense a magnitude of voltage at a point on the path between the line input and load output terminals and generate a voltage sense signal. The processor is configured to receive and process the current sense signal and the voltage sense signal to determine operational status information of the circuit breaker and determine power usage information of a load connected to the load output terminal.

A circuit breaker includes an electromechanical switch, a current sensor, a voltage sensor, and a processor. The electromechanical switch is serially connected between a line input terminal and a load output terminal of the circuit breaker, and configured to be placed in a switched-closed state or a switched-open state. The current sensor is configured to sense a magnitude of current flowing in a path between the line input and load output terminals and generate a current sense signal. The voltage sensor is configured to sense a magnitude of voltage at a point on the path between the line input and load output terminals and generate a voltage sense signal. The processor is configured to receive and process the current sense signal and the voltage sense signal to determine operational status information of the circuit breaker and determine power usage information of a load connected to the load output terminal.

An electric safety circuit for an aircraft DC power supply circuit includes a first electric line connecting a first electric pole of a main DC power supply with a first electric connector of an electric load; a second electric line connecting a second electric pole of the main DC power supply with a second electric connector of the electric load; at least one electric safety switch arranged in at least one of the first and second electric lines and configured for selectively interrupting any electric current flowing through said at least one electric line; a first electric coil arranged in the first electric line.

An electric safety circuit for an aircraft DC power supply circuit includes a first electric line connecting a first electric pole of a main DC power supply with a first electric connector of an electric load; a second electric line connecting a second electric pole of the main DC power supply with a second electric connector of the electric load; at least one electric safety switch arranged in at least one of the first and second electric lines and configured for selectively interrupting any electric current flowing through said at least one electric line; a first electric coil arranged in the first electric line.

A fault detector detects grounded-neutral faults. The fault detector is configured to: receive a first signal from a first induction circuit, the first induction circuit configured to detect a current imbalance between a line conductor and a neutral conductor; determine a first frequency and a first phase of a noise signal component of the first signal; output a noise cancellation signal to a primary side of the first induction circuit, the noise cancellation signal having the first frequency of the noise signal component and an opposite phase than the first phase of the noise signal component; and generate a trip signal based on determining that an impedance of the neutral conductor to ground is at or below a threshold level based upon the first signal received during the injection of the noise cancelation signal.

A ground fault circuit interrupter (GFCI) including separable contacts, a ground fault detection circuit structured to detect a ground fault based and to output a trip signal in response to detecting the ground fault, a trip circuit structured to trip open the separable contacts in response to the trip signal, a test button structured to be actuated by a user, a test unit structured to sequentially perform a GFCI self-test sequence and a ground fault test sequence in response to actuation of the test button, wherein the test unit is structured to determine whether the GFCI passed the GFCI self-test sequence and to output in an alarm signal in response to determining that the GFCI failed the GFCI self-test sequence, and an indicator structured to receive the alarm signal and to provide a visual or audible indication in response to receiving the alarm signal.

A feeding system feeds power from a power unit to a load via a feeding line and includes a protection device configured to operate by a current equal to or greater than a predetermined current; a monitoring unit configured to monitor whether an accident occurs in the feeding line; and a gate block unit configured to stop the feeding of the power of the power unit when the monitoring unit detects that an accident causing the protection device not to operate has occurred.

An apparatus for preventing an electric shock and a fire according to the present invention includes one or more failure detectors that have one end electrically connected to at least one of two or more power lines insulated from earth with a resistance value greater than or equal to a predetermined ground resistance value and a first neutral point having a potential between voltages of the two or more power lines, and the other end electrically connected to the earth, in which the failure detector detects a leakage current by forming a current path for the leakage current flowing from the two or more power lines or the first neutral point to the earth. According to the present disclosure, it is possible to prevent the electric shock and the occurrence of the fire due to the leakage current.

Passive monitoring the integrity of current sensing devices and associated circuitry in GFCI and AFCI protective devices is provided. A protection circuit interrupter employs a capacitively coupled noise signal obtained by an arrangement of one or both of line side arms relative to a Rogowski coil. The noise signal is monitored while the line and load sides of a protective circuit interrupter are disconnected, and the connection of the line and load sides disabled if the noise signal fails to correlate sufficiently to a reference noise cycle. When the line and load sides are connected, the RMS value of the observed current signal is monitored such that the line and load sides are disconnected if the observed current signal fails to meet an RMS threshold. The observed current signal is compensated by subtracting the reference noise cycle prior to monitoring for the fault condition applicable to the protective device.

A circuit for a circuit interrupter is provided. The circuit may in include a first SCR configured to receive a first trigger signal at a gate of the first SCR, a second SCR configured to receive a second trigger signal at a gate of the second SCR, and a third SCR configured to receive a third trigger signal at a gate of the third SCR. A cathode of the first SCR may be connected to an anode of the third SCR. A cathode of the second SCR and a cathode of the third SCR may be connected to a ground. Methods of operating a circuit interrupter and a circuit are also provided.