Circuit interrupters with opto-electronic and/or acoustic systems that can measure displacement over time, optionally along with interrupt current measurements, during an opening and closing event with signal data collected when triggered by a breaker open or breaker close event.

A method includes measuring, by at least one processor, a time at which control circuitry sends an instruction to a switch structured to control transmission of electrical power. The method further includes sensing, by at least one sensor, a change in position of the switch in response to the instruction, and determining, by the at least one processor, a delay between the time at which the control circuitry sends the instruction and a time at which the change in position occurs. The method still further includes recording, by the at least one processor, the delay in a delay measurement queue and taking, by the at least one processor, an action with respect to the switch in response to the delay measurement queue.

A method includes measuring, by at least one processor, a time at which control circuitry sends an instruction to a switch structured to control transmission of electrical power. The method further includes sensing, by at least one sensor, a change in position of the switch in response to the instruction, and determining, by the at least one processor, a delay between the time at which the control circuitry sends the instruction and a time at which the change in position occurs. The method still further includes recording, by the at least one processor, the delay in a delay measurement queue and taking, by the at least one processor, an action with respect to the switch in response to the delay measurement queue.

A ground fault circuit interrupter (GFCI) breaker testing system can include an enclosure having at least one wall that forms a cavity. The system can also include at least one GFCI breaker disposed within the cavity. The system can further include a sensing circuit assembly having at least one switch, where the at least one switch is electrically coupled to the at least one GFCI breaker. The system can also include a user interface assembly disposed, at least in part, outside the cavity, where the user interface assembly is coupled to the sensing circuit assembly, where the user interface assembly instructs the at least one switch to test the at least one GFCI breaker.

A circuit interrupter including a line conductor, a neutral conductor, separable contacts, an operating mechanism structured to trip open the separable contacts, a magnetic trip actuator structured to cause the operating mechanism to trip open the separable contacts in response to a short-circuit between the line and neutral conductors, a protection circuit including a self-test circuit structured to perform a self-test and to output a signal in response to failing the self-test, and an electrical component electrically connected between the line and neutral conductors and having an open state and a closed state. The electrical component is structured to switch from the open state to the closed state and cause a short-circuit between the line and neutral conductors in response to receiving the signal from the self-test circuit.

An electrical system can include a diagnostic device that generates a first test signal. The electrical system can also include multiple energy transfer links coupled to the diagnostic device, where the first test signals flows through a first subset of the energy transfer links. The electrical system can further include a first monitoring device coupled to the first subset of energy transfer links, where the first monitoring device receives the first test signal from the diagnostic device through the first subset of the energy transfer links. The electrical system can also include a first electrical device coupled to the first monitoring device. The first monitoring device can implement a first test procedure based on the first test signal, where the first test procedure helps determine a first condition of the first electrical device.

A tester for a frequency-dependent ground fault interrupt wiring device, including: a tester circuit, including: a switch disposed between a first terminal and a second terminal, wherein a leakage current flows through a leakage path between the first terminal and the second terminal when a voltage is applied across the first terminal and the second terminal, a magnitude of the leakage current being determined, at least in part, by a conductivity of the switch; and a waveform generator configured to generate a periodic output signal having a frequency, wherein the switch is driven to modulate the magnitude of the leakage current such that the leakage current has a frequency substantially equal to a frequency of the waveform generator.

An apparatus and method for diagnosing damage of a switch in a battery protection circuit include a battery protection circuit including a first switch and a second switch connected to a battery pack and a switch damage diagnosing device for measuring in the battery protection circuit and for diagnosing whether any one of the first switch and the second switch is damaged. The source terminal of the first switch and the source terminal of the second switch can be connected to a common source, which can diagnose whether or not the switch is damaged only by measuring the voltage at a certain point without measuring a current.

A circuit breaker monitoring system and method includes a vibration sensor, a processing unit, and an output unit. The vibration sensor is configured to be mounted to a circuit breaker and to acquire a temporal vibration signal over at least a temporal portion of a closing operation of the circuit breaker. The closing operation comprises: initiation of the closing operation; latch release; movement of a moveable contact towards a fixed contact; contact touch of the moveable contact with the fixed contact; stop of movement of the moveable contact. The sensor provides the temporal vibration signal to the processing unit, which determines a plurality of physical switch events and corresponding plurality of time points of the plurality of physical switch events over the closing operation of the circuit breaker.

A fault current limiter may include a current limiting leg to transmit a first current and a control leg in parallel with the current limiting leg, the control leg to transmit a second current. The control leg may include a plurality of power electronic modules arranged in electrical series with one another, and a bypass power electronic module arranged in electrical series with the plurality of power electronic modules. The control leg may further include a plurality of current monitors arranged electrically in series with the plurality of power electronic modules and the bypass power electronic module, and at least one triggering circuit, wherein the plurality of current monitors is electrically coupled to the at least one triggering circuit, and wherein the at least one triggering circuit is coupled to at least one of: the plurality of power electronic modules, and the bypass power electronic module.