A power pedestal includes a pedestal member including a base structured to be fixed to a platform and an enclosure extending from said base, a plurality of input power terminals mounted to said pedestal member and structured to be electrically connected to a power source, a number of output power receptacles mounted to said enclosure, a number of circuit interrupters having a ground fault detection capability and being structured to output an alarm signal in response to detecting a ground fault, a relay structured to receive the alarm signal from the circuit interrupters and to output an indicator signal, and an indicator unit structured to receive the indicator signal from the relay, the indicator unit including an indicator and being structured to illuminate the indicator in response to receiving the indicator signal.

A power pedestal includes a pedestal member including a base structured to be fixed to a platform and an enclosure extending from said base, a plurality of input power terminals mounted to said pedestal member and structured to be electrically connected to a power source, a number of output power receptacles mounted to said enclosure, a number of circuit interrupters having a ground fault detection capability and being structured to output an alarm signal in response to detecting a ground fault, a relay structured to receive the alarm signal from the circuit interrupters and to output an indicator signal, and an indicator unit structured to receive the indicator signal from the relay, the indicator unit including an indicator and being structured to illuminate the indicator in response to receiving the indicator signal.

In a method of warning of a hazardous electrical condition at a dock with wiring coupled to a voltage source via a dock breaker, an electric voltage between a ground and at least one of the dock frame or the water is detected. A plurality of voltage values of the electric voltage is stored. When at least two successive voltage values of the plurality voltage values exceeds a baseline safe voltage by a preset margin, then a shock warning signal is asserted, a dock breaker is opened and a shock warning indication is transmitted to a remote unit via a communication chipset. When at a voltage is sensed in the dock wiring system after the dock breaker has been opened, then a faulty dock breaker warning indication is transmitted to the remote unit via the communication chipset.

The present invention is directed towards a serially connected micro-inverter (SCMI) system comprising a plurality of power sources for producing DC power, a plurality of micro-inverters, where each micro-inverter is coupled to at least one power source of the plurality of power sources, for converting the DC power into AC power, an AC bus for coupling the plurality of micro-inverters in series to form a string and for coupling the AC power an AC line; and a controller, coupled to the string, for measuring an output signal of one or more strings of series coupled micro-inverters, comparing the measured output signal to a desired signal for the string; and adjusting a phase angle of an output from each micro-inverter in the one or more strings until a difference between the measured output signal and the desired signal is less than a predetermined threshold value.

The present invention is directed towards a serially connected micro-inverter (SCMI) system comprising a plurality of power sources for producing DC power, a plurality of micro-inverters, where each micro-inverter is coupled to at least one power source of the plurality of power sources, for converting the DC power into AC power, an AC bus for coupling the plurality of micro-inverters in series to form a string and for coupling the AC power an AC line; and a controller, coupled to the string, for measuring an output signal of one or more strings of series coupled micro-inverters, comparing the measured output signal to a desired signal for the string; and adjusting a phase angle of an output from each micro-inverter in the one or more strings until a difference between the measured output signal and the desired signal is less than a predetermined threshold value.

A line-to-ground fault location detector detects, based on a difference between a current flowing from a power transmission circuit to a load circuit, and a current flowing from the load circuit to the power transmission circuit, whether a line-to-ground fault is occurring at a power-transmission-circuit side or a load-circuit side. A contactor controller opens a first contactor when the load circuit detects the occurrence of the line-to-ground fault, and when a line-to-ground fault location detector detects that a location of the line-to-ground fault is at the power-transmission-circuit side, the contactor controller maintains the open state of the first contactor even if an operation to instruct closing of the first contactor is made after the first contactor is opened.

A line-to-ground fault location detector detects, based on a difference between a current flowing from a power transmission circuit to a load circuit, and a current flowing from the load circuit to the power transmission circuit, whether a line-to-ground fault is occurring at a power-transmission-circuit side or a load-circuit side. A contactor controller opens a first contactor when the load circuit detects the occurrence of the line-to-ground fault, and when a line-to-ground fault location detector detects that a location of the line-to-ground fault is at the power-transmission-circuit side, the contactor controller maintains the open state of the first contactor even if an operation to instruct closing of the first contactor is made after the first contactor is opened.

A device for detecting a fault in an AC supply comprising a detection circuit for detecting a fault in an AC supply to a load and providing a corresponding output. A disconnect circuit disconnects the load from the supply in response to an output from the detection circuit. The device also includes a generator of intermittent test pulses, and a test circuit coupled to the detection circuit and containing a first solid state switch. Each test pulse turns on the solid state switch for the duration of the test pulse so that a current simulating the fault flows intermittently in the test circuit and a corresponding output is provided by the detection circuit. The device further comprising means to disable the disconnect circuit in response to each test pulse.

A circuit interrupter includes a line conductor, a neutral conductor, separable contacts structured to open to interrupt current flowing through the line and neutral conductors, a circuit interrupter circuit structured to detect a fault based on current flowing through the line and neutral conductors and to output a trip signal in response to detecting the fault, a trip circuit structured to trip open the separable contacts in response to the trip signal, and an audible indicator circuit structured to output an audible sound in response to the trip circuit tripping open the separable contacts.

A circuit interrupter includes a line conductor, a neutral conductor, separable contacts structured to open to interrupt current flowing through the line and neutral conductors, a circuit interrupter circuit structured to detect a fault based on current flowing through the line and neutral conductors and to output a trip signal in response to detecting the fault, a trip circuit structured to trip open the separable contacts in response to the trip signal, and an audible indicator circuit structured to output an audible sound in response to the trip circuit tripping open the separable contacts.