Abstract: Aspects of an electrical safety device that provides detection of miswiring of line and load connection pairs are presented. In an example, the device includes a differential current detector through which are routed a live current path and a neutral current path coupling the line and load connection pairs. The device also includes a selectable conducting path that, when selected, circumvents the differential current detector while coupling one of a line live connection to a load live connection or a line neutral connection to a load neutral connection of the connection pairs. The device further includes a control circuit that determines, via the differential current detector, while the conducting path is selected, a differential current defined by a difference in currents on the live and neutral current paths, and interrupts at least one of the live and neutral current paths in response to the differential current not exceeding a threshold value.

Abstract: A single wound single current transformer impedance measurement circuit for determining a circuit element parameter in a ground fault circuit interrupter circuit. The circuit includes a transconductance amplifier having first and second input terminals and first and second output terminals. In an embodiment, a first detector has input terminal coupled to the first output terminal of the transconductance amplifier and another input terminal coupled for receiving a first electrical signal. A second detector has a terminal coupled to the second output terminal of the transconductance amplifier and an input terminal coupled for receiving the first electrical signal. Alternatively, the second detector has an input terminal coupled to the first output terminal of the transconductance amplifier and another input terminal coupled for receiving the first electrical signal.

Abstract: A ground fault interrupter circuit and a method for operating a ground fault interrupter that includes configuring the ground fault interrupter to perform a plurality of self tests. The ground fault interrupter may be configured to perform a ground fault self test, a grounded-neutral self test, and a trip circuit self test.

Abstract: A method for operating a ground fault circuit interrupter. In accordance with an embodiment, an operating parameter of the ground fault circuit interrupter can be adjusted in response to an alternating current line signal and a reference signal. In accordance with another embodiment a plurality of indicator signals are generated in response to an alternating current signal. The indicator signals are used to generate one or more control signals and at least one of the control signals is used to control a control a ground fault circuit interrupter.

Abstract: A single wound single current transformer impedance measurement circuit for determining a circuit element parameter in a ground fault circuit interrupter circuit. The circuit includes a transconductance amplifier having first and second input terminals and first and second output terminals. In an embodiment, a first detector has input terminal coupled to the first output terminal of the transconductance amplifier and another input terminal coupled for receiving a first electrical signal. A second detector has a terminal coupled to the second output terminal of the transconductance amplifier and an input terminal coupled for receiving the first electrical signal. Alternatively, the second detector has an input terminal coupled to the first output terminal of the transconductance amplifier and another input terminal coupled for receiving the first electrical signal.

Abstract: A method and circuit for dynamically correcting offsets associated with an AC power system. In an embodiment, a first offset current generated in response to a ground to neutral fault stimulus is decreased and a second offset current generated in response to a differential fault stimulus is decreased. In another embodiment, the circuit includes an offset correction circuit that has one of a chopper circuit or an auto-zeroing circuit. An amplifier is connected to the offset correction circuit and an output connected to the offset correction circuit. A signal generator is switchably coupled to a first input of the offset correction circuit and a bias generator is switchably coupled to the first input of the offset correction circuit.

Abstract: A method for determining a circuit element parameter in a ground fault circuit interrupter circuit. An electrical signal provided to a first node is used to generate another electrical signal at a second node. The electrical signal at the second node is multiplexed with a modulation signal to generate a modulated signal that is then filtered and converted into a digital representation of a portion of the circuit element parameter. The electrical signal at the second node is multiplexed with the modulation signal after it has been phase shifted to produce a modulated signal that is filter and converted into a digital representation of another portion of the circuit element parameter. In another aspect, a slope based solenoid self-test method is used for self-testing in a GFCI circuit. Alternatively, a method for determining a wiring fault is provided using a digital filter.

Abstract: A method and circuit for determining a circuit element parameter in a ground fault circuit interrupter circuit. An electrical signal provided to a first node is used to generate another electrical signal at a second node. The electrical signal at the second node is multiplexed with a modulation signal to generate a modulated signal that is then filtered and converted into a digital representation of a portion of the circuit element parameter. The electrical signal at the second node is multiplexed with the modulation signal after it has been phase shifted to produce a modulated signal that is filter and converted into a digital representation of another portion of the circuit element parameter. In another aspect, a slope based solenoid self-test method is used for self-testing in a GFCI circuit. Alternatively, a method for determining a wiring fault is provided using a digital filter.

Abstract: Aspects of an electrical safety device that provides detection of miswiring of line and load connection pairs are presented. In an example, the device includes a differential current detector through which are routed a live current path and a neutral current path coupling the line and load connection pairs. The device also includes a selectable conducting path that, when selected, circumvents the differential current detector while coupling one of a line live connection to a load live connection or a line neutral connection to a load neutral connection of the connection pairs. The device further includes a control circuit that determines, via the differential current detector, while the conducting path is selected, a differential current defined by a difference in currents on the live and neutral current paths, and interrupts at least one of the live and neutral current paths in response to the differential current not exceeding a threshold value.

Abstract: A ground fault interrupter circuit and a method for operating a ground fault interrupter that includes configuring the ground fault interrupter to perform a plurality of self tests. The ground fault interrupter may be configured to perform a ground fault self test, a grounded-neutral self test, and a trip circuit self test.

Abstract: A method for determining a circuit element parameter in a ground fault circuit interrupter circuit. An electrical signal provided to a first node is used to generate another electrical signal at a second node. The electrical signal at the second node is multiplexed with a modulation signal to generate a modulated signal that is then filtered and converted into a digital representation of a portion of the circuit element parameter. The electrical signal at the second node is multiplexed with the modulation signal after it has been phase shifted to produce a modulated signal that is filter and converted into a digital representation of another portion of the circuit element parameter. In another aspect, a slope based solenoid self-test method is used for self-testing in a GFCI circuit. Alternatively, a method for determining a wiring fault is provided using a digital filter.

Abstract: A method for operating a ground fault circuit interrupter. In accordance with an embodiment, an operating parameter of the ground fault circuit interrupter can be adjusted in response to an alternating current line signal and a reference signal. In accordance with another embodiment a plurality of indicator signals are generated in response to an alternating current signal. The indicator signals are used to generate one or more control signals and at least one of the control signals is used to control a control a ground fault circuit interrupter.

Abstract: A method and circuit for determining a circuit element parameter in a ground fault circuit interrupter circuit. An electrical signal provided to a first node is used to generate another electrical signal at a second node. The electrical signal at the second node is multiplexed with a modulation signal to generate a modulated signal that is then filtered and converted into a digital representation of a portion of the circuit element parameter. The electrical signal at the second node is multiplexed with the modulation signal after it has been phase shifted to produce a modulated signal that is filter and converted into a digital representation of another portion of the circuit element parameter. In another aspect, a slope based solenoid self-test method is used for self-testing in a GFCI circuit. Alternatively, a method for determining a wiring fault is provided using a digital filter.

Abstract: A method and circuit for determining a circuit element parameter in a ground fault circuit interrupter circuit. An electrical signal provided to a first node is used to generate another electrical signal at a second node. The electrical signal at the second node is multiplexed with a modulation signal to generate a modulated signal that is then filtered and converted into a digital representation of a portion of the circuit element parameter. The electrical signal at the second node is multiplexed with the modulation signal after it has been phase shifted to produce a modulated signal that is filter and converted into a digital representation of another portion of the circuit element parameter. In another aspect, a slope based solenoid self-test method is used for self-testing in a GFCI circuit. Alternatively, a method for determining a wiring fault is provided using a digital filter.

Abstract: A method and circuit for determining a circuit element parameter in a ground fault circuit interrupter circuit. An electrical signal provided to a first node is used to generate another electrical signal at a second node. The electrical signal at the second node is multiplexed with a modulation signal to generate a modulated signal that is then filtered and converted into a digital representation of a portion of the circuit element parameter. The electrical signal at the second node is multiplexed with the modulation signal after it has been phase shifted to produce a modulated signal that is filter and converted into a digital representation of another portion of the circuit element parameter. In another aspect, a slope based solenoid self-test method is used for self-testing in a GFCI circuit. Alternatively, a method for determining a wiring fault is provided using a digital filter.