A control device for an electrical protection circuit for use in an alternating current system including a transformer is disclosed. An example system includes a first measurement probe, a second measurement probe configured to measure an electrical property within the electrical protection circuit, and a control module, including a processing device. The control module is configured to monitor a measurement from the first measurement probe and transmit a protection activation control signal to the switch assembly based on the measurement from the first measurement probe exceeding a first predetermined threshold. The control module is also configured to monitor a measurement from the second measurement probe and transmit a protection deactivation control signal to the switch assembly based on the measurement from the second measurement probe satisfying a second predetermined threshold.

A control device for an electrical protection circuit for use in an alternating current system including a transformer is disclosed. An example system includes a first measurement probe, a second measurement probe configured to measure an electrical property within the electrical protection circuit, and a control module, including a processing device. The control module is configured to monitor a measurement from the first measurement probe and transmit a protection activation control signal to the switch assembly based on the measurement from the first measurement probe exceeding a first predetermined threshold. The control module is also configured to monitor a measurement from the second measurement probe and transmit a protection deactivation control signal to the switch assembly based on the measurement from the second measurement probe satisfying a second predetermined threshold.

A detection scheme for temporary overvoltages and/or ground fault overvoltages in electric power systems is described. Current passing through a surge arrestor component of the power system is monitored. An algorithm for identifying one or more frequency components of the measured current signal is performed to screen out unwanted harmonics. In some embodiments, this is a frequency domain analysis. The frequency component(s) of the current signal is then compared to a calculated pickup current or pickup voltage of the system to determine if system protection steps should be undertaken.

A method and a system for detecting and processing one or more deviations from an acceptable electrical behavior at a point of interest in an electrical network, the system comprising a voltage sensor and/or a current sensor, a measurement-processor configured to process measurements received from the at least one of a voltage sensor and a current sensor, at least one storage for storing one or more acceptable values related to the electrical behavior at the point of interest, and a deviation-processor, the deviation processor is configured to receive one or more detected values related to the electrical behavior at a point in time at the point of interest and detect one or more deviations between the one or more acceptable values and the one or more detected values, and analyze one or more deviations between the one or more acceptable values and the one or more detected values.

A method and a system for detecting and processing one or more deviations from an acceptable electrical behavior at a point of interest in an electrical network, the system comprising a voltage sensor and/or a current sensor, a measurement-processor configured to process measurements received from the at least one of a voltage sensor and a current sensor, at least one storage for storing one or more acceptable values related to the electrical behavior at the point of interest, and a deviation-processor, the deviation processor is configured to receive one or more detected values related to the electrical behavior at a point in time at the point of interest and detect one or more deviations between the one or more acceptable values and the one or more detected values, and analyze one or more deviations between the one or more acceptable values and the one or more detected values.

An electrical device includes a first terminal structured to electrically connect to a power source; a second terminal structured to electrically connect to a load; a voltage sensor electrically connected to a point between the first and second terminals and being structured to sense a voltage at the point between the first and second terminals; a switch electrically connected between the first terminal and the second terminal; and a control unit structured to detect a power quality event in the power flowing between the first and second terminals based on the sensed voltage and to control a state of the switch based on the detected power quality event.

An electrical device includes a first terminal structured to electrically connect to a power source; a second terminal structured to electrically connect to a load; a voltage sensor electrically connected to a point between the first and second terminals and being structured to sense a voltage at the point between the first and second terminals; a switch electrically connected between the first terminal and the second terminal; and a control unit structured to detect a power quality event in the power flowing between the first and second terminals based on the sensed voltage and to control a state of the switch based on the detected power quality event.

A receptacle including an electronic processor configured to receive information from an external load and determine, from the information, an operation profile of the external load. The electronic processor analyzes a present operation of the external load and discontinues power to the external load when a present operation of the external load differs from the operational profile.

A receptacle including an electronic processor configured to receive information from an external load and determine, from the information, an operation profile of the external load. The electronic processor analyzes a present operation of the external load and discontinues power to the external load when a present operation of the external load differs from the operational profile.

An image forming device that forms an image on a medium, includes: a heater that heats the medium; a control unit that controls the heater; a first path that receives input voltage from an external power supply, converts the input voltage into desired voltage, and supplies the desired voltage to the control unit; a second path that divides the input voltage received by the first path and supplies the input voltage to the heater; a control element that is connected to the second path and controls ON/OFF switching of the heater according to control from the control unit; and a disconnection unit that disconnects the second path depending on condition of the input voltage.