A wiring device including an interrupting device and a controller. The interrupting device electrically connects one or more line terminals to one or more load terminals when the interrupting device is in a reset condition and disconnects the line terminals from the load terminals when the interrupting device is in a tripped condition. The controller is configured to, determine a frequency of an input voltage at the one or more line terminals, determine whether the frequency is within a predetermined range, and when the frequency is within the predetermined range, perform a test of the wiring device.

An apparatus and a method for measuring an insulation resistance of a vehicle provided with a high voltage system including a battery and a plurality of high voltage electrical components operated by receiving power stored in the battery, includes a controller configured to determine a stray capacitance based on the high voltage electrical components electrically connected to the battery and to determine a measurement period for measuring the insulation resistance of the vehicle based on the determined stray capacitance.

An apparatus and a method for measuring an insulation resistance of a vehicle provided with a high voltage system including a battery and a plurality of high voltage electrical components operated by receiving power stored in the battery, includes a controller configured to determine a stray capacitance based on the high voltage electrical components electrically connected to the battery and to determine a measurement period for measuring the insulation resistance of the vehicle based on the determined stray capacitance.

The aim of the invention is to prevent undesired false triggering of a safety device, which protects a person from electric shock as a result of unintentional contact with voltage-carrying or current-carrying parts. This aim is achieved in that a triggering sensitivity (E.sub.A) of the safety device is changed depending on a determined body resistance (R.sub.K) of the person wearing the safety device.

The aim of the invention is to prevent undesired false triggering of a safety device, which protects a person from electric shock as a result of unintentional contact with voltage-carrying or current-carrying parts. This aim is achieved in that a triggering sensitivity (E.sub.A) of the safety device is changed depending on a determined body resistance (R.sub.K) of the person wearing the safety device.

A GFCI includes a current sensor system providing a current sensor signal indicating a leakage current of the AC power system. At least one signal conditioning channel conditions the current sensor signal to provide a conditioned current sensor signal. An integrated circuit-based controller is configured to receive the conditioned current sensor signal. The integrated circuit-based controller is configured to execute instructions stored in at least one nontransitory memory medium to determine at least one frequency value and at least one magnitude value of the conditioned current sensor signal, evaluate a trip condition in response to the at least one frequency value and the at least one magnitude value, and provide a fault trip signal in response to evaluation of the trip condition. A circuit breaker mechanism is configured to open a circuit of the AC power system in response to the fault trip signal.

A GFCI includes a current sensor system providing a current sensor signal indicating a leakage current of the AC power system. At least one signal conditioning channel conditions the current sensor signal to provide a conditioned current sensor signal. An integrated circuit-based controller is configured to receive the conditioned current sensor signal. The integrated circuit-based controller is configured to execute instructions stored in at least one nontransitory memory medium to determine at least one frequency value and at least one magnitude value of the conditioned current sensor signal, evaluate a trip condition in response to the at least one frequency value and the at least one magnitude value, and provide a fault trip signal in response to evaluation of the trip condition. A circuit breaker mechanism is configured to open a circuit of the AC power system in response to the fault trip signal.

Circuits integrated or integrable with a photovoltaic panel to provide built-in functionality to the photovoltaic panel including safety features such as arc detection and elimination, ground fault detection and elimination, reverse current protection, monitoring of the performance of the photovoltaic panel, transmission of the monitored parameters and theft prevention of the photovoltaic panel. The circuits may avoid power conversion, for instance DC/DC power conversion, may avoid performing maximum power tracking to include a minimum number of components and thereby increase overall reliability.

Circuits integrated or integrable with a photovoltaic panel to provide built-in functionality to the photovoltaic panel including safety features such as arc detection and elimination, ground fault detection and elimination, reverse current protection, monitoring of the performance of the photovoltaic panel, transmission of the monitored parameters and theft prevention of the photovoltaic panel. The circuits may avoid power conversion, for instance DC/DC power conversion, may avoid performing maximum power tracking to include a minimum number of components and thereby increase overall reliability.

Provided is an apparatus and method for protecting against unsafe electric current conditions. A protections circuit may be used in a device, such as an electric grill, that has one or more electric loads, such as heating elements. The protection circuit may protect against various failure scenarios, including, without limitation, instances of ground fault, over current, driver failure, and failure of a microprocessor. In response to a failure, the protection circuit may trip a latch relay or disable a triac driver to stop current from flowing.