An apparatus for testing the life of a leakage current protection device having a leakage current detection circuit and a trip mechanism having a switch device. In one embodiment, the apparatus a ground fault simulation unit, a fault detector of the leakage current detection circuit and the trip mechanism, and a life testing detection control unit having an MCU for controlling operation of the fault detector. In operation, a first signal (pulse signal) is sent to the gate of the switching device to generate a first voltage at the cathode of the switching device, a second signal is sent to the ground fault simulation unit to generate a simulated ground fault for the leakage current detection circuit to generate a second voltage at the gate of the switching device, and the first and second voltages are measured to determine whether a fault exists in the leakage current detection circuit and the trip mechanism.

Intelligent life testing methods and apparatus for leakage current protection

A system for determining whether arcing is present in an electrical circuit in response to a sensor signal corresponding to current in the circuit includes a circuit for analyzing the sensor signal to determine the presence of broadband noise in a predetermined range of frequencies, and producing a corresponding output signal. A controller processes the sensor signal and the output signal to determine current peaks and rise times and to determine, using the current peaks and rise times and the presence of broadband noise, whether an arcing fault is present in the circuit, by comparing data corresponding to the current peaks and rise times and broadband noise with preselected data indicative of an arcing fault. The circuit for analyzing and the controller are integrated onto a single application specific integrated circuit chip.

Arc fault circuit interrupter system

A method of determining whether arcing is present in an electrical circuit includes sensing a change in current in the circuit and developing a corresponding input signal, analyzing the input signal to determine the presence of broadband noise in a predetermined range of frequencies, and producing a corresponding output signal, and processing the input signal and the output signal in a predetermined fashion to determine whether an arcing fault is present in the circuit. The processing includes determining a type of load connected to the electrical circuit, based at least in part upon the input signal and the output signal.

Arc detection using load recognition, harmonic content and broadband noise

A method and system for determining whether arcing is present in an electrical circuit includes sensing a change in an alternating current in the circuit and developing a corresponding input signal, analyzing the input signal to determine the presence of broadband noise in a predetermined range of frequencies, and producing a corresponding output signal, and processing the input signal and the output signal in a predetermined fashion to determine whether an arcing fault is present in the circuit The processing includes determining a type of load connected to the electrical circuit, based at least in part upon the input signal and the output signal, and monitoring high frequency noise in a 20 KHz band for each ⅛ cycle of the alternating current

Load recognition and series arc detection using bandpass filter signatures

Disclosed herein is a method of and an apparatus for limiting electrical loads due to electrical equipment on an electric vehicle. In the electrical load limiting apparatus, a desired running distance is inputted by a desired running distance inputting device and a depth of discharge of a battery is detected by a battery condition detecting device. Ambient environment data for the electric vehicle are obtained from an illuminance sensor, a temperature sensor and a raindrop sensor. An arithmetic device is activated to determine and compute running conditions on the basis of the desired running distance, the depth of discharge and the ambient environment data. The electrical loads are controlled by an electrical load limiting device based on the result of the determination by the arithmetic device. Since the electrical loads are limited based on the running conditions, an accurate judgment can be made, based on the ambient environment, as to whether or not the electric vehicle can cover the inputted desired running distance.

Method of and apparatus for limiting electrical loads on an electric vehicle

An electrical power driver system with fault monitoring provision for both a self test mode and a normal operating mode. During the self test mode, the power driver is momentarily actuated during test intervals and its output compared to a predetermined value for providing self test fault indications. Each power driver is sampled and an indication provided of whether the fault is new or old in addition to providing a count of faults. During normal operation, monitoring circuitry provides indications of a plurality of fault types including over temperature, open circuit, short to ground, and short to voltage. A determination is made of whether each fault type is new or old and a count of faults provided. Output formatting provides indications of fault type, fault count, and whether the fault is intermittent or hard.

Melvin J. Sarnowsky

Papers

Smart power driver system for a motor vehicle