Abstract: Apparatuses and methods for passively monitoring the integrity of current sensing devices and associated circuitry in protective devices such as Ground Fault Circuit Interrupters and Arc Fault Circuit Interrupters are provided. A protection circuit interrupter employs a capacitively coupled noise signal obtained by an arrangement of one or both of the line side arms relative to a Rogowski coil. The noise signal is monitored while the line and load sides of a protective circuit interrupter are disconnected, and the connection of the line and load sides disabled if the noise signal fails to correlate sufficiently to a reference noise cycle. When the line and load sides are connected, the RMS value of the observed current signal is monitored such that the line and load sides are disconnected if the observed current signal fails to meet an RMS threshold.

Abstract: Method and system allowing more accurate detection and identification of unwanted arcing include novel processing of signal voltage representing recovered power-line current. In one implementation, arc-faults are detected based on numerical analysis where individual cycles of line voltage and current are observed and data collected during each cycle is processed to estimate likelihood of presence of arc-event within each individual cycle based on pre-defined number of arc-events occurring within pre-defined number of contiguous cycles.

Abstract: A system and method for automatic gain and slope equalization for provisioning telephone circuits is provided. A first unit is installed at the company end of a copper pair transmission line. A second unit is installed between customer premises equipment (CPE) and the copper pair transmission line. The second unit is programmed to disconnect the CPE, and to transmit a test signal, preferably comprising a square wave with a known amplitude and fundamental frequency of 1 kHz. The signal is received at the first unit, and the fundamental frequency and odd harmonic frequencies are analyzed. Based on the analysis, the first unit thereafter compensates for impairments in the transmission line. The test procedure can be initiated from either the first unit or the second unit. The first unit is programmed to produce a command sequence, preferably comprising a series of DC voltages applied to the tip and ring leads, and received at the second unit.