Detection of electric charge that might come from a human connected to an isolated electrical line, uses measurement of changes in impedance obtained by applying test voltage to detect fault or human in contact with line

摘要

The charge detector is connected to an isolated electric line, and a variable voltage is injected into the line to cause a variation in impedance. The impedance variation is measured (30) and variation (dZ) determined. The variation is processed (31, 35) to determine whether the impedance change corresponds to a differential fault (32) or contact with a human body (34).