Patent ID: 6225810
Filing Date: 2001-05-01
Classification: G01R

Abstract:
An electrical cable shield integrity monitoring system for shielded wire in which the shield is in connection with a conducting structure or connected to itself such that a closed electrical current loop is formed, the integrity monitoring system comprising:(a) a test AC signal generator coupled to said loop using a magnetic (transformer) coupler which can be opened and then closed around the cable being tested;(b) a test, or ""sense"", winding placed on said coupler to measure the induced loop voltage;(c) a receiving circuit employing a magnetic (transformer) coupler to measure the induced loop current, in which the transformer voltage is forced to zero volts and which provides as an output voltage proportional to the loop current;(d) measuring apparatus in which the drive coupler winding voltage, the drive coupler sense winding voltage, and the voltage from the sense coupler current to voltage converter output are synchronously sampled to produce a discrete time series of numeric values, with each value scaled by the number of windings on the coupler from which it is derived.