Local nondestructive status determination for concentric wire shield cables and cables sheathed in lead

The development of a technology for determining whether a lead-sheathed, single-phase cable was energized or not was previously reported. Two new developments are reported: a similar tool for concentric-wire-shield, plastic-sheathed cable and an electronic test method which is self-adapting to a wide range of resistivity in the outer screen layer. Included are details of a new, self-contained automatic plug-extractor for the lead cable. This plug extractor is coupled with a hand-held testing probe which utilizes the adaptive circuitry developed for the plastic cable