Patent · US Expired

Current sensing alarm arrangement for monitoring the presence of high voltage

US4755805A · kind A · utility

15Cited by
3References
2Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 22, 1986
Grant dateJul 5, 1988
Priority date
Expiry dateMay 22, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R19/16576
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A system in which an electrically conductive boring device is caused to move through the ground to provide an underground tunnel, to install underground utilities, or for any other reason. A technique for detecting if the boring device electrically engages an underground source of high voltage such as an existing underground utility line. This arrangement, is also suitable for detecting if other electrically conductive apparatus, structural member, or like means engages a similar underground source of high voltage includes means defining an electrically conductive path leading from the boring device or other such member to a grounding point sufficient to reduce to a negligible level any high voltage to which the device or like member may be subjected. The present technique monitors the current through the grounding path and indicates if the current level through the path reaches a predetermined threshold level which is selected to correspond with the presence of high voltage.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.