Patent · US Expired

Faulted current indicators with improved signal to noise ratios

US5055771A · kind A · utility

9Cited by
6References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 21, 1989
Grant dateOct 8, 1991
Priority date
Expiry dateAug 21, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R15/183
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A sensor in a faulted current indicator includes a coil and a magnetic arrangement passing through the coil and around a current-carrying conductor for coupling the coil to the conductor. The magnetic arrangement has given magnetic reluctance and forms a higher reluctance section, such as a gap, within the coil. Preferably the magnetic arrangement includes a U-shaped laminate and two core laminations joined to the U-shaped laminate by two gaps to allow for installation around the conductor. The ferromagnetic plate outside the coil shields the coil. The sensitivity of the sensor is increased by coating the inner surface of the U-shaped laminate and the core lamination surfaces contacting the U-shaped laminate with a high Ni content ferromagnetic material.

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