Patent · US Expired

Protective relay circuit for detecting arcing faults on low-voltage spot networks

US4639817A · kind A · utility

60Cited by
5References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 15, 1984
Grant dateJan 27, 1987
Priority date
Expiry dateMay 15, 2004

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H1/0015
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A protective relay for detecting power arcing faults on a low-voltage spot network. The protective relay can monitor the voltage difference between each phase conductor, the voltage difference between each phase conductor and the neutral conductor, or the current on each phase conductor. Using one of these three sets of values, the protective relay first filters the input signal so that only frequencies indicative of a power arcing fault on the low-voltage spot network are analyzed. The signals passed by the filter are amplified, rectified, and averaged and the peak of each signal detected. If the peak has a duration longer than a predetermined value, a fault indication is provided.

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