Patent · US Expired

Systems for power interruption detection

US5784441A · kind A · utility

24Cited by
22References
36Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 3, 1993
Grant dateJul 21, 1998
Priority date
Expiry dateNov 3, 2013

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M11/04
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A method for monitoring a condition, such as the presence of electrical power, at a remote location and for generating a telephone call on to a telephone line that delivers to a central control unit notification of a change in the monitored condition in the form of a set of unique identifying signals. According to the method, the condition is monitored at the remote location and is sensed for changes in the condition from a first state to a second state. Responsive to a change in the condition to the second state, the telephone line is tested and a line availability signal generated. Responsive to indicia of line availability, the line is selectively seized. Signals are generated on to the telephone line representative of a first telephone number to address the first control location, the signals representative the first telephone number correspond to the change in the monitored condition and signals representative of the telephone number assigned to the remote location are generated on to the telephone line by the interexchange carrier network.

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