Patent · US Expired

Voltage monitor and alarm for power line

US4609914A · kind A · utility

15Cited by
5References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 19, 1984
Grant dateSep 2, 1986
Priority date
Expiry dateApr 19, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B21/182
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A small self-contained voltage monitoring device, which can be connected to a power line, has a display driver in circuit with a plurality of lamps to light one lamp at a time, depending on the power line voltage. A first oscillator in circuit with the display driver is actuated to operate a sound generator and alarm if the power line voltage falls outside a preset range. A second oscillator is in circuit with the first oscillator if the power line voltage is interrupted even momentarily, both oscillators are actuated by an auxiliary power source to generate a different sounding alarm. The alarm will continue to sound even if the power line voltage is restored until the auxiliary power source is manually deactivated.

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