Patent · US Expired

Sensor test circuit of an alarm system

US4518952A · kind A · utility

15Cited by
2References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 29, 1983
Grant dateMay 21, 1985
Priority date
Expiry dateAug 29, 2003

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B29/14
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

When a receiver supplies both an address signal and a test instruction signal to a given terminal unit, a test voltage generator forming a sensor test circuit of this terminal unit supplies a predetermined test voltage to a corresponding sensor. This sensor generates an analog signal obtained by superimposing the test voltage on the normally detected voltage. The analog signal is A/D-converted, and a resultant digital signal is received by the receiver, thereby allowing a test for operating conditions of any sensor at the site of the receiver. The test voltage generator may generate a plurality of stepwise voltage components to readily check operating characteristics (e.g., overload characteristic) of the sensor.

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