Multizone intruder detection system with forced walk-test
US5057816A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 1990 |
| Grant date | Oct 15, 1991 |
| Priority date | — |
| Expiry date | Aug 31, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B29/14
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A multizone intruder detection system comprises a supervisory circuit for verifying, while the system is disarmed, that each of a plurality of intrusion sensors is, indeed, functional. The supervisory circuit inhibits rearming of a disarmed system until it determines that each sensor has successfully operated within a relatively brief time interval just prior to the time an attempt is made to arm the system. A timing circuit, activated by a preliminary arm signal, operates to establish a time window (e.g. 10 minutes) within which the operability of each sensor must be verified (i.e. walk-tested) as a precondition to system arming. Preferably, the timing circuit is reset by each sensor alarm output, whereby the system user is given the full time window to walk-test each sensor. By virtue of the invention, sensor sabotage in a disarmed system can be mitigated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.