Alarm system

Details Alarm system Alarm system

1976-12-29

1979-03-13

Caldwell, Sr., John W.

Communications: electrical

Condition responsive indicating system

340505, 340518, G08B 2600

Patent

active

041445287

ABSTRACT:
An alarm system includes: (1) a central station having power generating means and alarm registering means, and (2) a plurality of alarm-producing systems in locations remote from the central system, each electrically connected to the central station through a single pair of conductors, and each including circuitry for producing up to eight separate alarm conditions as the power generating means alternately impresses a first predetermined DC voltage on each pair of conductors simultaneously, then interrupts voltage to all conductors simultaneously, impresses a second predetermined DC voltage only on the first of each pair of conductors simultaneously, and again interrupts voltage to all conductors simultaneously.

REFERENCES:
patent: 3307166 (1967-02-01), Slack et al.
patent: 3618069 (1971-11-01), Evans
patent: 3641547 (1972-02-01), Reiss et al.
patent: 3699569 (1972-10-01), Lee
patent: 3702474 (1972-11-01), Fink et al.
patent: 3706987 (1972-12-01), West et al.
patent: 3716834 (1973-02-01), Adams
patent: 3811126 (1974-05-01), Winger

Affiliated with

Also associated with

Rating

Alarm system does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Alarm system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Alarm system will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2373961