Granted Patent
Utility
US 4,954,809 · App. 07/345,596
Continuity-isolation testing for class A wiring in fire alarm system
Inventors:
Robert W. Right, Simon Carter
Patented Case
View Patent ↗
Granted: Sep 4, 1990
Filed: May 1, 1989
Inventors
Robert W. Right
Simon Carter
Assignee (at issue)
Federal Signal Corporation
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.