Honeywell International Inc.
DETECTING FAULTS ON A SPUR WIRED ALARM CIRCUIT

Abstract:

Devices, methods, and systems for detecting faults on a spur wired alarm circuit are described herein. One system includes a bipolar capacitor coupled to a last device on a spur wired alarm circuit, a current source coupled to the spur wired alarm circuit, and a controller configured to operate the current source to provide a current to the spur wired alarm circuit, determine a corresponding voltage drop across the spur wired alarm circuit, determine a resistance of the spur wired alarm circuit based on the determined voltage drop, and determine whether a fault has occurred on the spur wired alarm circuit based on the determined resistance.