Patent ID: 11875667
Assignee: CARRIER CORPORATION
Field: Control (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A fire system for a building, the fire system comprising:
a fire panel for monitoring the building and activating an alarm; and
a plurality of remote units electrically connected to the fire panel in a circuit having a loop configuration, at least some of the plurality of remote units comprising an indicating device for modulating a current in the circuit;
wherein the plurality of remote units are in communication with the fire panel in a master-slave relationship;
wherein the fire panel comprises a calibration module for polling each indicating device to obtain a current response value and for storing said current response values, the current response value of an indicating device being based on the amplitude of the current when modulated by that indicating device; and
the calibration module is configured to adjust a current threshold value based on an input from a user and the current response values, the current threshold value being the current response value at which the fire panel triggers an alarm, and the adjusted current threshold value being determined to be equal to the lowest current response value plus or minus a predetermined error threshold.