A short-circuit isolator includes a switch configured to selectively interrupt an electrical circuit connected to the short-circuit isolator. The short-circuit isolator is configured to cause the switch to interrupt the electrical circuit when a current at the short-circuit isolator exceeds a current threshold and at least one of a voltage at the short-circuit isolator is below a voltage threshold or a resistance of the electrical circuit measured at the short-circuit isolator is below a resistance threshold.

A fire detector is connected to a loop transmission line connected to a receiver. When the loop transmission line is normal, a transmission unit is connected to the fire detector. When a disconnection failure occurs, a disconnection monitoring unit turns on switching circuits to connect the end of the loop transmission line to the transmission unit, and the receiver connects to the fire detector from both ends of the loop transmission line. An input/output switching booster is inserted and connected in the middle of the loop transmission line, and when the start side transmission line is disconnected and the switching circuits are turned on, the input/output is switched. Accordingly, the input/output switching booster amplifies the down signal input from the terminal side transmission line and outputs it to the start side transmission line and at the same time amplifies the up signal input from the start side transmission line.

A fire system 10 for a building is provided, the fire system 10 including a fire panel 12 for monitoring the building and activating an alarm; and a plurality of remote units 14, 16, 18 electrically connected to the fire panel 12 in a circuit 20 having a loop configuration. At least some of the plurality of remote units 14, 16, 18 including an indicating device 14, 18 for modulating a current in the circuit 20. The plurality of remote units 14, 16, 18 are in communication with the fire panel 12 in a master-slave relationship. The fire panel 12 includes a calibration module 22 for polling each indicating device 14, 18 to obtain a current response value and for storing said current response values, the current response value of an indicating device 14, 18 being based on the amplitude of the current when modulated by that indicating device.

The present disclosure is directed to methods and systems for providing information about a target based on pulse widths. The information can be provided in a formatted output signal which uses a pulse width protocol to code information by varying amplitudes and widths of successive pulses in an output signal pulse train portion. The method includes detecting a first feature of the target and in response to detecting the first feature, generating an output signal pulse train portion comprising two or more pulses with at least two of the pulses having different amplitudes and each of the two or more pulses having a width corresponding to a logic value. The widths of the two or more pulses in the output signal pulse train portion can be measured in response to the detected first feature reaching a first amplitude threshold, whereby the widths can correspond to different logic values.

Disclosed is a hazard detector connected to a circuit that has: a plurality of circuit ends and a plurality of detectors, wherein the detector is connected intermediate the plurality of circuit ends, a circuit driver connected to the plurality of circuit ends so that the circuit forms a loop circuit, the circuit driver controlling one or more power sources to selectively provide power to the first circuit end and the second circuit end, and the detector has a short isolator switch that, when opened, breaks electrical continuity downstream of the detector, wherein the detector scans for a short at startup by receiving power, closing the switch, measuring one or more circuit parameters, and determining whether there is a short based on the one or more parameters.

A fire detection system may include isolation circuit having an isolation switch coupled with a system line of the fire detection system and configured to isolate a first side of the system line from a second side of the system line. The isolation circuit may also include a controller coupled with the isolation switch. The controller may be configured to detect repetitive, intermittent short circuit activity on the system line and control the isolation switch based on this activity.

The invention relates to a computer program product for configuration of a control center, in particular a fire alarm and/or extinguishing control center, and to an associated method. The computer program product comprises: a hardware configuration component for configuration of hardware components such as modules and/or front panel components of the control center, a logic configuration component for configuration of a functional logic of the control center, wherein the logic configuration component is designed to provide functional components. The functional components are decoupled from the hardware of the control center and embodied in such a way that reversible assignment of functional component to hardware component is made possible.

Devices, systems, and methods for an alarming system for multi-unit buildings are described herein. One system includes a number of remote sensors positioned in a building having common areas and individual units occupied by occupants, the remote sensors are provided for sensing an alarm condition, a central control panel located in the common areas of the building for collecting data from the remote sensors, the control panel utilized for analyzing the collected data, determining whether to initiate an alarm, and sending one or more signals to initiate an alarm, if an alarm is to be initiated, and an occupant input device located in at least one individual unit for requesting a delay in initiating the alarm.

Aspects of the present disclosure provide non-addressable detection and alarm systems and methods for controlling a combined circuit by a control panel. In an example, a combined circuit may include paired wires, one or more initiating devices, and one or more notification appliances communicatively coupled with the paired wires in parallel. The control panel may monitor the one or more initiating devices in a standby mode while maintaining the one or more notification appliances in an off state. When the control panel detects an anomaly from one or more initiating devices, the control panel may switch the combined circuit to an alarm mode. In the alarm mode, the control panel may activate the one or more notification appliances and maintain the one or more initiating devices in an off state.

Disclosed is a hazard detector connected to a circuit that has: a plurality of circuit ends and a plurality of detectors, wherein the detector is connected intermediate the plurality of circuit ends, a circuit driver connected to the plurality of circuit ends so that the circuit forms a loop circuit, the circuit driver controlling one or more power sources to selectively provide power to the first circuit end and the second circuit end, and the detector has a short isolator switch that, when opened, breaks electrical continuity downstream of the detector, wherein the detector scans for a short at startup by receiving power, closing the switch, measuring one or more circuit parameters, and determining whether there is a short based on the one or more parameters.