NICET FAS-IV key terms

A field component with its own unique digital identifier on a signaling line circuit, allowing the panel to report and control it individually rather than as part of a zone.

The addressable loop or branch wiring that carries digital communication between the control unit and individual addressable devices; also called the data circuit.

The conventional circuit wiring that connects automatic detectors and manual pull stations to the control unit so it can detect an alarm condition on that circuit.

The circuit that powers and supervises audible and visible signaling appliances such as horns, speakers, and strobes, typically requiring end-of-line supervision and adequate power.

A fire alarm arrangement in which devices are wired to circuits that the panel monitors as groups, so the panel identifies the circuit rather than the individual device in alarm.

A defined area or grouping of devices that the system annunciates as a single location, used for alarm identification, and in some arrangements for detection or suppression release logic.

The repeated interrogation by the control unit of each addressable device on a signaling line circuit to collect status and verify that the device is still communicating.

Continuous monitoring of circuit integrity so that opens, shorts, or ground faults in wiring are detected and annunciated as trouble rather than remaining hidden until a fire occurs.

A circuit wired so that an open or single ground fault does not prevent operation of devices beyond the fault, because the path returns to the control unit.

A circuit wired as a single path that returns through an end-of-line device; an open stops supervision and operation of devices beyond the break, and the panel annunciates a trouble.

A resistor installed at the far end of a supervised conventional circuit that permits the panel to detect opens and, with the correct value, distinguish alarm current from normal standby current.

A device on an addressable loop that opens the circuit on both sides of a short circuit so the remainder of the loop can continue to communicate with the control unit.

A distinctive audible and visible indication that a fault exists in the system, such as an open circuit, ground fault, or loss of primary power, requiring timely attention by responsible personnel.

A signal indicating that a system or suppression component has changed to an off-normal condition, such as a closed valve or low water level, that could impair protection if not corrected.

The signal produced by the system when an initiating device operates, causing notification appliances to sound and the alarm to be displayed at the control unit and annunciators.

A remote display unit that shows alarm, supervisory, and trouble conditions by zone or device label, commonly installed at a main entrance or other location staffed by responders.

An automatic device that senses products of combustion, using ionization, photoelectric, or other principles, and signals the control unit when smoke reaches its threshold.

A smoke detector installed in an air-handling duct that samples airflow to detect smoke moving through the HVAC system and typically initiates shutdown of the unit it serves.

The maximum listed distance between detectors and from walls or obstructions, adjusted for ceiling height and configuration, used to lay out coverage that meets the applicable installation standard.

An automatic device that responds to a fixed temperature threshold, a rate of temperature rise, or both, commonly used where smoke detection would be unsuitable or prone to nuisance alarms.

A manually operated initiating device, typically located along exit paths, that a person actuates to transmit an alarm signal to the control unit.

A device that senses movement of water in a sprinkler system and sends an alarm signal, usually after a delay, to indicate that a sprinkler head or other device has operated.

A monitoring device that reports when a valve or other suppression component is moved from its normal position, producing a supervisory signal at the control unit.

An arrangement that delays notification appliance activation for a limited period while trained staff investigate, provided the alarm is acknowledged within the allowed time; otherwise notification proceeds automatically.

A detection arrangement in which two or more zones must both report alarm before the system takes a programmed action, reducing false alarms from a single detector.

Coordination of flash timing among visible notification appliances in the same field of view so that the combined flashing does not create a hazard for people with photosensitive conditions.

The reduction in voltage along notification appliance circuit wiring caused by current flowing through conductor resistance, which must be calculated to ensure appliances operate within their listed range.

The ability of critical fire alarm circuits to continue functioning during a fire, achieved through circuit path protection, separation, or other measures required for the system's performance category.

An emergency communication arrangement that delivers prerecorded or live voice messages over speakers to direct occupants, often combined with visible appliances and selectable message zones.

A system that delivers emergency information to a large population inside or outside a building using voice, text, or other means, often integrated with the fire alarm control unit.

The central component that receives signals from initiating devices, processes them according to its program, controls notification appliances, and displays system status.

A display panel installed away from the control unit, connected by a supervised data path, that repeats alarm, supervisory, and trouble indications for use by responding personnel.

The engineering computation of standby and alarm current loads to size backup batteries so the system remains operable for the required standby period plus alarm duration.

An unintended connection between a circuit conductor and earth or enclosure, detected by the control unit and reported as a trouble condition requiring correction.

A feature that requires a detector to remain in alarm for a set interval or to confirm on a second sample before the system processes the signal, reducing nuisance alarms.

A planned exercise that activates notification appliances to practice evacuation or response procedures, often initiated from the control unit without an actual fire condition.

A document prepared at installation that records the system's configuration, devices, and verification results, and is updated when the system is modified.

A visual and functional check of system components to confirm they are in place, undamaged, and unobstructed, performed at the intervals required by the applicable code.

Operation of system components to confirm they perform their intended function, conducted at required intervals and documented, with results compared against the design and record of completion.