15073 OWNER’S MANUAL
447179 Issue 1 Rev. A
45
9.
9. GLOSSARY
GLOSSARY
Alarm Signal
. A signal indicating an emergency requiring immediate action, such as an alarm for fire
from a manual station, a waterflow alarm, or an automatic smoke detector.
Alarm System
. A combination of compatible initiating devices, control units, and notification appliances
designed and installed to produce an alarm signal in the event of a fire.
Audible Signal
. An audible signal is a sound made by one or more audible notification appliances, such
as bells or horns, in response to the operation of an initiating device.
Authority Having Jurisdiction (AHJ)
. The organization, office, or individual responsible for approving
equipment, installation or procedure.
Class A Circuit
. An initiating device or notification appliance circuit within which all components remain
fully functional, even though a single open or ground exists in the circuit.
Class B Circuit
. An initiating device or notification appliance circuit within which some or all components
may be disabled with a single open or ground exists in the circuit.
End Of Line (EOL)
. A device used to terminate a supervised circuit.
General Alarm
. A term usually applied to the simultaneous operation of all the notification appliances on
a system.
Ground Fault
. A trouble condition in which a low resistance has been detected between the system
wiring and conduit ground.
Initiating Device Circuit (IDC)
. A circuit to which initiating devices are connected.
Labeled
. Equipment or materials to which have been attached a label, symbol, or other identifying mark
of an organization acceptable to the authority having jurisdiction and concerned with product evaluation,
that maintains periodic inspection of the production of such labeled equipment or materials. And by
whose labeling the manufacturer indicates compliance with appropriate standards or performance in a
specified manner.
Listed
. Equipment or materials included in a list published by an organization acceptable to the authority
having jurisdiction and concerned with product evaluation, that maintains periodic inspection of production
of listed equipment or materials. And whose listing states either that the equipment or material meets
appropriate standards or has been tested and found suitable for use in a specified manner.
NEC
. National Electrical Code also published as NFPA standard 70.
Notification Appliance
. An electrically operated appliance used to indicate the system status such as a
bell, horn, strobe light or speaker.
Notification Appliance Circuit (NAC)
. A circuit to which notification appliances are connected.
Power Supply
. That portion of the fire alarm control unit, which provides the power needed to operate all
control unit modules, as well as that, needed to operate all electrically powered initiating devices and all
notification appliances.
Trouble Signal
. An audible signal indicating trouble of any nature, such as a circuit break or ground,
occurring in the device or wiring associated with a fire alarm signal.
Zone
. A designated area of a building. Commonly, zone, is interchanged with initiating device circuit.
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