Simplex 4100U Application Manual page 95

Glossary of Terms,
Glossary
Continued
Ground Fault – A condition in which the resistance between a conductor and ground reaches an
unacceptably low level.
Heat Detector – A device which detects abnormally high temperature or rate-of-temperature rise.
Horns – An audible signal appliance in which energy produces a sound by imparting motion to a
flexible component that vibrates at some nominal frequency.
HVAC system – Heating, ventilation, and air conditioning system.
IDC – Initiating Device Circuit.
Initiating Device – A manually or automatically operated device, the normal intended operation
of which results in a fire alarm or supervisory signal indication from the control unit. Examples of
alarm signal initiating devices are thermostats, manual boxes, smoke detectors, and waterflow
switches. Examples of supervisory signal initiating devices are water level indicators, sprinkler-
system valve-position switches, pressure supervisory transmitters, and water temperature switches.
Initiating Device Circuit – A circuit to which automatic or manual signal initiating devices such
as fire alarm boxes, fire detectors, and waterflow alarm devices are connected.
Labeled – Equipment or materials to which has 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 production of labeled equipment or
materials and by whose labeling the manufacturer indicates compliance with appropriate standards
or performance in a specified manner.
Leg Facility – That part of a signaling line circuit connecting each protected building to the trunk
facility or directly to the central supervising station.
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 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.
Local Alarm System – A local system sounding an alarm as the result of the manual operation of
a fire alarm box or the operation of protection equipment or systems, such as water flowing in a
sprinkler system, the discharge of carbon dioxide, the detection of smoke, or the detection of heat.
Local Energy Auxiliary Alarm System – An auxiliary alarm system that employs a locally
complete arrangement of parts, initiating devices, relays, power supply, and associated
components to automatically trip a municipal transmitter or master box over electric circuits that
are electrically isolated from the municipal system circuits.
Local Supervisory System – A local system arranged to supervise the performance of guard
tours, or the operative condition of automatic sprinkler systems or other systems for the protection
of life and property against the fire hazard.
Local System – A local system is one that produces a signal at the premises protected.
Maintenance – Repair service, indicating periodic inspections and tests, required to keep the
protective signaling system and its component parts in an operative condition at all times, together
with replacement of the system of its components, when for any reason they become
undependable of inoperative.
6-5
Continued on next page