Glossary

Click on letter to skip to industry terms

• 0-9
• A
• B
• C
• D
• E
• F
• G
• I
• J
• L
• M
• N
• P
• R
• S
• T
• U
• V
• W
• Z

Index

Terms starting with "0-9"

24-hour Sensors

Those system sensors which cannot be disarmed or bypassed, such as fire, moisture and smoke detectors.

Terms starting with "A"

Access Codes

A keypad-entered numeric combination to gain access to the system.

Access Control

Computerized and mechanical processes based on users' identities and predefined roles for controlling access to protected facilities. Can be integrated with intrusion, fire detection and access control.

Alarm

A device for signaling an emergency condition.

Antenna

A transmitting device to convert radio frequency energy into an electromagnetic field that travels through space, or a receiving device that converts an electromagnetic field in space into RF energy that can travel via a wire or cable.

Anti-Passback

An access control feature to prevent system users from sharing their access codes or cards with someone else. A user code must be used to enter and then to exit before it can be used to enter again. Similarly, to prevent the same PIN from being used by several persons, a time delay can be programmed so the PIN won't work again until the time delay is complete.

Arming

Activation of the security system to enable its sensors detect changes of state and report those changes to the control panel.

Arming Levels

A set of instructions which determines those sensors to be activated and those which are not. All sensors are armed when you are away from home, for example, but interior motion sensors would not be when you are home and moving around the house.

Asset Tracking

Software to enable control of physical assets, such as laptop computers and other high-value equipment. The system ensures that the cardholder requesting access is authorized to take assets through designated alarm points.

Auxiliary/Medical Alert and Alarm

An alarm signaling the need for medical personnel.

Terms starting with "B"

Backward-Compatible

Equipment that can operate with earlier and future versions of software. Backward-compatible products enable innovation without additional equipment upgrade costs.

Band

The frequencies used for a specific class of RF wireless communications system.

Bandwidth

The amount of radio spectrum used by a communications system. Both the transmitter and the receiver have a measurable bandwidth (measured in Hertz). A receiver's bandwidth must be as large or larger than the transmitters bandwidth, so that all of the signal is received.

Biometrics

Usually used as part of an access control system, biometrics identify individuals on the basis of fingerprints, iris patterns, or other identifying traits.

Bypass

An instruction to a security system not to arm a specific sensor.

Terms starting with "C"

Carbon Monoxide

A colorless, odorless, and highly toxic gas produced during combustion by furnaces, water heaters, and other home appliances. According to the National Safety Council and the Center for Disease Control, 5,000 people in the United States are treated in emergency rooms for carbon monoxide poisoning and CO kills between 500 and 1000 persons each year in their homes.

CCTV

Closed-Circuit Television. The use of cameras for surveillance. Images may be viewed on a monitor, via the internet, or digitally recorded for later viewing and submission as evidence.

Central Monitoring Station

a facility that receives alarms from subscribers' security systems and requests the dispatch of fire, police, or medical authorities.

Control Panel (system controller)

the "brains" of the security system. Receives transmissions from sensors and communicates data to the central monitoring station.

Terms starting with "D"

Decibel

a measure of the relative difference between the power level of two signals. The signal strength of a door/window sensor in a residential system might range from .1mW for a close-in transmitter to .00000000001mW for a transmitter in a remote closet.

Delay

the time allotted the system user to exit the premises after turning the system on without causing an alarm (exit delay); the time allotted the system user to enter the premises and turn off the system without causes a false alarm (entry delay).

Disarm

to turn the system or a sensor off.

Diversity

to eliminate the effects of multipath distortion, diversity communications systems use redundant signal paths between the transmitter and receiver.

Door/Window Sensor

a device for detecting the opening of a door or window and for sending a signal to the control panel indicating the change of state.

DVMR

Digital Video Multplexer/Recorder. A device that receives images from several CCTV cameras at once and enables the images to be viewed on a monitor or recorded.

Terms starting with "E"

Electric Strike

Electronic device for locking and unlocking doors in response to signals from an access control system.

Electronic Access Control

Controlling entry into a physical area by means of a controller and electronic components including locks, readers, sensors, buttons and more. Electronic access control specifies who can go where and when.

Ethernet

A way of networking multiple devices into one system, enabling a security system to be controlled from different access points within the network.

Event Log

A record of actions performed and recorded by a security or access control system.

Terms starting with "F"

False Alarm

any alarm sounded when there is no cause for alarm.

Fire Alarm

a signal transmitted by heat or smoke detectors and Pull Stations.

Free Air Range

the line-of-sight unobstructed communications distance of a transmitter/receiver system.

Terms starting with "G"

Glassbreak Sensor

a device that detects frequencies that accompany the breaking of glass

Terms starting with "I"

Interference

RF energy in the receiver's band which is not made by a system transmitter; reduces the communications range of a transmitter-receiver system.

Interior Sensors

devices that register changes of state of interior spaces or doors.

Intrusion Alarm

a signal transmitted by sensors that detect intrusion. Door/Window sensors and motion sensors most commonly send intrusion alarm signals.

Terms starting with "J"

Joystick

A controller for moving a pan/tilt/zoom camera up, down, left or right.

Terms starting with "L"

Local Area Network (LAN)

A connected system of cameras, recorders, and other security systems that communicate with each other and can be controlled from different access points in the system.

Terms starting with "M"

Message or Data

the information sent by a communications system.

Module

in home automation, a device for interfacing controllers with security devices, lamps, appliances, and other devices. Each module has an address which may be unique or may be the same as other modules.

Monitoring Service

see Central Monitoring Station

Motion Detector

Passive Infrared: PIR: An intrusion detector designed to register changes of temperature, which occur when an intruder enters a protected space.

Terms starting with "N"

Narrow Band

refers to a communications system that transmits and receives using only as much radio spectrum as is needed to pass the message data rate.

No Delay

with remote arming and disarming capabilities the system user can approach the premises and before entering disarm the system with no delay. This eliminates the feeling of being rushed to turn off the system to prevent a false alarm after entering a delay door.

Terms starting with "P"

Panic Button

a remote control device or a button on a control panel that sends an alarm signal without requiring the use of an access code.

Panic Pendant

a portable device that sends a wireless panel signal to the control panel. They can be worn around the neck with a neck strap, clipped to a belt, or placed in wall-mounted holders.

Terms starting with "R"

Radio Frequency

the alternating voltage and magnetic fields in a radio signal. Frequency is measured in cycles per second, which is usually referred to as a Hertz after the man who discovered them. A megaHertz (MHz) is a frequency of 1 million cycles per second.

Radio Spectrum

the frequency range of electromagnetic radiation used for all RF wireless communications systems.

Receiver sensitivity

the ability of the receiver to hear the transmitter's signal.

Receiver

the RF analog and logic components in the security alarm panel that processes the signals received by the antenna and reconstructs the digital message of the transmitter.

Terms starting with "S"

Sensor

a device that detects a change from one state to another. For example, a door/window sensor detects the change in a circuit from a normally closed state to an opened state.

Silent Alarm

an alarm received by a central station operator which does not activate a local alarm sound.

Smoke Sensor

a device of either photoelectric or ionization design which detects the presence of smoke and sends a fire alarm signal to the control panel.

Spatial Diversity

using two or more antennas (on either the transmitter or the receiver) where the two antennas are switched. Having antennas with unique locations provides independent signal paths through space and thereby significant fade resistance.

Supervision

the use of a special signal sent automatically from the transmitter to the receiver to inform the receiver that the transmitter is operating properly.

Terms starting with "T"

Transmitter Power

the intensity of the transmitter’s signal. The higher the power radiated by the transmitter's antenna the greater the reliability of the communications system.

Transmitter

the circuit that includes logic that generates a baseband message describing the status of the inputs to the transmitter, a radio frequency oscillator that generates the carrier frequency, modulation method to impose the message onto the carrier frequency, and an antenna to radiate the signal.

Two-Way Voice

a technology for allowing a central station operator to hear what transpires after an alarm is activated and to talk to persons on the scene.

Terms starting with "U"

User ID

A unique identification code that enables access. Usually used in conjunction with a password.

Terms starting with "V"

Video Motion Detection

Detection and triggering of video recording by a camera

Terms starting with "W"

Wave Length

the distance that the radio wave travels in one cycle of the transmitters frequency. At 300 MHz a wavelength is about 30 inches and at 900 MHz a wavelength is about 8 inches.

Wireless Keychain Touchpad

a system-controlling device designed to fit in a pocket or purse

Terms starting with "Z"

Zone

sensor or group of sensors having a single numerical identity.