Access Code – A four-digit (usually) code that allows a user to turn an alarm system on (Arm) or off (Disarm.)
Alarm System – Also called a security system, a group of interconnected components which monitors the condition of a home or other building.
Arm – To turn the security system on. Most of today’s controls will not allow the system to be armed unless all zones are secure.
AWG – American Wire Gauge is the means for measuring wire diameter. Larger numbers represent smaller diameter wire, and vice versa. A cable is usually described by its AWG size followed by the number of wires (conductors) it contains. For example, a cable listed as 22-4 is a four-conductor cable made up of four wires, each 22 gauge.
B Connector – A small insulated connector used to join and insulate two or more wires at a splice. The stripped ends of the wires are placed inside the connector, and it is crimped with pliers or (preferably) a crimping tool. The connectors are often call “beanies” or “chicklets” by installers.
Backup Battery – Another term for Standby Battery.
Bell – Industry term for the sounding device, usually a siren, that loudly announces that the system is in alarm. Decades ago, the device was usually a large bell mounted on the outside of a building. Although these are seldom used now, the term has endured.
Bell Cutoff – The amount of time before an alarm system’s siren (or bell) stops sounding after an alarm takes place.
Bypass – To deactivate a zone or zones before arming the system. For example, the user might want to arm the system while leaving the back door open while he/she works in the back yard. The back door would be bypassed at the keypad before arming the system.
Can – Installer jargon for the enclosure that houses the control unit.
Central Station – An agency that monitors alarm systems and contacts local authorities if an incident occurs. Most often, an alarm system communicates with the central station by telephone.
Chime – A sound that keypads can be programmed to emit when a zone is opened or closed. The opening of a front door, for example, might cause the keypad to chime. This is used when the system is NOT armed.
Communicator – The element on an alarm control that automatically dials a central station and relays information about the protected building. It communicates digitally with the central station computer; it cannot produce spoken words that could be understood by a human.
Contacts – Industry term for the switches that are mounted at doors and windows to inform the control panel of openings and closings.
Control Panel – An enclosure containing an alarm system’s main circuit board, a backup battery, and possibly other components necessary for the control of the system. It is NOT the Keypad, although in some wireless systems, the keypad is mounted directly on the control panel.
CS – Central Station
Default – The factory-set value for any programmable option in the alarm system. To “default the system” is to perform either a hardware or software operation that returns ALL options in the system to values they had when the system left the factory.
Disarm – To turn the security system off.
End-of-Line Resistor – A resistor placed in an alarm circuit, allowing the control panel to “supervise” the circuit (make sure that everything in that circuit is intact.)
Entry Delay – The amount of time before an alarm occurs after a triggering event. For example, if a door opens while a system is armed, a warning will sound for a pre-set number of seconds before the siren sounds or the control panel calls the central station.
Exit Delay – The amount of time between the moment a system is turned on (armed) and the moment it becomes active. During that period, triggering a detection device (opening a door, moving in front of a motion sensor, etc.) will NOT cause an alarm.
Hardwired – A method of installing an alarm system where all of the components are connected to the control panel by wires.
Heat – A heat detector, a sensor that triggers an alarm if the temperature in a room rises at an unusually rapid rate or reaches a pre-set heat limit, or both. It does not detect smoke, although some smoke detectors have heat sensors built in to their circuitry.
Hybrid System – An alarm system that is capable of using both hardwired and wireless communication between components and a control panel.
Keybus – A set of four connections on an alarm system that allows other digital devices to communicate with it. Keypads and expansion modules are among the devices that would be connected to these same four terminals.
Keypad – A device that allows a user to control an alarm system by pressing keys numbered 1 through 0. In addition to the keys, almost all keypads have some means of displaying information to the user about the system. The keypad is NOT the Control Panel, although in some wireless systems, the keypad is mounted directly on the control panel.
LAHJ – Local Authority Having Jurisdiction
Line Seizure – An alarm system feature that allows the system to take complete control of the house telephone system in the event of an alarm. This would prevent, for example, an intruder from disabling the alarm system phone dialer by picking up an extension phone.
Loop – A term sometimes used for the wiring circuit in a zone. A zone might have five switches forming one continuous loop.
Master Code -- A four-digit (usually) code that allows the primary user of an alarm system to turn the system on (Arm) or off (Disarm) as well as make limited changes to the system (for example: adding, changing, or deleting access codes.)
Memory – If an alarm has occurred, the alarm system will retain it in its memory and display it on command, so that the user can know what caused the alarm.
Normally Closed – A type of alarm system wiring in which a detection device has a switch or circuit that is closed when the door or window is closed (its “normal” condition).
Normally Open -- A type of alarm system wiring in which a detection device has a switch or circuit that is open when the device is secure (its “normal” condition).
Partition – A means of dividing an alarm system into two or more independent subsystems. For example, one system could serve two apartments, with certain zones assigned to one apartment, certain zones assigned to the other, and some zones (like a common hallway) assigned to both. Each partition would have its own keypad for independent control.
PIR -- “Passive Infrared”, the most common type of motion detector. It is passive because it does not emit any type of energy, but rather senses the movement of body heat through the zones into which it divides the coverage area.
Programming – In an alarm system, setting the numerous options that will determine exactly how the system will operate.
Resistor – A small semiconductor that reduces the amount of current flowing through a circuit.
RJ31X – A special telephone jack that allows a user to disconnect the house telephone system from the alarm panel in case it malfunctions. This is only needed in systems with central station monitoring.
Smoke – A smoke detector that is connected to an alarm system control panel. Some system smoke detectors also include Heat detectors that trigger an alarm if the temperature in a room rises at an unusually rapid rate or reaches a pre-set heat limit, or both.
Standby Battery – A rechargeable battery, normally in the control enclosure, that provides power to the system in the event that AC power is removed. It also can deliver extra current if need during an alarm situation (to help power the sirens, for example). It is sometimes referred to as the Backup Battery.
Supervision – A configuration that allows an alarm system control panel to make sure that other components of the system are intact.
Wireless – A method of installing an alarm system, where all or most of the components communicate with the control panel by transmitting radio signals.
Zone – A protected area of a building, as seen by the alarm system. A zone might include a door, one or more windows, a motion detector, or any detection device that is monitored by the control panel, alone or in a group.