1+n (AKA Simplified Audio)
1+n systems require 1 cores of cable + the number of handsets on the system. For example a 3 way system would require 4 cores (1+3).

4+n (AKA 5 wire Audio)
4+n systems require 4 cores of cable + the number of handsets on the system. For example a 3 way system would require 7 cores (4+3).

Access Control System
A generic term used to describe a system for controlling access through a door (gate, shutter or whatever) using (generally) electronic or electro-mechanical system.  Example include keypad access control, card reader access control.

Battery Backup
Battery backup on a door entry or access control system allows the system to continue to function in the event of power failure. This is achieved by connecting a rechargeable battery to the PSU which begins to power the system in the event of the primary power source failing.

Category 5 (Cat 5) is a twisted 4 pair cable for carrying signals. This type of cable is used in structured cabling for computer networks such as Ethernet. It is used in door entry systems to carry audio and video signals.

Digital call
Digital call allows a call to be made from a door entry panel by entering a number on a keypad or scrolling through a selection of options. This is particularly common on systems with a large number of apartments as it takes up less space than having a high number of functional call buttons on a panel.

Electric Strike
(see lock release)

This is actually a brand name, but quite often used in place of Door Entry System

Entry panel
An entry panel is the part of a door entry system from which a call is initiated. The entry panel usually has a speaker and microphone to allow communication between the panel and the internal handsets or monitors.

Fail Locked
See fail secure.

Fail Safe
Fail safe in terms of electric locking is a device that will release when a system malfunctions or power is taken away from it. An example of this would be a magnetic lock.

Fail Secure
A fail secure electric lock is one that will remain locked in the event of a power failure.

Fail Unlocked
See fail safe.

Functional panel
A functional panel is an entrance panel which has call buttons individually assigned to one apartment.

Gate lock
(see lock release)
Gate locks on electric gates are generally fitted surface mount and are 12 Volts AC operation (see Cisa locks for some examples)

Intercom System
(see door entry system)

Intercom (between phones – global and individual)
Intercom allows different handsets or monitors on a system to communicate between each other independently of the front panel. Global intercom only allows users to call every user on the system. Individual intercom allows users to select who they want to call individually.

Mag Lock
(see Magnetic Lock)

Magnetic Lock
Magnetic locks are Fail Unlocked devices used to secure a door (or gate using an external type).  They require DC power continuously and generally draw about 500mA.  I wide range are available in various sizes.

Mortise Strike (flush mount)
As Electric strike, but fits flush into the door frame.  Usually compatible with mortise night latch locks (eg Union 2332 or similar locks)

Latch Release
(see lock release) Mortise or surface mount versions are available in various finishes.

Lock Release
A Lock release (or electric strike) is a device which release the bolt of a lock (fitted to a door) by applying power (in the case of Fail Locked devices) to the device.

A power supply unit (PSU) is a device that supplies electrical energy to one or more electrical loads.

Proximity Card (AKA Prox Card)
Proximity Access Control requires the user to have some form of identification.  Usually this is a card, or key ring type tag (AKA Fob, Token).  There are generally 2 types of card, both credit card sized, but varying in thickness.  ISO cards are 0.8mm thick whereas clam shell cards are from 1.8mm thick and sometimes much thicker.  ISO cards are often printer compatible, meaning they can be over printed with a suitable Dye Sublimation printer.

Rim Strike (surface mount)
(see lock release)
As Electric strike, but fits surface onto the door frame.  Usually compatible with Rim night latch locks (eg Yale 89DMG or similar locks)

(see lock release)

Stand Alone
Normally referring to an access control system where the control is built into the access control reader (or keypad)

Tag (or token)
Proximity Access Control requires the user to have some form of identification.  Usually this is a card, or key ring type tag (AKA Fob, Token)

VR (or Vandal Resistant)
Many door entry panels are referred to as Vandal Resistant.  Generally this means the front plate is 2.5mm thick stainless steel, with robust anti vantal push buttons and protection against vandalism of speaker unit and camera (if fitted).  In general many DDA panels are also vandal resistant.