Glossary: Access Control

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4/6 core security cable (7/0.20and 14/0.20) 4 or 6 conductors. 7 and 14 stands for the number of copper strands in each core .20 is the diameter of each strand.
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Alternating current (AC) An electric current that reverses its direction regularly and continually. The voltage alternates its polarity and direction at current flow negative to positive. AC current.
   
Ampere (amp) The unit of measurement for the rate of electrical current flow characterized by the symbols l (in Ohm’s law formulas) or A. One ampere is the current flowing through one ohm of resistance at one volt potential.
   
Annunciator An audible and visual signalling device.
   
Anti-passback A means of preventing the sharing of an access control credential. Anti-passback can be based upon disabling a credential for a period of time after it is used, or by remembering the credential-holder’s in/out status.
   
Audit trail A means of recording and saving access control event history for later review.
   
Ausi Duct Ducting is used to protect concealed cabling.
   
Authorized release device  A device that when activated allows authorized persons to enter or exit monitored and controlled openings without triggering an alarm. The authorized released may be a keyed switch, a card reader, a digital code reader and so forth.
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Badge, Badging Use of a card for identification purposes. Cards used to unlock doors may sometimes be printed to serve also as I D. badges. The term can also refer to the act of using a credential on a reader to gain access.
   
Battery standby  A means of automatically switching over to stored battery power during local primary power failure.
   
Biometrics  The measurement of a physical trait that is unique, such as a fingerprint, hand geometry or iris pattern. In access control this is used to identify authorized users and to grant or deny access.
   
Break To open an electrical circuit.
   
Brownout  Low line voltage that can cause miss-operation of and possible damage to equipment. For example a motor that tries to start at low voltage can actually be in a lock-rotor condition and can overheat.
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CAT5 A very common cable type that consists of several twisted pairs in an overall protective jacket. Used for network cabling and many access control data functions.
   
Circuit  The path through which electrical energy flows.
   
Circuit, closed  (1) An electrical circuit in which current normally flows until interrupted by opening of a switch-type electronic component. (2) A circuit or switch in which the contacts are open during normal operations.
   
Circuit, open  (1) An electrical circuit in which current does not flow until permitted by the opening of a switch or a switch-type electronic component. (2) A circuit or switch in which the contacts are closed during normal operations.
   
Clock and Data A type of data transfer format used by different readers.
   
Closure  The point at which two contacts meet to complete a circuit.
   
Conduit  A tube or trough for protecting wires and cables. It may be a solid or flexible tube in which insulated electrical wires are run.
   
Conduit (Grey) Plastic tubing used to protect and conceal cabling. (used above ground and under ground for low voltage.)
   
Conduit (Steel) Steel conduit used to protect and conceal cabling. (Used commonly in fire Stairs.)
   
Controller, Control Panel  A circuit board or group of circuit boards that contain programming for the operation of an access control or other system.
   
Credential Anything that is used to badge a reader. A card or fob for example.
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Decibel (dB)  An increment of measurement used to compare measured levels of sound energy (intensity) to the apparent level detected by the human ear, expressed as a logarithmic ratio.
   
Delay  A period of time before or during an event.
   
Delay on break  A term used to describe a mode of operation relative to timing devices. The delay begins when the initiate switch is opened (delay break of initiate switch).
   
Delay on energization  A term used to describe operation relative to timing devices. The delay begins when the initiate switch is closed or application of power to the input.
   
Diode  Stops back Electro magnetic interference (EMF) entering controller.
   
Direct current (DC)  Electrical current that travels only in one direction and has negative and positive polarity. It may or may not have an AC ripple component. DC sources that are unfiltered should be referred to as full-wave or half-wave rectified circuits.
   
Distributed Memory An access control system where all the relevant information relating to that controller is stored at the controller. This allows the system to operate even if the computer network is not operational.
   
Door open time  The time that an access control device unlocks an opening for entry, usually programmable. Can sometimes be refered to as a delay.
   
Door status switch (DSS)  A DSS is a switch used to monitor whether a door is in an opened or closed position.
   
Dry contract  Metallic points making (closing) or breaking (opening) a circuit. The switch circuit must have its own source of power and is merely routed through the dry contacts.
   
Dry joint A soldered joint that looks good but has no conductivity
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Egress An egress is simply another word for exit, or a place of exit.
   
Electric Strike  A door unlocking device that is installed in the door jamb and that works in conjunction with a mechanical lock or latch mechanism.
   
Electrified Lock  A mechanical locking device that has been modified to allow an electric circuit to lock or unlock it.
   
Electromagnetic Lock (Magnetic Lock, Mag Lock)  A device that locks/unlocks an opening without moving parts, using pure electro-magnetic attraction.
   
EMF Electro magnetic interference caused by cabling to close to mains power or failing to install diode on the lock.
   
Exit Switch/Sensor/Bar  A type of switch that is designed to facilitate egress through an opening. Usually used with electromagnetic locks, these come in a variety of types.
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Fail Safe When a locking device is unlocked when no power is applied.
   
Fail Secure When a locking device is locked when no power is applied.
   
Figure 8 ( 14/0.20 and 24/0.20) Power cable used for locking devices, power also REX buttons. 14 and 24 stands for the number of copper strands in each core .20 is the dia of each strand
   
Fire Trip Used to interrupt power to a controller/strike when the fire system is activated. Usually installed by the fire system installer and provided to the access system via a single pair of cables.
   
Fuse A protective device, placed in a circuit as a safeguard, that contains a metal. When the current flow becomes too great, the metal melts, thus breaking the circuit.
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Glass break A device mounted near the exit door that can be used to release the door in the event of an emergency.
   
Ground  A conducting connection between an electrical circuit and the earth or other large conducting body to serve as and electrical ground, thus making a complete electrical circuit.
   
Ground, earth  The portion of a circuit that is connected to a buried metallic object such as a grounding rod or water pipe.
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Heat shrink A covering placed over soldered joints to seal them
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Keypad In access control, usually refers to a numeric input device used to identify a user by PIN (personal identification number).
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Light emitting diode (LED)  A diode, a solid-state device, that gives off virtually heatless coloured light when electric current is passed through it. LED’s are very efficient and long lasting and are often used for digital readouts and annunicators. Common colours include red, green, and amber.
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Mag Lock See Electromagnetic Lock.
   
Motherboard  A master printed circuit board used to interface the activities of individual printed circuit boards and the devices being controlled monitored. The motherboard is usually located on the back of a control panel assembly; individual printed circuit boards plug into it.
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N/C & N/O Normally opened circuit and normally closed circuit
   
Normally Closed (NC)  The condition or position of contact prior to initiation or energization, in this case, a closed condition.
   
Normally open (NO) The condition or position of contact prior to initiation or energization, in this case, an open condition.
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Ohm The unit of measurement of resistance.
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Passage mode Most access control systems can be put into passage mode. This means that the usual code (or other means of credential) is not required to open the door.
   
Passive Infrared Detector (PIR) A motion sensing device, often used for intrusion detection systems, can also be used to unlock a door as someone wishing to egress approaches.
   
Piezo A siren or Buzzer.
   
Presco A type of data transfer format used by different readers.
   
Proximity  A common access card technology, proximity uses radio frequency to communicate between a card or tag and a reader without physical contact.
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Reader The device that sends the key or card data to a controller. (Some units combine reader and controller in one device.)
   
Recycle time  The time needed to reset and rein the timing function and remain within the specified timing tolerance. Recycle time is generally specific "during timing" or a "after timing".
   
Relay A switching device to turn power on for a preset time 
   
Remote alarm  A visual or audibly signalling device used to signal violations at locations removed from the central control station or monitored open. For example, a remote alarm may be placed roof, in a stair tower, or at guard station outside a building.
   
Remote reset  A switch located at a monitored opening. If a violation occurs, the alarm at the control console can not be turned off until the?? is secured and the remote reset is activated. Its purpose is to ensure the inspection of an opening that has been violated or left open.
   
REX Request to Exit usually refers to a button to exit
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Saddle A clip to hold conduit to a wall, floor or ceiling
   
Scotch Locks A device to join cables usually used with Cat5 cable
   
Shielded & Unshielded Refers to a covering inside the cable to prevent interference from external power (240/EMF)
   
Shunt  Electrical term for bypassing. In access control it is common to shunt an alarm sensor, such as a door position switch, when a door is about to be opened for valid access or egress.
   
Silkey A type of data transfer format used by different readers.
   
Sirus A type of data transfer format used by different readers.
   
Solenoid An electro-mechanical device that operates the lockbolt. When electricity is applied, a mechanical motion is obtained that moves the bolt.
   
Standalone  This term usually refers to a device that identifies the user (keypad, reader, etc.) and that makes an access decision. Some standalone units also contain a locking device and/or a power source.
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Terminal Block A place to terminate cables 
   
Termination Cables that have been fun to a point and ended
   
Tinned Having the ends of the cable soldered to aid connection
   
Toggle When used in terms of access control, the term toggle refers to changing the default state of an access control system to passage mode (or from passage mode).
   
Transfer Loop A method of transferring power from frame to door
   
Trigger Opening of a device for a predetermined time
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Weigand A type of data transfer format used by different readers.
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Yellow Tongue   Plastic strip for aiding cabling (from yellow tongue flooring)