Access control is a system which enables an authority to control access to an automatic electric gate or pedestrian gate in a given residence, commercial, or government facility. This is accomplished in many different ways – code access on a basic keypad, telephone intercom access, video entry systems, remote transmitter access from a car, biometric readers, proximity readers, emergency gate openers, or bluetooth enabling access from a cellular phone.
KeypadsThis type of device has a numbered keypad and users must input a numbered code. The code is read by the keypad and if one of acceptable codes, sends a signal to the gate operator to open. Some of these keypads can hold hundreds of codes and can have hold-open codes which hold the gate open – useful for parties or when you expect a visitor. Set up anchor here for Keypads on equipment page
Telephone Entry Systems
Some homeowners prefer to have voice interaction with visitors to grant or deny access. Telephone or intercom systems provide for this and some include video cameras to display visitors and even send the signal to a recording device.
Just like garage door remotes, gate opener devices use remotes as access devices. A receiver, usually installed inside the gate operator, receives the signal from the remote when you press the button and sends a signal to open the gate. Liftmaster, Multicode, Linear, and Genie are some of the major brand names in this area.
Emergency Gate Openers
Emergency response personnel need to get access through a gate if there is an emergency. In California, owners of automatic gate systems are required to have a device to allow for this. A knox emergency fire switch from Knox co. allows access for fire or police personnel, depending on the fire switch. A product from Click2Enter allows emergency response personnel to press the button on their two-way radio to gain access to a barrier gate system.
Video cameras for closed circuit TV (CCTV) or to view over the internet can be installed as part of an electric gate system installation. Cameras – sometimes called bullet cameras – with infrared technology for night vision or the ability to read license plates can be installed in trees, on fences or on columns. Pin-hole cameras can be hidden in telephone or intercom keypads. The video signal should be run back to the house or facility using a special co-ax cable or using a phone wire (gel-filled for extra durability). Co-ax can be used for distances under 500 ft. From 500 ft. to 1000 ft., phone cable can be used with a non-powered balun on either end. Powered baluns are required on both ends for distances over 1000 ft. Read more about Baluns.
Proximity Cards and FOBs
Proximity card devices consist of two components: a card reader and special cards attuned to specific transmission codes. The reader uses an antenna coil to send signals to the cards which receives the reader’s signal with its own antenna coil and reflects the signal back to the reader with its unique code . The reader may then verify or deny verification of the card’s code. Some Telephone Intercom Systems connect to the proximity detector as a Wiegand device and are configured to read the codes from the prox card reader and verify them from their own database.
A device that utilizes a pre-issued card which the holder inserts or swipes on the reader. The card contains the code which the reader may verify or reject. Similarly, these readers can be used as modular add-ons to many Telephone Entry systems. HID is a popular manufacturer of these cards and devices.
Electric strikes are an access control device used for doors or pedestrian gates. An electric strike’s ramped surface can, upon command, pivot out of the way of the latch allowing the door to be pushed open (from the outside) without the latch being retracted. A knob or lever can still be turned to allow exiting from the secured area. Electric strikes can be fail safe for fail secure. Fail safe means that the strike is active when power is on but inactive when power goes out. Fail secure means that the strike is active when energized and locked when power goes out. Von Duprin and HES are two manufacturers of electric strikes.
Photos of telephone intercom systems and keypads installed