Search results
Results From The WOW.Com Content Network
A simple electromagnetic door holder consists of a strong electromagnet, usually attached to a wall or mounted in a floor pedestal enclosure, next to the door it controls. The mechanism may be mounted near the floor, at the upper corner of the open door, or at any convenient height along the latch edge (away from the hinged edge).
Electronic article surveillance antennas at an H&M store in Torp shopping mall, Sweden. Electronic article surveillance (EAS) is a type of system used to prevent shoplifting [1] from retail stores, pilferage of books from libraries, or unwanted removal of properties from office buildings.
Examples are door and window sensors in burglar alarm systems and tamperproofing methods. Reed switches have been used in laptops to put the laptop into sleep/hibernation mode when the lid is closed. Speed sensors on bicycle wheels frequently use a reed switch to actuate briefly each time a magnet on the wheel passes the sensor.
Many exit control locks are based on magnetic locks. One type, delayed egress magnetic locks, will not allow the door to open immediately. This allows a guard to get to the door before the door opens. It will also release if there is a fire alarm or power failure, but otherwise these locks hold the exit doors shut. These units are common in ...
Door and window sensors are also implemented in most home security systems. One part of the system is installed on the door or window itself while the other part is installed on the frame of the door or window. The two part system connects securely when a door or window is closed, creating a security circuit. [5]
Sensors: In a security alarm, some sensors detect intrusions. Sensors' locations are at the perimeter of the protected area, within it, or both. Sensors can detect intruders by different methods. Alerting devices indicate an alarm condition. Most commonly, these are bells, sirens, also and or flashing lights. Alerting devices serve the dual ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
A metal doorframe with a strike plate built in: in other doors this would be a metal strikeplate in a wooden doorframe. The term door security or door security gate may refer to any of a range of measures used to strengthen doors against door breaching, ram-raiding and lock picking, and prevent crimes such as burglary and home invasions.