Security Systems

 

Security Control Panel

A security alarm is a system designed to detect intrusion – unauthorized entry – into a building or area. Security alarms are used in residential, commercial, industrial, and military properties for protection against burglary (theft) or property damage, as well as personal protection against intruders.

  • Alarm Control Panel (ACP), or simply panel: The "brain" of the system, it reads sensor inputs, tracks arm/disarm status, and signals intrusions. In modern systems, this is typically one or more computer circuit boards inside a metal enclosure, along with a power supply.
  • Sensors: Devices which detect intrusions. Sensors may be placed at the perimeter of the protected area, within it, or both. Sensors can detect intruders by a variety of methods, such as monitoring doors and windows for opening, or by monitoring unoccupied interiors for motions, sound, vibration, or other disturbances.
  • Alerting devices: These indicate an alarm condition. Most commonly, these are bells, sirens, and/or flashing lights. Alerting devices serve the dual purposes of warning occupants of intrusion, and potentially scaring off burglars. These devices may also be used to warn occupants of a fire or smoke condition.
  • Keypads: Small devices, typically wall-mounted, which function as the human-machine interface to the system. In addition to buttons, keypads typically feature indicator lights, a small multi-character display, or both.

Keypad

Keypads are Small devices typically wall-mounted. Which function as the Human Interface Machine to the System. In addition to buttons and a speaker. Keypads typically feature indicator lights with a small multi-character display. Keypads interconnect into the Alarm Control Panel. This may consist of direct wireing to the control unit, or wireless links with local power supplies.

Door and Window Contacts

The hermetically sealed reed switch is a two piece sensor that operates with an electrically conductive reed switch that is either normally open or normally closed when under the influence of a magnetic field as in the case of proximity to the second piece which contains a magnet. When the magnet is moved away from the reed switch, the reed switch either closes or opens, again based on whether or not the design is normally open or normally closed. This action coupled with an electric current allows an alarm control panel to detect a fault on that zone or circuit. These type of sensors are very common and are found either wired directly to an alarm control panel, or they can typically be found in wireless door/window contacts as sub-components.

Passive Inferred Detector

The passive infrared (PIR) motion detector is one of the most common sensors found in household and small business environments. It offers affordable and reliable functionality. The term passive refers to the fact that the detector does not generate or radiate its own energy; it works entirely by detecting the heat energy given off by other objects.
Strictly speaking, PIR sensors do not detect motion; rather, they detect abrupt changes in temperature at a given point. As an intruder walks in front of the sensor, the temperature at that point will rise from room temperature to body temperature, and then back again. This quick change triggers the detection.

PIR sensors may be designed to be wall- or ceiling-mounted, and come in various fields of view, from narrow "point" detectors to 360 degree fields. PIRs require a power supply in addition to the detection alarm control panel.

Glass Break Detector

The glass break detector may be used for internal perimeter building protection. Glass break acoustic detectors are mounted in close proximity to the glass panes and listen for sound frequencies associated with glass breaking.

Shock Sensor

These devices are physically mounted to detect tampering to the Item itself. The technology relies on an unstable mechanical configuration that forms part of the electrical circuit. When movement or vibration occurs, the unstable portion of the circuit moves and breaks the current flow, which produces an alarm. The technology of the devices varies and can be sensitive to different levels of vibration. The medium transmitting the vibration must be correctly selected for the specific sensor as they are best suited to different types of structures and configurations.