The majority of alarm systems consist of an external siren/strobe light, an internal siren, keypad(s), a control panel and of course, sensors. There are also many other elements that can be added to a system, for example, wire free motion detectors, panic buttons, additional keypads and smoke detectors.
These are usually placed on the front of a premises, where they are plainly visible by both would-be attackers and passing traffic. They consist of a brightly flashing strobe light and a loud siren.
Usually just a bell, but can sometimes also contain a flashing strobe. These are used to attract the attention of the occupiers of the premises. They are usually located in a central location which can be heard from throughout the premises. Numerous sirens may be installed as required.Keypads
Keypads allow a user to arm and disarm the alarm system. They also display information valid to the user such as which zone was activated, when it was activated and currently activated zones. Numerous keypads may be installed as required.
This is the main processing unit of any alarm centre. All the other elements communicate with it either wirelessly or through cables.
There are numerous types of sensors. Some detect motion in a room, others detect the opening of a door or window and others detect the breaking of glass. A sensor can be classed as anything, which when activated, sends a signal to the control panel. Depending on the state of system, this may or may not result in an activation of the alarm system.
Wireless systems remove the need to physically connect each sensor in an alarm system to the control panel. They can be incorporated into an existing system, mixed with a wired system or used totally on their own.