Sensors are able to detect rapid changes in the environment, such as a window opening or glass breaking which may indicate an intrusion or breach of security. The information is then sent to an alarm system’s controller which notifies the central monitoring station (if the client uses a monitoring service).
Alarm sensors are available in a variety of types and price ranges. Some detect motion, others sense door and window openings, and some are able to detect glass breaking or the pressure of a footstep on carpeting. Here is information on some of the most commonly used types of sensors.