The standard sensor used in home alarm systems is the hermetically sealed reed switch. The hermetically sealed reed switch is a two piece sensor that operates with an electrically conductive reed switch that is opened or closed if an intrusion occurs. These sensors are often used on doors and windows because of their low cost and reliability. They are the most basic of all sensors.
Install Infrared Detectors to Save Energy
It is now common practice to install Passive Infrared (PIR) motion detectors in households and small business environments. These sensors do not require any power from standard electrical outlets, they actually generate its own energy entirely from the heat of its surroundings. These innovative detectors do not actually detect motion, but instead abrupt changes in temperature. Infrared detectors are industry standard and come highly recommended by Central Alarm.
Echolocation Employed in Alarms
Ultrasonic detectors tend to be the most scientifically complex detectors available to date, and also the most interesting. These sensors function similarly to dolphin sonar. The sensors emit a sound frequency of 15kHz and 75kHz which is undetectable by the human ear. This frequency is aimed at a solid surface that reflects the sound back to the receiving sensor. When the surfaces are static, the waves remain at a constant frequency. However, when an intruder walks in front of a sensor the wave frequency will be disrupted and the alarm will be triggered!
Glass Break Detection
There was once a criminal in the Phoenix, metropolitan area known as the rock burglar. This outlaw made his bones by stalking homeowners, discovering when they left on vacation, and then tossing a rock through their back window and ravaging the house unchallenged and undetected. However, houses with glass break detection sensors were impregnable by the rock burglar. These sensors function similar to ultrasonic detectors, except they are specifically engineered to protect any crack or fragment in a houses windows.