This guide details the switches, sensors and other devices that commonly guard a building’s perimeter when an alarm system is installed. These sensors are used primarily on doors and windows.

The most common member of this family is the magnetic switch, the little pair of white rectangular boxes seen above doors of most businesses

The second line defense is the area sensor. Area sensors monitor a specific area rather than a specific point of entry. These are often called motion detectors, since anyone moving about a guarded room will be detected. The way in which these sensors achieve this goal varies between components.

Window foiling is another sensor which many are familiar with. It graces the windows of nearly every store in America, and rightfully so, it is very difficuly to bypass successfully BUT NOT IMPOSSIBLE!

The ultrasonic system consists of a transmitter, which emits a frequency that lies above the human threshold of hearing, and a receiver, that monitors the incomming frequency. The entire system is generally self- contained in one unit, although occasionally on transmitter is used with several receivers.

The photoelectric alarm, or “electric eye” is a fairly common alarm today - it lets off a buzz when you walk into a store.

Passive Infra-Red alarms, or PIRs are so called because they do not emit Infra-Red energy, but merely detect a change in it. A PIR probes its monitoring area, and if any changes are detected in Infra-Red (heat), it activates the alarm.

The microwave alarm system is another transmitter/reciever motion detector, and is unquestionably the most difficult to successfully bypass.

Learn all that there is to know about various types of burglar alarms and their various elements and sensors. This shocking guide reveals what the are, how they work and how they are beaten!

Followings systems of alarms are described in this guide:

  • Magnetic Contact Switches
  • Window Foiling
  • Ultrasonic Alarm System
  • Photoelectric Alarms
  • Passive Infra-Red Alarms
  • Microwave Systems