Intrusion Detectors
Intrusion detectors are sensing devices that use a variety of technologies to detect intruders within a protected area. They are utilized in alarm systems inside of homes, businesses, schools, etc. and other places such as outside areas. Intrusion detectors utilize the following methods: sound, temperature variation, motion, vibration, blocking of a beam, pressure and the opening or closing of a circuit through switches.
The following devices represent the most common types of detectors utilized in alarm systems:
- Magnetic Switch – Detects the opening or closing of a door or window.
- Passive Infrared (PIR) – Detects changes in ambient temperature of a room or protected area, such as a warm body in a cool room.
- Combination PIR and Microwave – Two different sensing technologies are used in combination for false alarm reduction in areas where a PIR may not be suitable.
- Glass Break – Detects the frequency of breaking glass.
- Photoelectric – Detects blocking of an invisible light beam.
- Vibration – Detects vibrations as well as shock from hard impact on rigid surfaces.
- Pressure – Detects increased pressure (weight) on soft and hard surfaces.
- Tamper Switch – Detects removal of a cover on a PIR, opening of an alarm panel, a cabinet or safe, through the opening or closing of a circuit.
- Combination PIR and Camera – Detection combined with visual verification.
- Motion Sensing Cameras – Detect motion through software in the camera, or through a digital video recorder.
Depending on the application and degree of risk, multiple types of intrusion detectors can be utilized within an alarm system for maximum detection capability and protection.