Security Sensors and Motion Detector Systems

Motion detection systems detect movement in areas covered by the security sensors. Some motion detection systems transmit high frequency radio wave signals into the secure area of a room or hallway. Other systems may use infrared light to detect heat changes, such as when a person (body heat) walks by the infrared sensors. If a person moves in the range of the motion sensors, the alarm (audible, visual, or silent) is activated.

Some motion detection systems use lasers and photoelectric beams. The laser is a light beam shot across to the other side of the room, doorway or passageway. If this light beam is interrupted the unit's alarm signal is activated. Other motion detecting systems detect vibration. Many car alarms have this feature to alert the owner that something has bumped into his automobile or somone has broken into it.

Outdoor motion detecting systems are often used to monitor driveways and work when movement causes floodlights to illuminate an area of the driveway. They usually use an infrared detection sensor which senses temperature changes. Unfortunately, squirrels, cats and sudden wind gusts can turn the lights on and off repeatedly, which makes them annoying to many homeowners.

Learn more about home security systems.