Description: Video Motion Detection (VMD) sensors operate through almost any good quality CCTV camera providing both a detection of activity & observation of the events progress.
The VMD sensor system monitors changes in the camera's field of view and if a change occurs through an intruder entering the scene an alarm condition is generated.
Better systems also include an image tracking feature which can monitor a number of separate intruders simultaneously by drawing a different coloured line around each of them and leaving a trail line of where they have been.
Classification: Passive - Overt or Covert - Line of Sight
Application: Excellent addition to other detection systems and for covering large or difficult areas. Ideally used with both overt & covert cameras
Advantages: Can be used with existing cameras without additional field wiring, can cover a wide field of view, helps guards track an intruder even in low light conditions and removes the intruder's ability to hide, relatively low cost, easy to maintain
Possible Causes of Nuisance Alarms: Severe adverse weather, large animals, flocks of birds, blown debris, movement of camera
Methods of Defeat: Tunnelling, blind spots, very slow movement, attack on or the blinding of camera.