Motion alarm used in security systems, has ECU that activates second sensor system only if movement is detected by first sensor system in coverage area

摘要

The motion alarm (3) has a first sensor system with an infrared sensor stretched in a large coverage area to detect movement. A second sensor system is laid in a smaller area within the coverage area to detect movement. An electronic control unit (ECU) activates the second sensor system for a preset duration or certain action only if movement is detected by first sensor system.