Reference Book: Star Wars Saga Edition Galaxy at War
Motion Detectors are among the most widely used Sensors in the galaxy. Not every Battlestation employs them, but they are often tied to Security Cameras so that the cameras can conserve energy and remain dormant when not in use. Unlike normal Sensors, Motion Detectors are simple devices that have two modes: active and inactive. They do not register the number of beings or objects moving through an area, only that something is moving. A Motion Detector is triggered if any creature moves 1 square or more within the detector's area. When triggered, the detector immediately performs a simple, predetermined action, such as activating a Security Camera, powering the lights, signaling the nearest Security Control Room, opening a door, and so on.
Due to the simplicity of Motion Detectors, they are almost impossible to avoid. The best approach is to deactivate them in a nearby Security Control Room. Trespassers can also shut down a Motion Detector by making a Moderate Perception check to locate the correct conduit and an Easy Mechanics check to cut the power. Usually, a detector's conduit is found in a service and maintenance access tunnel.