The SecurityLine motion sensors are the recommended triggers for most secure zones because, when properly placed, they allow for the cameras to trigger and record any time that there is motion in the camera's same field of view. For a stand-alone SecurityLine System, a motion sensor is required. The motion sensor may also be located at a distance apart from the camera(s).
The Infra-red sensor will detect and trigger any time that there is motion in the sensor's range. It has a 110 degree range at max 10.6m distance and can be mounted for full coverage of an area or with dedicated out-of-range zone (ex. for a "pet alley").