The beam operates primarily on the principle of sunshine obscuration employing infrared. The OSI-RI detector is actually a mixed transmitter/receiver which can be right connected to an intelligent detector circuit in LiteSpeed® or CLIP manner. Power and connectivity manifest from the imager only plus the OSID-R only needs a single https://www.firesense.co.uk/type/addressable-fire-system/addressable-beam-detectors/