The OSI-RE-SS is actually a reflector- kind linear optical beam smoke detector made to work for a element of fire alarm devices. The beam operates totally on the principle of sunshine obscuration utilising an Infra-Crimson beam. OSI-R-SS is actually a four-wire conventional reflector-kind linear optical beam smoke detector to be https://www.firesense.co.uk/type/conventional-fire-system/conventional-beam-detectors/