Intelligent Photoelectric Smoke Detector is an addressable fire alarm device cooperating with GST intelligent fire alarm control panels to build a fire detection system. It shows fire alarm by LED indicators and transmits the fire signal to the control panel. Using infrared scattering technology, the smoke density can be detected. The detector receives very weak infrared light under normal smokeless condition. If smoke particles enter the chamber, the received light signal will increase by scattering. When smoke density reaches a pre-set level, the detector will alarm out. In order to reduce interference and power consumption, the emitting circuit works in pulse mode to prolong the life of IR LED.