So2 analyzer adopts ultraviolet fluorescence method and combines with advanced microprocessor technology. It provides accurate and reliable detection of S02 at ppb ppm level which meets the requirements of ambient gas monitoring and online monitoring of pollution source with dilution method. The operation principle is based on ultraviolet fluorescence method. After absorbing the ultraviolet energy g, 502 molecule is inspired to excited state and once it returns to ground state , it will release specific fluorescence. The intensity of fluorescence could realize quantitative measurement. Measurement stability is greatly improved by using timed dark current measurement to compensate photomultiplier drift and reference detector to calibrate the change of UV light intensity. With high-efficiency hydrocarbon remover and unique optical design the analyzer can effectively clear up inexactitude caused by interference. This analyzer can completely control all functions and also provides online instruction for important work parameters. Real time auto compensation for temperature and pressure will be made during measurement. 0 Measuring range: 0-500ppb (other rangers are customazible) 0 Dual measurement range and auto set range 0 Multiple functional operations by microprocessor 0 Task software isallowed to monitortest data during operation 0 Continuous self-checking with alarm function 0 Self-check of light intensity attenuation 0 Bidrection RS-232 port for remote control 0 Digital output working parameter 0 Response time optimized by signal filter technology of self-adaptation 0 Compensation function for temperature and pressure 0 USB and Ethernet interface 0 Colorful display and screen touch operation 0 Large memory and history data saved automatically Address:No. 8, Haitai Development 5th Road, Huayuan Industrial Park, Binhai High-Tech Zone, Tianjin