Instrument body analyzer uses a modular design approach, conducive to integration. The main instrument body by meter box unit, the high temperature gas chamber means, the temperature control module, wherein the meter box unit by the circuit board, a laser, a signal processing unit. High temperature gas chamber from the laser emitting unit, laser receiving unit, a high temperature heating chamber, the gas composition. Temperature control module consists of a solid-state relays, intelligent temperature controller, temperature sensor. Lasers using butterfly packaged semiconductor laser, laser light emitted from the light transmitted through the fiber to a high temperature gas chamber laser emitting unit, laser light passes through the measured gas flows through the gas chamber, the high temperature gas chamber receiving sensor circuit detects been measuring gas absorption with the laser beam, converts the optical signal into an electrical signal transmitted to the electrical control unit in a signal processing unit, signal processing unit via the signal processing after the calculated spectra measured gas concentration. Specifications Measurement method: laser absorption spectroscopy (TDLAS) components and measuring range: NH3: 0-10ppm (MIN) 0-100% (MAX) Indication error: ± 2% FS Repeatability: ± 2% FS Response time: ≤90S zero drift: 2% FS / 7d span drift: 2% FS / 7d Protection: IP65 analog interface: 4 4-20mA output (can be configured with a maximum load capacity of <800 Euro) 2-way 4-20mA inputs ( flexible configuration, 100 ohm load) Relay output: 14 channels can be configured, DC30V2A switch inputs: 6-way, can be flexibly configured communication interfaces: l Road RS232, l Road RS485, support Moddbus protocol Power: 220 ± l5% VAC / 2KW sample flow rate: 1.5 ± 0.1 L / min Ambient temperature: -20 ℃ -50 ℃ Humidity: 0% -95% RH