A range of applications are mainly used in measuring nitrogen content in nature, such as: field soil, beverage, food, chemical, agriculture. Second, characteristics: a new long-life design, advanced microcomputer intelligent control, LCD color screen operation, Chinese menu-driven man-machine dialogue interface. High degree of automation (good digestion samples directly autosampler complete the whole process of analysis and calculation), reliable, low running costs. From the sample, automatic analysis unattended operation of the process. Automatic cleaning system to prevent cross-contamination of samples, to a greater extent to ensure the accuracy and precision of operator safety and results. Selection of international quality standard components to ensure system reliability. Autosampler system, even if the sample size is not also realize fully automated operation. Third, the technical indicators 1, measuring range: 0 ~ 250mgN 2, the measurement accuracy: ± 0.5% (RSO) 3, measurement accuracy: ≤ ± 0.5% (RE) 4, detection time: ≤10min / sample 5, the data storage capacity : Not less than 6000 times 6, Display: LCD, Chinese menu 7, ambient temperature: 10 ~ 40 ℃ 8, Humidity: maximum 80% (relative) 9, the power supply voltage: AC200 ~ 240V / 50 / 60HZ automatic feed Sample unit: Injector capacity: 12