本文介绍一种符合内燃机台架试验标准要求的新型大气状况实时测量仪。该仪器在发动机试验过程中，可同时检测试验现场的温度、湿度和大气压力。它使用方便，准确度高，并有ＴＴＬ电平的ＢＣＤ码输出，能与计算机方便地连接，可实现微机数据采集系统的自动修正。文中着重介绍了温度、湿度的检测系统，阐述了运用干湿球原理，在温度测量基础上，经逻辑运算处理得到相对湿度，把湿度测量转化为测量方法比较成熟的温度测量的原理和方法。 This article presents a new atmospheric conditions real-time measuring instrument that conforms to the test standard of internal combustion engine bench. The instrument in the engine test process, the test site can simultaneously detect the temperature, humidity and atmospheric pressure. It is easy to use, high accuracy, and TTL level BCD code output, can be easily connected with the computer, enabling computer data acquisition system automatically correct. In this paper, the temperature and humidity detection system is introduced emphatically. The principle and method of temperature measurement based on the wet and dry bulb principle, the relative humidity obtained through logic operation and the humidity measurement are transformed into the more mature temperature measurement methods.