The constant temperature and humidity chamber is a high-precision instrument, so be sure to pay attention to the points when purchasing. First, the size selection generally constant temperature and humidity size is determined according to the size of the test product Second, constant temperature and humidity box power supply selection Whether it is 220V or 380V are three-phase power interface, if the temperature is below -40 degrees, and the box is above 225L, it is recommended to choose 380V four-phase power interface, because this is the whole The power consumption of the laboratory is relatively stable, which is also good for the life of the equipment itself. Third, air cooling and water cooling options: constant temperature and humidity box is generally sufficient to use air cooling, water cooling is generally a large constant temperature and humidity chamber or large box of rapid temperature rise and fall test machine, the general thermal shock test box is water cooled More Fourth, the constant temperature and humidity chamber use environmental environment test, especially the reliability test, the test period is long, the test object is sometimes a high value military product, during the test, the test personnel often have to operate or test around the scene, Therefore, environmental test equipment is required to have the characteristics of safe operation, convenient operation, reliable use and long working life to ensure the normal operation of the test itself. Various protection, warning measures and safety joints of test equipment