1. refrigeration system: the refrigeration system of the constant temperature and humidity test box is one of the important components of the constant temperature and humidity test box.
2. Heating system: Compared with refrigeration system, the heating system of constant temperature and humidity test box is relatively simple. It is mainly composed of high-power resistance wires. Because the heating rate required by the constant temperature and humidity test chamber is relatively high, the heating system power of the test chamber is relatively high, and the bottom plate of the test chamber is also equipped with a heater.
3. Control system: The control system is the core control part of the constant temperature and humidity test chamber, which determines the important indexes such as the heating rate and accuracy of the constant temperature and humidity test chamber. At present, most of the controllers of the test chamber adopt PID control, and a few adopt the control mode of combining PID and fuzzy control. Because the control system basically belongs to the category of software, and there will be no problems in the use of this part.
4. Humidity system: The humidity system of the constant temperature and humidity box is divided into two subsystems: humidification and dehumidification. The humidification method of constant temperature and humidity test box generally adopts steam plus wet method, that is, low pressure steam is directly injected into the test space for humidification. This humidification method has the advantages of strong humidification ability, high speed and sensitive humidification control, and can easily realize forced humidification, especially when cooling down. There are two dehumidification methods in the constant temperature and humidity test chamber: mechanical refrigeration dehumidification and dry dehumidification. The dehumidification principle of mechanical refrigeration dehumidification is to cool the air below the dew point temperature, so that the water vapor greater than the saturated water content condenses and precipitates, thus reducing the humidity. Dehumidification of the dryer is to use the air pump to pump out the air in the constant temperature and humidity test box and inject dry air, at the same time, send the wet air into the recyclable drying room for drying, and then send it into the test box after drying, and so on. At present, most constant temperature and humidity test chambers adopt mechanical refrigeration and dehumidification, while dry dehumidification can make the dew point temperature lower than 0℃. Suitable for occasions with special requirements, but the price is more expensive.
5. Sensor system: The sensors in the constant temperature and humidity test chamber are mainly temperature and humidity sensors. Platinum batteries and thermocouples are widely used as temperature sensors. There are two methods to measure humidity: dry-wet bulb thermometer and solid-state electronic sensor.
6. Air circulation system: The air circulation system of the constant temperature and humidity test chamber is generally composed of a centrifugal fan and a motor driving it. It provides air circulation in the constant temperature and humidity test box.
Provided by Guangdong Sanmu Technology Co., Ltd.