It is well known that there are two subsystems in the temperature system of constant temperature and humidity machine, namely, humidification and dehumidification subsystems. Steam humidification is generally used for humidification. Simply speaking, low pressure steam is injected directly into the box for humidification. With this method, the humidification speed is faster and the humidification control is more sensitive. Especially when the temperature is lowered, the forced humidification can be well realized.
There are two kinds of dehumidification of constant temperature and humidity machine, mechanical refrigeration dehumidification and drying dehumidification. The so-called dehumidification principle of mechanical refrigeration is to cool air below dew point temperature, so that water vapor with more than saturated moisture content condenses out, thus reducing humidity. The dryer uses an air pump to extract the air from the test box and inject the dry air into it. At the same time, the wet air is sent to the recyclable drying for drying. After drying, it is sent to the test box again and again for dehumidification.
The humidifying system of constant temperature and humidity machine is similar to that of heating system. It is the process of heating water to steam in heater and completes the purpose of humidifying. The dehumidification system is also completed by the refrigeration system, the evaporator is placed in the equipment; the high humidity gas inside meets the cold object to condense into liquid; so the high humidity gas in the repeated box body will be very few, so as to achieve the purpose of dehumidification.