Ethiopian base station archive room dehumidifier base station air conditioner base station constant temperature and humidity unit
HEAD-POWER AIR CONDITIONING manufacturer Ethiopian base station archive room dehumidifier base station air conditioner base station constant temperature and humidity unit.
Base station archive room dehumidifier base station air conditioning base station constant temperature and humidity unit working principle:
The constant temperature and humidity machine is composed of a refrigeration system, a heating system, a control system, a humidity system, an air circulation system, and a sensor system. The above systems are divided into two major aspects of electrical and mechanical refrigeration. The working principle and working process of several main systems are described below.
1. Refrigeration system: The refrigeration system is one of the key parts of the constant temperature and humidity machine. In general, the refrigeration methods are mechanical refrigeration and auxiliary liquid nitrogen refrigeration. Mechanical refrigeration uses vapor compression refrigeration, which is mainly composed of compressor, condenser, throttle mechanism and evaporator. If the temperature of our test is to reach -55 ℃, single-stage refrigeration is difficult to meet the requirements, so the cooling method of the constant temperature and humidity machine generally uses cascade refrigeration. The refrigeration system of the constant temperature and humidity machine is composed of two parts, called high temperature part and low temperature part, each part is a relatively independent refrigeration system. The evaporation of the refrigerant in the high temperature part absorbs the heat from the refrigerant in the low temperature part and vaporizes; the evaporation of the refrigerant in the low temperature part absorbs heat from the object to be cooled (air in the test machine) to obtain the cooling capacity. The high temperature part and the low temperature part are connected by an evaporative condenser, which is both the condenser of the high temperature part and the condenser of the low temperature part.
2. Heating system: The heating system is relatively simple compared to the cooling system. It is mainly composed of high-power resistance wire. Due to the relatively large heating rate required by the test, the power of the heating system is relatively large, and a heater is also provided on the bottom plate of the testing machine.
3. Control system: The control system is the core of the integrated test chamber, which determines the important indicators such as the heating rate and accuracy of the test machine. At present, the controller of the testing machine mostly adopts PID control, and a small part adopts the control mode combining PID and fuzzy control. Since the control system basically belongs to the category of software, and this part is generally used, there will be no problems.
4. Humidity system: The temperature system is divided into two subsystems: humidification and dehumidification. The humidification method generally adopts the steam humidification method, that is, the low-pressure steam is directly injected into the test space for humidification. This humidification method has a high humidification capacity, fast speed, and sensitive humidification control, and it is easy to realize forced humidification especially when the temperature is lowered.
