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Tell me about the maintenance method of compressor for constant temperature and humidity equipment test box

Tell me aboutConstant temperature and humidity equipmentMaintenance method of Test box compressor



Compressor is the core component of constant temperature and humidity test box, which plays a direct role in low temperature test. Therefore, usually for the maintenance of the compressor is very important. According to the experience of Yasumoto electronics in the ring test industry for many years, the following maintenance suggestions are summarized:
  
1, in the test process do not start the compressor frequently, and the compressor start time interval of more than 15 minutes;
  
2, the workplace voltage must be stable, if the voltage instability, will lead to too large or too small current, long time in this environment operation will cause great damage to the compressor, it is recommended to use voltage regulator to connect the constant temperature and humidity test box;
  
3, to ensure that the working environment well ventilated and no dust, to maintain the compressor surface clean, if the long-term do not use constant temperature and humidity test box, the equipment should be placed in the space as dust-free;
  
4, constant temperature and humidity test box should be placed in accordance with the specified environment: temperature: 5℃~30℃, Humidity: ≤85%RH, air pressure: 86~106kpa
  
5, the equipment around the appropriate maintenance space, nearby no strong electromagnetic radiation source, ground leveling, well-ventilated, does not contain flammable, explosive and corrosive gases.
  
If you do the above points, basically master the maintenance of the compressor. Can ensure the operation of your normal equipment, effectively extend the service life of the equipment.

 

There are many ways to represent humidity, and in the case of test equipment, humidity is usually described with the concept of relative humidity. Relative humidity is defined as the ratio of water vapor pressure in air to the saturated vapor pressure of the water at that temperature and expressed as a percentage. According to the nature of water vapor saturation pressure, the saturation pressure of water vapor is only a function of temperature, which is independent of the air pressure at which water vapor can be located, and people have sought to express the relationship between water vapor saturation pressure and temperature through a large number of experiments and finishing, which has been widely used in engineering and metrology should be the Govgrach formula. It is used by the meteorological Department to compile a humidity check sheet.


The process of humidification is actually to increase the pressure of water vapor, the initial humidification method is to spray water to the wall of the test box, by controlling the water temperature so that the surface saturation pressure is controlled. The water on the surface of the box wall forms a larger surface, and the addition of water vapor pressure to the box through diffusion in the box on this surface increases the relative humidity in the test chamber, a method that appeared in the 50 's. Because the humidity control at that time is mainly with the mercury electric contact type conductive meter to carry on the simple switching quantity adjustment, for the large lag hot water box water temperature control adaptability is poor, therefore the control transition process is longer, can not meet the alternating heat and humidity to the humidification quantity demand more, more importantly in the box wall spray, Inevitably, there are water droplets on the test products to form different degrees of pollution to the test. At the same time, there are certain requirements for in-box drainage. This method was quickly replaced by steam humidification and shallow water plate humidification. But there are some advantages to this approach. Although its control transition process is long, but the system stability after the humidity fluctuation is small, more suitable for constant wet and hot test. In addition, the water vapor does not overheat during humidification and does not increase the extra heat in the system. Also, when controlling the spray water temperature so that it is lower than the test requirements of the main point of temperature, the sprinkler has a dehumidification effect.


With the development of hot and humid test from constant hot and humid to alternating heat and humidity, it is required to have a fast humidification reaction ability, spray humidification can not meet the requirements, steam humidification and shallow water plate humidification methods began to be widely used and developed.