Exploring the Method and Protectation of High and Low Temperature Humidity Chambers and Humidity Temperature Chambers

I. Overview of Temperature and Humidity Measurement Method of High and Low Temperature Humidity Chamber：
Electric and electronic products are almost used in various climatic conditions in China. Products should be able to withstand the influence of severe climatic environment, which requires pre-knowledge of detailed climatic information encountered by products in design stage. The data of outdoor temperature and humidity of the world in many years have been collected and summarized, which can be conveniently expressed through climate maps. Related data in China is based on outdoor temperature and depth from 1961 to 1980. However, to collect these data, we need to use environmental testing equipment such as High and Low Temperature Humidity Chamber, which belong to Humidity Temperature Chamber.

Temperature Humidity Chamber | Thermal Chamber

In addition to outdoor temperature, the temperature influence on certain products is also related to many other environmental parameters, such as solar radiation, wind speed, heating of adjacent equipment, etc. The influence of temperature depends on temperature, humidity changes and impurities in moist air. Although the time when temperature and humidity extremes appear in one day is short, the influence is still great. In some occasions, such as when the product’s thermal time constant is large, or other occasions with water vapor permeation, the average value of temperature and humidity of a certain may be more important. Therefore, the following two average value indicators are adopted in this section: one is the average value of annual extremes appearing only in a short time; the second is the average value of the annual extreme value appearing in a longer time. Temperature influence is also related to solar radiation, wind speed, heating of adjacent equipment, etc.; humidity influence is also related to temperature, thermal decomposition and impurities in the air. This section does not consider the reliability issue, but only gives the extremes and combination values of temperature and humidity. If we want to study reliability problems, we should also master the statistical distribution data of temperature and humidity. When considering water vapor diffusion through materials, we also need this kind of data. Above is the temperature and humidity testing method of High and Low Temperature Humidity Chamber, hoping to be helpful for our customers.

II.Proper Maintenance of High and Low Temperature Humidity Humidity Chamber Methods:
Environmental test equipment is varied, but the most widely used environmental test equipment is high and low temperature, humidity and hot test box, and now the most popular is combined with high and low temperature, humidity and hot as a test box. High and low temperature humidity and hot test box, its repair difficulty is larger than other environmental test equipment, and has representative characteristics. Next, take the high and low temperature humidity and hot test box as an example to talk about the structure and some common faults and troubleshooting methods of high and low temperature humidity and hot test box.

(1) Common Structures of High and Low Temperature Humidity and Hot Test Box
In addition to the correct operation according to the operation regulations, the test personnel should also have a certain understanding of its structure. The high and low temperature humidity and hot test box is composed of box body, air circulation system, refrigeration system, heating system and humidity control system. The air circulation system usually adopts an adjustable air supply direction structure: the humidification system adopts either the boiler humidification or the surface concealment: the cooling and dehumidification system adopts the air conditioning working conditions refrigeration structure: the heating system adopts the electric fin heating and the electric stove to heat directly: the temperature and humidity test method adopts the wet and dry ball test method, and also uses the direct measurement method of the humidity sensor: the control and display operation interface adopts the independent temperature and humidity control and the temperature and humidity combined controller.

(2) Some Common Faults and Troubleshooting Methods of High and Low Temperature Humidity and Hot Test Box:
1.When the temperature change does not reach the test temperature in high temperature test, the electrical system can be checked and the fault can be eliminated one by one. If the temperature rises very slowly, it is necessary to check the air circulation system, to see if the adjustment baffle of the air circulation system is opened normally, otherwise, to check whether the motor of the air circulation system runs normally. If the temperature is too high, it is necessary to adjust the PID setting parameters. If the temperature rises directly and the over temperature protection, the controller fails and the control instrument must be replaced.

2.When the test index is not reached in the low temperature test, it should be observed whether the temperature drops very slowly or the temperature rises after a certain value. For the former, it is necessary to check whether the laboratory is dried before the low temperature test, whether the test samples are placed in the laboratory after the laboratory is kept dry, whether there are too many test samples in the laboratory of high and low temperature humidity and hot test box, so that the air in the laboratory cannot be fully circulated, and after excluding the above reasons, it is necessary to consider whether there is a fault in the refrigeration system. It is necessary to ask the professional personnel of the manufacturer for maintenance. The latter phenomenon is that the environment of the equipment is not good, the environment temperature of the equipment placement, the position of the placement (the distance between the back of the box and the wall) must meet the requirements (it is specified in the operation and use instruction of the equipment).

3.When the high and low temperature humidity and hot test box is used in the humidity and hot test, the actual humidity will reach 100% or the actual humidity is greatly different from the target humidity, and the value is much lower. The phenomenon of the former may be caused by the dryness of the fabric on the wet ball sensor, so it is necessary to check whether there is water in the water tank of the wet ball sensor. The water level is automatically controlled by a water level controller. Check whether the water supply system of the water level controller is supplied normally, whether the water level controller is working normally. Another possibility is that the wet ball fabric will become hard due to long use time or purity of water supply, which can not absorb moisture and face dryness. Just replace or clean the fabric can eliminate the above phenomenon. The phenomenon of the latter is mainly that the humidification system does not work. Check the water supply system of the humidification system, whether there is a certain amount of water in the water supply system, whether the water level controller controlling the water level of the humidification boiler is normal, and whether the water level in the humidification boiler is normal. If all the above are normal, it is necessary to check the electrical control system, which requires professional maintenance personnel to inspect and repair.