Temperature and humidity test chamber temperature indicators include temperature range, temperature uniformity, and temperature fluctuation. When the temperature is adjusted in the test, many factors often affect the steady state of temperature uniformity. In order to get the small error of the data, the small In this article, some common influencing factors are summarized for users:
1) Heat load factor → If enough test samples are placed in the working chamber of the test chamber to affect the overall internal heat convection, it will inevitably To some extent, it affects the internal temperature uniformity. For example, when placing LED lighting products, the products themselves emit light and generate heat, which becomes a thermal load, which has a great impact on the uniformity of the temperature;
2) Heat transfer → due to the different heat transfer coefficients of the front, rear, left, right, upper, lower and upper sides of the working room box wall, some small details such as thread holes, detection holes and test holes will cause local heat dissipation and heat transfer, so the equipment box temperature is uneven and heat transfer by convection of the box wall radiation will also be uneven, which will affect the temperature uniformity;
3) Heat radiation → design problems lead to the test box in It is difficult to achieve a uniform and symmetrical structure in the design of the internal structure and space. The asymmetrical structure of the temperature and humidity test chamber will inevitably lead to deviations in temperature uniformityinternal. This level is mainly reflected in the design of the sheet metal and its processing. , such as air duct design, heat pipe placement, fan power size, etc. ;
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