Thermal shock test equipment-----About defrosting

Why should the cold and heat shock equipment be defrosted?

       The frost in the thermal shock box grows on the energy storage components in the pre-cooling zone.

       Why is it always necessary to defrost the hot and cold shock? We know that the thermal shock is to exchange heat through the airflow conversion between the three boxes to achieve the shock effect. These three boxes are isolated from the air outside the box. That is to say, the three boxes are airtight relative to the outside world. Since it is a confined space, their moisture content is quantitative, and it is impossible to produce extra moisture out of thin air. In other words, theoretically speaking, there should be no frost in the pre-cooling zone. But going back to the source, where does the moisture come from?

       Only the test area of these three cabinets can be opened by the customer to place the product. It is possible to introduce moisture only after the test area is opened. Therefore, one of the sources of moisture is the customer's door opening operation. We do a complete set of impact tests, and the door is not allowed to be opened in the middle, otherwise the test will fail.