What should do before using the high and low temperature rapid temperature change test chamber ?

 The overall temperature tolerance of the high and low temperature rapid temperature change test chamber is 2 ℃ or 3 ℃, considering measurement errors. The slow change in temperature and the temperature change in the workspace are determined, but in order to maintain relative humidity within the specified tolerance range, the temperature difference between any two points in the workspace must be kept within a small range.

 

If the temperature difference exceeds 1 K, the humidity standard does not comply with regulations. To maintain the required humidity, the temperature fluctuation should be maintained at 0.5 ℃ in the short term, and the temperature of the experimental sample should be stable between 3 ℃.

 

In high and low temperature tests, sometimes the product frosts, and the root cause is the increase in ambient temperature in the test chamber. Due to the thermal inertia, the surface temperature of the product is lower than the test ambient temperature, resulting in a cold and humid environment where air contact with the product surface is less than the leakage point, causing water vapor on the product surface to solidify into droplets.

 

In addition, if the product is in a sealed state, when the high and low temperature rapid temperature change test chamber cools down, the temperature on the inner wall of the product shell cools down faster than the gas inside the chamber, which causes the humid and hot gas inside the chamber to solidify into dew droplets on the inner wall of the product shell. Moreover, due to the fact that most products are not completely sealed, condensation usually occurs during the heating stage.

 

Condensing effect and commonly used materials for products. Inner cavity size. The speed of temperature regulation is related to its relative humidity. The worse the heat absorption of the material, the larger the inner cavity, the faster the temperature adjustment, and the higher the relative humidity, the stronger the condensation effect. As long as any situation disrupts the frost, it can be avoided.

 

Preparation work before testing the high and low temperature rapid temperature change test chamber:

 

1. If there are no specifications for the test standards used for determining high and low temperature tests, they can be based on the requirements of relevant product specifications.

 

2. Determine the high and low temperature test procedure, test standards, temperature points, test time, etc.

 

3. Determine the compliance requirements for high and low temperature testing, that is, describe the operating status of the test samples and inform in advance how the product malfunctions.

 

4. High and low temperature tests must be carried out, such as a spectrum analyzer and power cord. Laptops. DC electronic loads and related auxiliary equipment.

 

5. Determine whether the testing requirements can meet the requirements of the same laboratory, and whether the capacity of the temperature chamber can be placed according to the specific sample specifications.