The test sample of the high and low temperature test box is considered to be heat-dissipating only when the temperature reaches a stable temperature (see the corresponding content in GB / T2421), measured under free air conditions (for example, low gas flow rate circulation) The temperature of the hottest spot on the surface of the test sample exceeds the temperature of the air around the test sample by more than 5K. When the relevant specifications require storage or transportation tests, or no load is specified during the test, the low temperature test Ab is applicable.
Non-heat dissipation test sample: application comparison of temperature mutation test and temperature gradient test
Temperature mutation test Aa: first adjust the temperature of the high and low temperature test chamber to the specified test temperature, and then put the test sample with room temperature. This is a simple and time-saving method. This test method is suitable for known temperature mutations on the test sample The situation when there is no damage.
Temperature gradual change test Ab: first put the test sample with room temperature into the test box which is also room temperature, and then gradually cool the temperature of the test box to the specified test temperature. This test method will not damage the test sample due to temperature changes.
Note: If the size of the test sample is too large, or due to the complicated function test wiring, it can not be placed in the low temperature test box without frosting during the mutation test, the test Ab should also be used.
The test of whether the heat dissipation test sample has forced air circulation
The better test method of the heat dissipation test sample of the high and low temperature test box is carried out without forced air circulation. If it is difficult to meet this requirement, the test Ad method can be used when the heat dissipation test sample has forced air circulation.
There are two methods of forced air circulation test: Method A and Method B. Method A is used when the test chamber is large enough without forced air circulation to meet the test requirements, but the forced low temperature environment cannot be maintained without forced air circulation in the test chamber. Method B is used when the high and low temperature test chamber is too small to meet the test requirements without forced air circulation.
If you want to know more similar products of the test box, please call our company! 010-68176855 (switchboard) or log on the company website:
small pet cage,large pet cage,homey pet cage,pet hammock for cage
Ningbo XISXI E-commerce Co., Ltd , https://www.petspetsaccessories.com