The test methods of the high and low temperature test chamber are divided into non-heat dissipation test samples and heat dissipation test samples (that is, whether the tested sample has heat in the industry). The following is a comparison of the application of various test methods: 1. Non-heat dissipation test sample and heat dissipation test sample: After the temperature of the test sample has stabilized during the condition test, the temperature of the hottest spot on the surface of the test sample is 5 degrees higher than the surrounding atmospheric temperature when measured under free air conditions (ie without forced air circulation) Above, it is considered to be heat dissipation, otherwise it is a non-heat dissipation test sample. All storage samples and no electricity or load during the test, the test samples are non-heat dissipation test samples, and the test adopts the low temperature test method. 2. Non-heat dissipation test sample: temperature gradual change test of temperature mutation test box (the former is a rapid temperature change test box and the latter is a high and low temperature test box) Temperature mutation test Aa: first adjust the temperature of the test box to the specified test temperature, and then put the test sample with room temperature. This test method is suitable for the case where the temperature mutation does not cause operation on the test sample. Temperature gradual change test Ab: first put the test sample with room temperature into the test box with the same room temperature, and then start the cold source to gradually cool the temperature in the box to the specified test temperature. If the test sample is too large or too heavy, or because of For complex function test wiring, when the mutation test cannot be placed in the low temperature box without frosting, the test Ab should also be used. 3. With and without forced air test of the heat dissipation test sample: the method of ensuring uniformity fluctuation in the industry is to use the wind circulation mode, the fan is driven by the motor to generate the wind circulation to form the wind speed direction, and the test without forced air circulation is to simulate free air A test affected by conditions is more suitable for the test of heat dissipation test samples. The test with forced air circulation is that when forced air circulation is not used or it is difficult or impossible to guarantee the specified test conditions, there are two forced air in the test method Ad Method: A and B. Method A is used when the test chamber is so large that it can meet the test requirements without forced air circulation, but it can not maintain the specified low temperature without forced air circulation in the box, that is, the cooling or heating of the high and low temperature test chamber When forced air circulation is required. Application comparison of various test methods in high and low temperature test chamber Pneumonia Mask,Corona Virus Mask,Protective Masks For Virus,Coronavirus Pneumonia Face Mask ShanDong YongFang Sanitary Products Co.,Ltd , https://www.sdyongfang.com