In the previous section, we described the test summary of the sudden change of temperature in the high and low temperature test chamber. In this section, we describe the test procedures for the test. The test samples at room temperature are in the unpacked, unpowered, "ready to use" state, according to the normal position Or put it in the test box at other specified locations. At this time, the temperature in the test box is also called room temperature. When the test sample is actually used with a specific mounting frame, these devices should be used during the test. Carry out the test together. The temperature measurement of the test chamber is carried out in accordance with the requirements specified in the standard. The temperature in the high and low temperature test chamber is adjusted to a temperature value that meets the severity level, and there is sufficient time for the sample to reach temperature stability. For functional testing, it must be Give the test sample energized or electrical load according to the relevant specifications, and check to determine whether it can achieve the specified function (Note: At this time, the test sample is in operation or under load conditions, as long as the surface temperature does not exceed the surrounding atmospheric temperature 5K, all are considered Is non-radiating).

The continuous dark exposure of the test sample under low temperature conditions should be counted from the time when the temperature reaches stability (when the temperature of the test chamber reaches the set temperature, there will be a buffering process, and the temperature deviation and fluctuation in this process will be large. The phenomenon will continue for 10-30min, and the previous temperature point will reach a stable state). At the end of the condition test, the test sample should be restored to its original state. For the test sample that is energized or loaded with electricity, the power should be stopped or unloaded before the recovery procedure. Go to load.

Relevant specifications may specify loading or measurement during or at the end of the conditional test (the test sample is still in the high and low temperature test chamber). If necessary, the measurement items and time shall be specified. During the measurement, the test sample shall not be taken out of the test chamber. (Note: During the conditional test, it is not allowed to take the test sample out of the test box for measurement before recovery and put it back into the test box again. If you need to understand the performance of the test sample at a specific time before the end of the duration, For each specific time, an additional batch of test samples shall be added, recovery and final measurement shall be carried out separately for each batch of test samples).

Attachment: Recovery after the test

The test samples should be restored under standard atmospheric conditions until thawing. In order to remove water droplets, the test samples can be shaken by hand, or air blown at room temperature for a short time. When the test samples are restored under standard atmospheric conditions, the recovery time should be sufficient to reach The temperature is stable, the least is 1h. When a few samples are tested, and the recovery time of 1h is sufficient, the longest recovery time is 2h. All measurements must be completed at the end of this time. If relevant specifications are required During the recovery period, the test sample must be energized or loaded, and its performance should be continuously measured. When the standard atmospheric conditions are not suitable for the test sample, the relevant specifications may specify other recovery conditions. It is required to conduct visual inspection and test of electrical and mechanical properties on test samples.

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