GB 2951.14-2008 "General Test Methods for Insulation and Sheath Materials of Electric and Optic

The purpose of low-temperature testing is to determine the adaptability of military and civilian equipment to storage and operation under low-temperature conditions. At present, there are laboratories that can conduct low-temperature tests, such as the Environmental Reliability and Electromagnetic Compatibility Testing Center and the Aerospace Environmental Reliability Testing and Testing Center. Purpose of the experiment: Used for scientific research, preservation of medical supplies, low-temperature experiments and storage of special materials such as biological products, ocean products, electronic components, chemical materials, etc. Low temperature testing is used to assess the adaptability of products to storage and use under low temperature environmental conditions. It is commonly used for type testing of products during the development stage and screening testing of components. The technical indicators for low-temperature testing include temperature, time, and rate of rise. Note that when the product is taken out of the low-temperature box, condensation water may occur due to sudden temperature changes. (Applicable to temperature cycling, temperature shock, and damp heat tests) The sample is placed in the test chamber to maintain the uniformity of the surface temperature of the sample. The distance between the sample and the box wall is at least 5cm. GB/T 2423.1 Low temperature test methods include: temperature gradient of heat dissipation samples, and temperature gradient of non heat dissipation samples. After the test is completed, the sample needs to be restored to a stable state inside the box, or placed in a normal temperature and humidity environment to restore to a stable state, Under specific circumstances, it is required to thaw the sample by blowing slightly hot air before heating it up to a stable state