Examples of Climatic Simulation Tests:
a) Storage Environment Simulation
Products are sustained to different storage/ warehouse conditions in the manufacturing processes including:
Production→ warehousing→ delivery (transportation) → (distribution center – warehouse) → sales foothold (warehouse) → end users. This means products are subject to environmental factors of high- or low-temperature, humidity, salty air (sea freight), etc.
IEC recommends that storage environment shall be simulated at least with tests of low-temperature storing, dry and high-temperature storing and humidity stability, to verify that the product or packing will not suffer from the storage environment.
b) Temperature and Humidity Simulation
The temperature and humidity condition variations change as the geographical locations and the climatical settings change.
According to IEC60721, there are four conditions: High Temp./Low Humidity, High Temp./High Humidity, Low Temp./High Humidity, and Low Temp./Low Humidity. In IEC60721 and ETSI 300 019, there is a clear chart on recommended temperature and humidity.
To avoid confusion and obscurity of the true reason for failure, international company will conduct dry heat test, cold test, constant temperature/humidity test, humidity cycle test separately.
For plastic, PCB, PCBA multi-hole materials or products, each material will have a different effect to temperature and humidity. Temperature effects are usually plastic deformation, product overheat, poor cold start, etc. For multi-hole material and products, the breathing effect in a humid environment will cause surface moisture absorption, permeation, and condensation; in a low temperature environment, accumulation of static will cause failure. Therefore, different temperature and humidity will cause different failure modes.
Only outdoor products are obligated to conduct condensation test. Due to the fact that condensation can easily cause shorts and fail, indoor products are often prevented from condensation during humidity testing.
Often humidity effects include loss of physical strength, chemical change, deterioration of insulation, short circuit, oxidation on metal surface, loss of flexibility, accelerated chemical change, component deterioration, etc.