By repeatedly changing the temperature and humidity, this testing service evaluates reliability and durability of the changes. We perform temperature and humidity cycle test (heat cycle test) using temperature and humidity chamber. The chamber adjusts the temperature and humidity, to perform environmental and reliability tests under various temperature and humidity environments. Customized tests, and tests with powered-up and operating are also available.

In thermal shock test, UL evaluates products’ resistance to sudden change of temperature, by exposing products to high temperature and low temperature alternately in a short time. It is also known as thermal cycle testing. Repeated rapid temperature changes cause the test material to expand and contract. Materials with different coefficients of expansion produce stresses due to differences in the rate of expansion, which can cause cracks and fractures when such is repeated. In addition to damper type thermal equipment, this service features an elevator type thermal shock equipment that is used for testing for Europe with high capacity and is faster to reach the set temperature, allowing us to support more demanding environmental tests.

UL simulates the thermal shock caused by cold water splashing when a vehicle travels on a wet road in winter. For electronic systems and components installed exterior of automotive, we test the impact of thermal shock on both products’ mechanical strength and waterproof performance. In this service, we provide splash water test that apply cold water from 0 to 4 degrees Celsius to the product, and submersion tests that submerge the product in cold water while keeping in operation. We are also able to customize water temperature, depth of water, and liquid type.

For electrical and electronic products, we evaluate water resistance and waterproofing when subjected to outdoor wind, rain, and water splashing, etc. For automotive components, we provide testing service to evaluate waterproofing, water resistance, drainage, and changes in functionality. This service enables water-resistant testing corresponding to IP code. UL is also able to support cycle tests using a thermostatic bath and tests during power-up and while in operation.

HAST試験は内圧を上げる為に温度を上昇させ、水蒸気を発生させると同時に槽内の空気を排気弁から排出し圧力を低下させる試験です。槽内に空気がなくなることで、試験環境と実環境に差異が生まれますが、槽内に空気を残留させる機能があり、空気中の酸素が要因である試験表面酸化などの劣化を再現できます。加速寿命試験時にプリント基板で必須となるイオンマイグレーションの評価も可能です。