Both two-box and three-box thermal shock chambers are designed to test how well a product can withstand rapid temperature changes. The main differences lie in test method, structure, and application scenarios:
Two-box Thermal Shock Chamber
Test Process: Uses a moving basket that transfers the sample between a hot zone and a cold zone.
Speed: Faster temperature transition (shorter switching time).
Structure: More compact; suitable for smaller sample sizes.
Pros: Quick response, space-saving, can be used independently as high or low temp chamber.
Considerations: Product is physically moved during the test, which may not suit fragile or wired samples.
Three-box Thermal Shock Chamber
Test Process: The sample stays fixed in one test area, while hot and cold air are alternately blown in.
Stability: No physical movement of the product — ideal for fragile items or when connecting to electrical monitoring systems.
Structure: Larger footprint, includes a room temperature stage.
Pros: No vibration or movement; better for electrical or sensitive devices.
Considerations: Slightly slower switching time and higher cost due to more complex design.
Which one should I choose?
If you need rapid testing with compact design, choose the two-box type.
If your product is fragile, sensitive, or requires stable monitoring during testing, the three-box chamber is recommended.