Which type of system is usually required for ultra-low temperature applications?

For ultra-low temperature applications, a cascade system is typically required due to its ability to achieve much lower temperatures than standard refrigeration systems can. In a cascade system, two or more refrigeration cycles are used in tandem. The first stage cools a refrigerant to an intermediate temperature, and then the second stage cools the refrigerant to ultra-low temperatures. This design allows for efficient temperature control and improved performance in reaching and maintaining extremely low temperatures, which is essential in applications such as cryogenics, research laboratories, and specific industrial processes.

Other systems, like coolers and comfort cooling systems, primarily serve higher temperature ranges and are not designed for extreme conditions. Standard freezers might reach low temperatures, but they generally cannot achieve the ultra-low temperatures that a cascade system is capable of, making the cascade system the preferred choice for these specialized applications.