As commonly used environmental simulation equipment, high and low temperature test chambers and constant temperature and humidity chambers can simulate different temperature and humidity conditions, helping to test the performance and reliability of products in corresponding environments. However, how should we choose between these two devices? Below, we will delve into the differences between the two from dimensions such as functionality, structure, and application scenarios.

1、 Functional differences

The high and low temperature test chamber, as the name suggests, is mainly used to simulate high and low temperature environments and test the performance and reliability of products under simple temperature changes. Its temperature range is usually very wide, commonly ranging from -70 ℃ to 150 ℃, and some special customized models have a wider temperature range. In the electronics industry, it is possible to test whether electronic components experience performance degradation when working at high temperatures, or whether they can start normally in low-temperature environments; In the automotive industry, high temperature exposure and low temperature cold start tests can be conducted on components such as car engines and sensors to verify their working stability in high and low temperature environments.

The constant temperature and humidity chamber has more comprehensive functions. In addition to precise temperature control, it can also accurately control humidity and simulate complex and variable temperature and humidity combination environments. The temperature range is generally from -20 ℃ to 85 ℃, and the humidity range is mostly from 20% to 98% RH. In the process of drug development, it is necessary to strictly control the stability of drugs under specific temperature and humidity conditions, and constant temperature and humidity chambers are used; In the food industry, it is possible to simulate temperature and humidity conditions in different seasons and regions, test the shelf life and spoilage of food, and provide data support for food storage and transportation.

2、 Structural differences

The structure of the high and low temperature test chamber is relatively simple, mainly composed of a refrigeration system, a heating system, and a circulating air system. The refrigeration system is responsible for cooling, the heating system achieves heating, and the circulating air system promotes air circulation inside the box to ensure even temperature distribution. Taking the common air-cooled high and low temperature test chamber as an example, the compressor, condenser, evaporator and other refrigeration components work together to transfer heat through the change of refrigerant state; Heating elements such as heating wires are energized to generate heat and increase the temperature inside the box; The fan drives air flow to avoid temperature stratification.

The constant temperature and humidity chamber is based on the high and low temperature test chamber, and is equipped with a humidification system and a dehumidification system, making the structure more complex. Humidification systems often use methods such as steam humidification and ultrasonic humidification to convert water into steam, which is injected into the box to increase humidity; The dehumidification system uses technologies such as condensation dehumidification and rotary dehumidification to remove excess moisture inside the box and maintain stable humidity. At the same time, in order to accurately control temperature and humidity, the constant temperature and humidity chamber is equipped with more precise sensors and control systems to monitor and adjust the environmental parameters inside the chamber in real time.

3、 Differences in application scenarios

High and low temperature test chamber in the field of electronic appliances: widely used for high and low temperature performance testing of electronic components, circuit boards, and whole machine products, ensuring the reliability and stability of products in different temperature environments. Computer CPUs, mobile phone batteries, etc. all need to be tested in high and low temperature test chambers. Materials Science Research: Helps to study the thermal expansion characteristics, toughness, hardness and other property changes of new materials in high and low temperature environments, providing key data for material research and improvement, and accelerating the development process of new materials. Automotive manufacturing industry: Conduct high and low temperature tolerance tests on key components such as automobile engines, transmissions, body materials, and various electronic devices to ensure safe and stable operation of automobiles under different global climate conditions.

In the biopharmaceutical industry, constant temperature and humidity chambers are used to simulate different temperature and humidity conditions during drug research and development, production, and storage processes. They are used to conduct drug stability and acceleration tests, determine drug expiration dates, storage conditions, and ensure drug quality and safety. Food and beverage industry: Simulate the temperature and humidity environment that food may encounter during processing, storage, and transportation, test the physical and chemical properties of food, such as the shelf life of bread, the melting temperature of chocolate, and the precipitation of beverages, optimize food packaging and preservation technology. Electronic precision manufacturing: For high-precision electronic products such as chips, sensors, optical instruments, etc., humidity has a significant impact on their performance and lifespan. The constant temperature and humidity chamber provides a stable temperature and humidity environment, meets production and testing needs, and reduces product defect rates.

4、 Cost difference

The procurement cost of high and low temperature test chambers is usually affordable due to their relatively simple functions and structures. The constant temperature and humidity chamber, due to its complex humidity control function and higher requirements for temperature and humidity control accuracy, has a more precise and complex equipment structure and control system. The procurement cost is often 30% -50% higher than that of the high and low temperature test chamber, or even more, depending on factors such as equipment specifications, brands, and performance parameters.

In terms of operating costs and energy consumption: During the operation of the high and low temperature test chamber, the main energy consumption is used for temperature regulation, with relatively low energy consumption. The constant temperature and humidity chamber not only needs to control the temperature, but also consumes a large amount of energy during the humidification and dehumidification processes. The operating energy consumption is 50% -100% higher than that of the high and low temperature test chamber.

Maintenance: Due to its complex structure and numerous components, the constant temperature and humidity chamber has a relatively high probability of failure, resulting in increased maintenance costs. For example, the humidification bucket of the humidification system, the wheel of the dehumidification system, and other components need to be cleaned and replaced regularly; Precision sensors and control systems also require professional calibration and maintenance to ensure the accuracy of temperature and humidity control.

5、 Differences in accuracy and stability

The high and low temperature test chambers have high requirements for temperature control accuracy and stability. The common temperature control accuracy can reach ± 0.5 ℃, and some equipment can even reach ± 0.1 ℃. Throughout the entire testing process, the temperature can be consistently maintained near the set value, providing a precise temperature testing environment for the product and meeting the testing needs of various temperature sensitive products.

The constant temperature and humidity chamber needs to balance high-precision control and stability of temperature and humidity. The temperature control accuracy is generally within ± 0.5 ℃ - ± 1 ℃, and the humidity control accuracy can reach within ± 3% RH. To achieve this goal, the constant temperature and humidity chamber adopts more advanced control algorithms, high-precision sensors, and high-quality execution components to ensure the accuracy and reliability of the testing environment, providing stable and accurate environmental protection for product testing that is extremely sensitive to temperature and humidity.

6、 Selection suggestions

According to the testing requirements, if only the performance of the product in simple high or low temperature environments, such as high-temperature aging testing of electronic components, low-temperature storage testing, etc., the high and low temperature test chamber can meet the needs. If product testing has strict requirements for humidity, such as drug stability testing, precision electronic instrument moisture-proof testing, etc., a constant temperature and humidity chamber must be selected to simulate real complex environments.

Considering budget factors, if the budget is limited and there is no need for humidity testing in the short term, high and low temperature test chambers can be selected. If the budget is sufficient or humidity related testing may be involved in the future, in the long run, choosing a constant temperature and humidity chamber in one step is more cost-effective and avoids repeated equipment purchases in the later stage.