The constant temperature and humidity test chamber, also known as constant temperature and humidity test machine, programmable heat and humidity test chamber, is used to test heat resistance, cold resistance, dry resistance, moisture resistance of materials under a variety of climate conditions.
A constant temperature and humidity chamber is applicable to carry out adaptability tests of instruments, electricians, electronics, parts, and materials when they are stored, transported, and used in the climate condition with high humidity and temperature or low humidity and temperature. It is used to test several raw materials, including electronics, electrical, and plastics, for resistance to heat, cold, dryness, and moisture. Meanwhile, it is a reliable testing equipment for quality control engineering.
Selection principles of the constant temperature and humidity chamber
Constant temperature and humidity chamber must accurately or similarly simulate the process of the use, storage, shipping, and other aspects of engineering products. Additionally, it must satisfy the demands of the uniformity of the temperature field and the accuracy of the temperature control in accordance with defined test specifications, requirements of test value for high temperature and low temperature and the time of test which are specified by various types of products. We can guarantee a precise reproduction of environmental conditions in the environmental test only by doing this.
Environmental test equipment may carry out multiple tests of the same type of product while an engineering product under test may be put into different environmental test equipment for testing. The environmental conditions created by the environmental test equipment are required to be repeatable in order to ensure the test results are comparable which are all about the same product in the same test specification under the specified environmental test conditions.
Measurability and controllability
The environmental conditions provided by any environmental condition must be observable and controllable, which is not only set to limit environmental parameters to a certain tolerance range, but also for the safety of the experiment in order to eliminate the unnecessary loss caused by the uncontrolled environmental condition.
For every environmental or reliability test, there are some strict regulations on the category of environmental factors, value, and tolerance. Moreover, environmental factors which are not needed in the test should be prevented from the test for providing the exact evidence to analyze the product failure and failure mode. As a result, the test product is only allowed to be put in the specified environment instead of any other environmental stress interference.
Safety and reliability
The test cycle of environmental testing, especially reliability testing, is long. Sometimes, the machine will test military products with a very high value. In the test process, the testers need to carry out the operation or test around the scene. Therefore, the environmental test equipment is required to be characterized by safe and easy operation, reliable use as well as long working life, and so on for the normal operation of the experiment.
Installation of constant temperature and humidity chamber
Here are some regulations for the place where the constant temperature and humidity chamber is installed to facilitate the heat dissipation and maintenance of the box.
- There should be 300mm between it and the nearby wall or object.
- We should identify a location where the average annual temperature ranges from 15 to 35 °C and the relative humidity is larger than 85%.
- There should not be a sharp change in the ambient temperature of the installation place.
- It should be mounted on a smooth surface (when installing, we should confirm that it is placed horizontally by using the level).
- It ought to be set up in an area with minimum dust, good ventilation, freedom from combustible or explosive items, high-temperature heat sources, or without direct sunshine.
- As much as possible, it should be installed close to the power source.
The maintenance of constant temperature and humidity chamber
The constant temperature and humidity chamber will be more prone to damage if it is not properly maintained. Instead, the machine can be distinguished by longer life and convenient operation owing to scientific maintenance. Additionally, the individual using the machine needs to know how it works and be able to solve simple issues. The following are the maintenance of constant temperature and humidity chambers in daily life.
The condenser, humidifier, humidification water tray, and inner box should all be inspected for cleanliness.
Additionally, the test cotton should be examined for stains and hardening.
Next, we must figure out whether the constant temperature and humidity test chamber’s safety device works normally.
Furthermore, testing hazardous things like explosives, combustibles, and flammable materials are not permitted.