The constant temperature and humidity test chamber is a test chamber that integrates high temperature, low temperature, and humid heat - the high and low temperature humid heat alternating test chamber. Its repair difficulty is greater than other environmental testing equipment, and it is representative. Taking the high and low temperature damp heat alternating test chamber as an example, let's talk about the structure of the constant temperature and humidity test chamber, as well as some common faults and troubleshooting methods.

1、 Construction of Constant Temperature and Humidity Test Chamber

The constant temperature and humidity test chamber consists of a box body, an air circulation system, a refrigeration system, a heating system, and a humidity control system. The wind circulation system generally adopts a structure with adjustable air supply direction;There are two types of humidification systems: boiler humidification and surface evaporation;The cooling and dehumidification system adopts an air conditioning cooling structure;The heating system adopts two structures: electric heating fin heating and direct heating with electric furnace wire;The temperature and humidity testing method adopts the dry wet bulb testing method, and there is also a direct measurement method using humidity sensors;The control and display interface adopts independent temperature and humidity separation and temperature and humidity combination controllers.

2、 Some common faults and troubleshooting methods of constant temperature and humidity test chamber

In high-temperature testing, if the temperature change does not reach the test temperature value, the electrical system can be checked and the faults can be eliminated one by one. If the temperature rises slowly, you need to check the air circulation system to see if the regulating baffle of the air circulation is open normally. Otherwise, check if the motor of the air circulation is running normally. If the temperature overshoot is severe, then it needs to be adjustedPIDSet the parameters. If the temperature rises directly and is protected against overheating, the controller will malfunction and the control instrument must be replaced.

If the low temperature does not meet the test criteria, then you need to observe the temperature changes, whether the temperature drops slowly or there is a trend of temperature recovery after reaching a certain value. The former should be checked to see if the working chamber is dried before conducting the low temperature test. After keeping the working chamber dry, the test samples should be placed in the working chamber before conducting the test. If too many test samples are placed in the working chamber, causing the air in the working chamber to not circulate sufficiently, after ruling out the above reasons, you need to consider whether it is a fault in the refrigeration system. In this case, the rotor pump needs to be repaired by professional personnel from the manufacturer. The latter phenomenon is caused by poor usage environment of the equipment, such as the ambient temperature and placement of the equipment(The distance between the box and the wall behind it)To meet the requirements(There are regulations in the device operation and usage instructions).

When the equipment suddenly malfunctions during the test operation, corresponding fault display prompts and audible alarm prompts will appear on the control instrument. The operator can quickly identify which type of fault it belongs to by referring to the troubleshooting chapter in the operation and use of the equipment, and then ask professional personnel to quickly troubleshoot it to ensure the normal progress of the experiment. Other environmental testing equipment may experience other phenomena during use, so it is necessary to analyze and eliminate them specifically.

The constant temperature and humidity test chamber should also be regularly maintained, the condenser of the refrigeration system should be cleaned regularly, the moving parts should be lubricated according to the instructions, and the electrical control system should be regularly maintained and inspected. These tasks are essential.