Correct maintenance of high and low temperature damp heat test chamber method

There are many kinds of environmental test equipment, but the most widely used environmental test equipment is high temperature, low temperature and damp heat test chamber. Nowadays, it is popular as a test box that combines high temperature, low temperature and damp heat. High and low temperature damp heat test chamber, its repair The difficulty is larger and more representative than other environmental testing equipment. Let's take the high and low temperature damp heat test chamber as an example. Let's talk about the structure of the high and low temperature damp heat test chamber and some common faults and troubleshooting methods.

(I) Construction of common high and low temperature damp heat test chambers In addition to correct operation according to the operating procedures, test personnel should also have an understanding of their structure. The high and low temperature damp heat test chamber is composed of a box body, a wind circulation system, a refrigeration system, a heating system and a humidity control system. The air circulation system generally adopts a structure that can adjust the direction of air supply; the humidification system has two types of boiler humidification and surface evaporation; the cooling and dehumidification system adopts an air conditioning working condition refrigeration structure; the heating system adopts electric heating fin heating and electric furnace direct heating. Two kinds of structures; the temperature and humidity test method adopts the dry and wet ball test method, and also the direct measurement method of the humidity sensor; the control and display operation interface adopts the method of separate temperature and humidity separation and temperature and humidity combined controller.

(2) Some common faults and troubleshooting methods for high and low temperature damp heat test chambers:
1. In the high temperature test, if the temperature change does not reach the test temperature value, the electrical system can be inspected and the faults can be eliminated one by one. If the temperature rises very slowly, it is necessary to check the air circulation system to see if the regulating baffle of the wind cycle is normal. On the contrary, check whether the motor of the wind cycle is running normally. If the temperature is too high, you need to set the PID setting parameters. If the temperature rises directly and the temperature is over-protected, the controller will fail and the control instrument must be replaced.
2. If the low temperature does not reach the test index, then you should observe the change of temperature, whether the temperature drops very slowly, or the temperature rises after the temperature reaches a certain value. The former should check whether it will be before the low temperature test. Dry the studio, keep the studio dry, and then put the test sample into the work room and then test it. If the test sample in the high and low temperature damp heat test chamber is too much, the wind in the work chamber cannot be fully circulated. After the above reasons, it is necessary to consider whether it is a fault in the refrigeration system, so it is necessary to ask the professional of the manufacturer for maintenance. The latter phenomenon is caused by the poor use of the equipment. The ambient temperature at which the equipment is placed and the location where it is placed (the distance between the rear of the cabinet and the wall) must meet the requirements (as specified in the operating instructions for the equipment).
3. In the high-low temperature damp heat test chamber, the actual humidity will reach 100% or the actual humidity will be very different from the target humidity. The value is much lower. The former phenomenon may be caused by the drying of the gauze on the wet bulb sensor. It is necessary to check whether there is water shortage in the water tank of the wet bulb sensor. The water level in the water tank is automatically controlled by a water level controller. Check whether the water supply system of the water level controller is normal and the water level controller works normally. Another possibility is that the wet gauze is hardened due to the long use time or the purity of the water supply, so that the gauze becomes hard and the gauze can not absorb moisture and is dry. The above phenomenon can be eliminated by replacing or cleaning the gauze. The latter phenomenon is mainly because the humidification system does not work. Check the water supply system of the humidification system, whether there is a certain amount of water in the water supply system, whether the water level control of the humidification boiler water level is normal, and whether the water level in the humidification boiler is normal. High and low temperature damp heat test chamber If everything above is normal, then check the electrical control system, which should be repaired by professional maintenance personnel.
4. When the high and low temperature damp heat test chamber suddenly fails during the test operation, the corresponding fault display prompt appears on the control instrument and an audible alarm prompt is displayed. The operator can quickly check which type of fault is involved in the troubleshooting chapter of the operation of the equipment, and then ask the professional to quickly eliminate the fault to ensure the normal operation of the test. Other environmental testing equipment will have other phenomena in use, and it will be specific phenomena, specific analysis and elimination.
The high-low temperature damp heat 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, the electrical control system should be regularly maintained and checked, etc. These tasks are indispensable.