Beijing high and low temperature test chamber is common in environmental test equipment Temperature test equipment, similar related products with high and low temperature alternating test chambers, constant temperature and humidity test chambers, high and low temperature and humidity transformation test chamber, etc. The above test equipment has no extractional temperature, and the control method is very similar, and below will follow us to learn more about the temperature control of the high and low temperature test chamber products.
Beijing high and low temperature How to achieve high temperature and low temperature?
Talking about the temperature, there is High temperature and low temperature. High temperature control is a heating process and is more simple. Heating of the high and low temperature test chamber with independent heating mode, far-infrared nickel-chromium alloy high-speed heating electric wire, temperature control adopts p middot; I middot; D + S Midd 2; S Midd 2; R system coordinated control, output power is calculated by microcomputer, With high precision and high efficiency. In order to achieve a fast temperature rise rate and high temperature, it is generally generally controlled by increasing the number of heated electric wire and improving the control of temperature control software. The refrigeration system of the high and low temperature test chamber adopts the unit Fluon refrigeration system composed of Fully closed compressors. The refrigeration work is based on the inverse card, which is cyclically composed of two isothermal processes and two heat insulating processes. The refrigerant is compressed to a higher pressure through the compressor, which consumes the exhaust temperature to increase the refrigerant to heat the heat to the four-week medium. This cycle is beginning to reach the purpose of cooling. The high and low temperature test chamber adopts a balanced temperature (BTC), which is both in the case of a refrigeration system in the case of continuous operation, and the control system controls the output of the heater according to the set temperature point, and finally reaches one. dynamic equilibrium.
High and low temperature test box low temperature retention unconception analysis: first observe the high low temperature box refrigeration compressor Whether the high and low temperature test chamber can be activated, if the compressor of the high and low temperature box can be activated during the operation, it means that the electrical line from the main power supply to each high and low temperature box compressor can be normal, and there is no problem in the electrical system. .
When there is no problem with the electrical system of the high and low temperature box, the refrigeration system is continued. First check the two sets of refrigeration compressor of the high and low temperature box. If the exhaust gas of the low temperature-free compressor is lower than the normal value, and the inhalation pressure is evacuated, this means that the refrigerant of the main refrigeration unit is obvious. . Then use the hand to touch the exhaust and suction line of the host group R23 compressor, if the temperature of the exhaust line is not high, the temperature of the suction line is not low (unruly), this It also illustrates the lack of R23 refrigerant of the host group.
High and low temperature test one is a host group, and the other is a secondary unit, at cooling rate At the same time, the two sets of units work at the same time, and the two sets of units work at the same time during the temperature maintenance phase. The temperature is initially stabilized, and the auxiliary unit stops working, and the main unit is maintained to maintain temperature cooling and stability. If the host group R23 leaks, the cooling effect of the host group will not be high. Due to the cooling process, the two units work at the same time, so there is no temperature and stable phenomenon, but indicates that the cooling rate is lowered. In the temperature maintenance stage, once the auxiliary unit stops working, the host group has no refrigeration, and the air temperature in the high and low temperature test chamber will rise slowly. When the temperature rises to a certain extent, the control system will start the auxiliary unit to cool down, then The auxiliary unit stopped working, so repeatedly, the low temperature remained fault phenomenon.
For the above analysis, the fault phenomenon of high and low temperature test box low temperature remains, analysis and judgment is basically From easy to difficult, first outside, the principle and work of familiarity and understanding of high and low temperature test chambers are familiar with the principle and work of high-low temperature test chambers.