Author(s)

Qunsheng Liu, Lin Wang And Huarui Cheng

Corresponding Author

Qunsheng Liu

ABSTRACT

Although significant progress has been made about fault detection and diagnosis (FDD) in the field of refrigeration and air conditioning, the faults that can be effectively diagnosed are still very limited. The routine maintenance and troubleshooting of refrigeration system are normally fulfilled by professional refrigeration technicians or engineers. A small-scale refrigeration system experimental device is designed and developed, as a powerful tool for teaching general theories and training practical skills for the novices of refrigeration system, This device can measure and display temperature and pressure in typical positions of a refrigeration system. In addition, it can generate real common faults for the purpose of experiments and practical training, including filth blockage, excessively high pressure, excessively low pressure, refrigerant undercharge and refrigerant overcharge. With the switching function between normal operation mode and fault operation mode, this device has been successfully applied to the college curriculums of PLC programming, refrigerating equipment maintenance and repair, etc. It is showed that the device facilitates the novices of refrigeration system to understand the changes of temperature and pressure in typical positions of a normal refrigeration system, the reasons of common faults, the methods of fault diagnosis and troubleshooting.

KEYWORDS

Refrigeration system, fault simulation, real faults, filth blockage, excessively high pressure, excessively low pressure, refrigerant undercharge, refrigerant overcharge