Study Of Domestic Air Conditioner Fault Diagnosing System Based On Microprocessor

Because of the insufficient reliability of nowadays air conditioner fault diagnosing system (ACFDS), the writer of the thesis has concluded domestic air conditioner fault diagnosing logic based on 5 operating temperature and the analysis of influence relevant to conditioner characteristic and the link between fault and characteristic. Based on which and the following work, the ACFDS has been designed, and the reliability of which has been improved.1,Has obtained conditioner fault characteristic and fault diagnosing logic.With the reference to conditioner fault table and experiment, the writer adjusts different assigned faults and has obtains the relationship between the fault and operating temperature.Based on the relationship and comparison between analysed characteristic and normal ones, the writer has established fault diagnosing logic and provided fundamentals to the ACFDS.2,Accomplished the design of the ACFDS.Has studied and finished ACFDS based on AT89C52 microprocessor which is composed of the following hardware and software.To obtain the circumstance and operating temperature, a temperature measurement circuit has been applied, and the voltage signal transformed from temperature signal is read by microprocessor directly from temperature table. The serially controlled VLCM128*64 LED is serially controlled by microprocessor and displays relevant content.With the relationship based on reference and experiment between the operating time and varies faults, the compressor operating time is calculated by software and a timer circuit which is independent on AT89C52 microprocessor.To judge the operating state of conditioner, relays have been connected with main switches of air conditioner and the operating signal delivered from the coupled circuit is transferred to the interrupt port of microprocessor.The hardware has a connection between maintenance operating button and the...