The Research Of The Cable Fault Location In Intelligent System

With the development of our country's economy, the high and low voltage wires of city,countryside, factory, mine and construction of national prevention are replaced gradually bycable. People's living and producing cann't go smoothly without electric energy. Then theeffectness of cable fault on the socity is increasing, and it has significant impotance to ensurethe safety of cable operation. After the extensive investigation of the development of national and internationalintelligent measuring system and the real situation of cable fault, the drawback of electricbrige method for cable fault location is analyzed. According to a new theory of electric brigemethod and combining with USB tecgnology, an intelligent instrument of cable fault locationis developed, and the software used in the upper computer for test the cable fault point hasbeen programmed. The intelligent cable fault location instrument is an organical combination ofmicrocomputer and instrument. It is mainly made of a single chip computer AT89C52 and aperipheral embeded USB interface. Ultimately, it is a computer system. The intelligent cablefault location instrument has many peculiarity by testing fault cable in laboratory ,for examplethe measure range is 0 ～ 60kM, the relative error is smaller than 0.5%. In-systemProgramming logic device which will be useful in debuging the circuit board is used.Measurement date can be displayed by the LDE showing, and it has the USB port supporting"Plug and Play" with electricity, the highest rate is 12Mb/s. Bsides reading measurement date from the intelligent cable fault location instrumentthrough USB port, processing measurement date and putting the past date into thedocument,the processing software for PC can edit date including deletion, modifying, copying,pasting locating, substitution and so on, and finally it can print data in report in order tosummarize and consult. The intelligent cable fault location instrument overcomes the shortcoming of singlefunction and no storing past date. It uses USB interface with the function of "Plug and Play"to connect the intelligent cable fault location instrument with PC, in order that it can work as asystem. Moreover, In-system Programming logic device which is used in the final debuggingplays an important role.