Leakage Protection Device Operating Characteristics Microcomputer Testing Instrument

It is one of effective measures to prevent electric shock by equiping residual current operated protective devices(RCD) in the low-voltage electric power systems, it is also a technique measure to avoid fire accident and damages to electricity equipments caused by leakage current. The distinguishing amplitude and phase RCD have applied extensively in the reform of our countryside electric power systems. On the basic of plenty market investigation and according to the lack of well-made testing instrument for distinguishing amplitude and phase RCD, the dissertation develops the instrument with 80C196KC single-trip microcomputer combined engineering application.In addition to test residual operating current , residual non-operating current and break time,the instrument can also test the non-operating phase. It provides measures to test the RCD quantity for the enterprise which manufactures RCD and the branches which use RCD, so it has positive meanings to the safety of our countryside electric power systems.The dissertation puts forward the method that gengerates sine alternating signa(?) with DDS . Adopting single-trip microcomputer and D/A converter, it presents a scheme to gengerate alternating current whose amplitude and phase are adjustable continuously. Based on Intel 80C196KC ,adopting high property assistant circuits and proper measures to enhances the resistance of disturbance ability , the dissertation designs the testing instrument for work characteristic of RCD which can be useed in strong magnetic field. The function of the instrument is full-scale,including the basic testing item of RCD.Several output pattern,such as LCD,printer and PC,etc.can meet the demand of testing in site. The menu adopts large full Chinese character display, has humanized interface,and it is easy to operate. The result tested in laboratory and site comes to the anticipant request,it proves that the instrument works steadily,measures exactly,and has reliable property.Settling bobtail experiment, the dissertation presents the scheme about reliability of RCD composed of the success rate and the failure rate . The RCD belongs to the protector that operate non-countinually.The reliability of RCD mainly check on its work characteristic and the mode of the failure.The dissertation gives out the estimate method of dependable characteristic measures, adopting the success rate R and the...