The Development Of Digital Test Device For Relay Protections

By using application program the Virtual Instrument combines the general computer with the functional module, thus the user can make use of PC powerful graphic environment to realize the control of the instrument and the analysis, storage and displaying of the data, it changes the traditional use method and improves the efficiency of the instrument. The paper discusses the application of the Virtual Instrument technology on the relay protection testing, and use the USB (Universal Serial Bus) as the communication interface between the host machine and testing device.