Microprocessor based integrated feeder protection RIR 2000

The authors present a microprocessor based integrated feeder protection with an autoreclosing function added to the protection scheme. The relay´s design is based on 16-bit microprocessor with the corresponding 1/0 units for measuring analog and digital quantities. The digital processing of measured currents enables a separate setting of operating values, selection of all types of inverse or constant time characteristics for individual phases and earth fault. The microprocessor design enables automatic relay calibration, software and hardware self testing, and communication with the substation computer