Motor protection using SEL-710 microprocessor relay

This paper provides details about testing a microprocessor based relays. The Relay used for testing is a microprocessor based multifunction motor protection Relay (SEL-71 0). This paper explains tests that are carried on the relay when different fault occurs on a motor. Chapter 1 explains various protection devices used in power system Chapter 2 deals with basic functionality of microprocessor based relay and Chapter 3 deals with the circuit required for testing the relay. Response of the relay is indicated by respective LED' s. The ON I OFF status of the LED indicate the fault in the line. If a fault exits in the line, the relay sends a signal to the circuit breaker which opens the line and clears the fault. The line is then restored upon clearance of fault