Power System Protection S.A.Soman Principles of Overcurrent Protection Limitations of a Fuse Algorithm for Overcurrent Relay Time Multiplier Setting Classification of Overcurrent Relay Lack of Coordination Problem IEC Standard Equations IEEE Standard Equations Pick up Current Setting Guidelines Primary and Back up Relays Setting and Coordination Summary Power System Protection S.A.Soman Department of Electrical Engineering IIT Bombay Fundamentals of Overcurrent Protection