In any electrical system, protection is the most important requirement to secure both human lives and application from the damage. The THREE PHASE EARTH LEAKAGE CIRCUIT BREAKER (ELCB) is a design which could be implemented in three phase electrical environment to provide protection to user as well as equipments against any earth leakage fault. In three phase circuit all current carrying conductors must be sensed. An Earth-leakage circuit breaker (ELCB ) is a safety device used in electrical installations with high Earth impedance to prevent shock. It detects small stray voltages on the metal enclosures of electrical equipment, and interrupts the circuit if a dangerous voltage is detected. Once widely used, more recent installations instead use residual current circuit breakers which instead detect leakage current directly.