Air Circuit Breaker (ACB) is an electrical protection device used for short circuit and overcurrent protection up to 15kV with amperes rating of 800A to 10kA. It operates in air (where air-blast as an arc quenching medium) at atmospheric pressure to protect the connected electric circuits. ACB has completely replaced by oil circuit breaker because it is still a preferable choice to use an ACB because, there is no chance of oil fire like in oil circuit breaker.