MCB and MCCB are the short forms of Miniature Circuit Breaker and Molded Case Circuit Breaker. As contained in their names, they are both circuit breaker, meaning, they are electrical switches capable of opening and closing an electrical circuit in all operating conditions, including fault situations.
The first difference between the two circuit breakers is their capacity. MCB (Miniature Circuit Breaker) comes with the capacity of 100amps, while MCCB comes with the capacity of 2500amps. Due to the lower capacity of MCB, it is used for connection with low-energy. It is used for home wiring and other smaller electronic works. MCCB, on the other hand, is used for the electrical connection of high power equipment.
The interrupting rating of MCB is quite different from the interrupting rating of MCCB. MCB comes with the interrupting rating of 18,000, while MCCB comes with the interrupting rating of 200,000. Finally, the position of both MCB and MCCB must be known for safety reasons.