Mcb= miniature circuit breaker pahle 1a ampere to 63a tak ata tha ,abhi ke time 1 ampere to 125 tak ata hai mcb used for low ampere for short circuit over load protection house, residential,commercial. mccb= moulded case circuit breaker 80a to 125 to 1000 ampere tak ata hai mccb used for high ampere for short circuit over load protection, commercial and industrial, dono ek hi kam hai short circuit over load protection fark yahi hai low ampere and high ampere maan ke chaliye mcb ka bada bhai hai mccb.😇😇😇😇😊😉