There are different ways to improve the short circuit breaking ability of MCB products at different stages.According to our experience, the selection of suitable thermoplastic material can shorten the cooling time before arc and improve the efficiency of circuit breaker, so as to improve the performance of circuit breaker.This is because the arc generated at the time of breaking is accompanied by high temperature. Under the high temperature environment, thermoplastic materials will experience thermal weightlessness and release gas, which is helpful to improve the efficiency of arc extinguishing.